< draft-ietf-manet-dlep-04.txt		draft-ietf-manet-dlep-05.txt >
	Mobile Ad hoc Networks Working S. Ratliff		Mobile Ad hoc Networks Working S. Ratliff
	Group B. Berry		Group B. Berry
	Internet-Draft G. Harrison		Internet-Draft G. Harrison
	Intended status: Standards Track Cisco Systems		Intended status: Standards Track S. Jury
	Expires: September 22, 2013 D. Satterwhite		Expires: August 14, 2014 Cisco Systems
			D. Satterwhite
	Broadcom		Broadcom
	S. Jury		Febuary 10, 2014
	NetApp
	March 25, 2013
	Dynamic Link Exchange Protocol (DLEP)		Dynamic Link Exchange Protocol (DLEP)
	draft-ietf-manet-dlep-04		draft-ietf-manet-dlep-05
	Abstract		Abstract
	When routing devices rely on modems to effect communications over		When routing devices rely on modems to effect communications over
	wireless links, they need timely and accurate knowledge of the		wireless links, they need timely and accurate knowledge of the
	characteristics of the link (speed, state, etc.) in order to make		characteristics of the link (speed, state, etc.) in order to make
	forwarding decisions. In mobile or other environments where these		forwarding decisions. In mobile or other environments where these
	characteristics change frequently, manual configurations or the		characteristics change frequently, manual configurations or the
	inference of state through routing or transport protocols does not		inference of state through routing or transport protocols does not
	allow the router to make the best decisions. A bidirectional, event-		allow the router to make the best decisions. A bidirectional, event-
	skipping to change at page 1, line 49 ¶		skipping to change at page 1, line 48 ¶
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	The list of current Internet-Drafts can be accessed at		The list of current Internet-Drafts can be accessed at
	http://www.ietf.org/ietf/1id-abstracts.txt.		http://www.ietf.org/ietf/1id-abstracts.txt.
	The list of Internet-Draft Shadow Directories can be accessed at		The list of Internet-Draft Shadow Directories can be accessed at
	http://www.ietf.org/shadow.html.		http://www.ietf.org/shadow.html.
	This Internet-Draft will expire on February 21, 2013.		This Internet-Draft will expire on August 14, 2014.
	Copyright Notice		Copyright Notice
	Copyright (c) 2012 IETF Trust and the persons identified as the		Copyright (c) 2012 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
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	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
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	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
	1.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . 7		1.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . 8
	2. Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . 7		2. Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	3. Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9		3. Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
	4. Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9		4. Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
	5. Extensions to DLEP . . . . . . . . . . . . . . . . . . . . . . 10		5. Extensions to DLEP . . . . . . . . . . . . . . . . . . . . . . 10
	6. Normal Session Flow . . . . . . . . . . . . . . . . . . . . . . 10		6. Normal Session Flow . . . . . . . . . . . . . . . . . . . . . 11
	7. Mandatory Signals and Data Items . . . . . . . . . . . . . . . 12		6.1 DLEP Modem session flow - Discovery case . . . . . . . . . . 11
	8. Generic DLEP Packet Definition . . . . . . . . . . . . . . . . 13		6.2 DLEP Modem session flow - Configured case . . . . . . . . . 11
	9. DLEP Data Items . . . . . . . . . . . . . . . . . . . . . . . . 13		6.3 DLEP Router session flow . . . . . . . . . . . . . . . . . 12
	9.1 DLEP Version . . . . . . . . . . . . . . . . . . . . . . . 14		6.4 Common Session Flow . . . . . . . . . . . . . . . . . . . . 12
	9.2 Peer Type . . . . . . . . . . . . . . . . . . . . . . . . . 15		7. Mandatory Signals and Data Items . . . . . . . . . . . . . . . 13
	9.3 MAC Address . . . . . . . . . . . . . . . . . . . . . . . . 15		8. Generic DLEP Message Definition . . . . . . . . . . . . . . . . 14
	9.4 IPv4 Address . . . . . . . . . . . . . . . . . . . . . . . 16		9. DLEP Data Items . . . . . . . . . . . . . . . . . . . . . . . . 15
	9.5 IPv6 Address . . . . . . . . . . . . . . . . . . . . . . . 17		9.1 DLEP Version . . . . . . . . . . . . . . . . . . . . . . . 16
	9.6 Maximum Data Rate (Receive) . . . . . . . . . . . . . . . . 17		9.2 DLEP Port . . . . . . . . . . . . . . . . . . . . . . . . . 17
	9.7 Maximum Data Rate (Transmit) . . . . . . . . . . . . . . . 18		9.3 Peer Type . . . . . . . . . . . . . . . . . . . . . . . . . 17
	9.8 Current Data Rate (Receive) . . . . . . . . . . . . . . . . 19		9.4 MAC Address . . . . . . . . . . . . . . . . . . . . . . . . 18
	9.9 Current Data Rate (Transmit) . . . . . . . . . . . . . . . 20		9.5 IPv4 Address . . . . . . . . . . . . . . . . . . . . . . . 18
	9.10 Expected Forwarding Time . . . . . . . . . . . . . . . . . 21		9.6 IPv6 Address . . . . . . . . . . . . . . . . . . . . . . . 19
	9.11 Latency . . . . . . . . . . . . . . . . . . . . . . . . . 21		9.7 Maximum Data Rate (Receive) . . . . . . . . . . . . . . . . 20
	9.12 Resources (Receive) . . . . . . . . . . . . . . . . . . . 22		9.8 Maximum Data Rate (Transmit) . . . . . . . . . . . . . . . 20
	9.13 Resources (Transmit) . . . . . . . . . . . . . . . . . . . 22		9.9 Current Data Rate (Receive) . . . . . . . . . . . . . . . . 21
	9.14 Relative Link Quality (Receive) . . . . . . . . . . . . . 23		9.10 Current Data Rate (Transmit) . . . . . . . . . . . . . . . 22
	9.15 Relative Link Quality (Transmit) . . . . . . . . . . . . . 24		9.11 Expected Forwarding Time . . . . . . . . . . . . . . . . . 23
	9.16 Status . . . . . . . . . . . . . . . . . . . . . . . . . . 24		9.12 Latency . . . . . . . . . . . . . . . . . . . . . . . . . 23
	9.17 Heartbeat Interval/Threshold . . . . . . . . . . . . . . . 25		9.13 Resources (Receive) . . . . . . . . . . . . . . . . . . . 24
	9.18 Link Characteristics ACK Timer . . . . . . . . . . . . . . 26		9.14 Resources (Transmit) . . . . . . . . . . . . . . . . . . . 25
	9.19 Credit Window Status . . . . . . . . . . . . . . . . . . . 26		9.15 Relative Link Quality (Receive) . . . . . . . . . . . . . 25
	9.20 Credit Grant Request . . . . . . . . . . . . . . . . . . . 27		9.16 Relative Link Quality (Transmit) . . . . . . . . . . . . . 26
	9.21 Credit Request . . . . . . . . . . . . . . . . . . . . . . 28		9.17 Status . . . . . . . . . . . . . . . . . . . . . . . . . . 26
			9.18 Heartbeat Interval . . . . . . . . . . . . . . . . . . . . 27
			9.19 Link Characteristics ACK Timer . . . . . . . . . . . . . . 28
			9.20 Credit Window Status . . . . . . . . . . . . . . . . . . . 28
			9.21 Credit Grant Request . . . . . . . . . . . . . . . . . . . 29
			9.22 Credit Request . . . . . . . . . . . . . . . . . . . . . . 30
			10. DLEP Protocol Messages . . . . . . . . . . . . . . . . . . . . 31
			10.1 Signal TLV Values . . . . . . . . . . . . . . . . . . . . 31
			10.2 Peer Discovery Message . . . . . . . . . . . . . . . . . . 32
			10.3 Peer Offer Message . . . . . . . . . . . . . . . . . . . . 32
			10.4 Peer Initialization Message . . . . . . . . . . . . . . . . 33
			10.5 Peer Initialization ACK Message . . . . . . . . . . . . . . 33
			10.6 Peer Update Message . . . . . . . . . . . . . . . . . . . . 34
			10.7 Peer Update ACK Message . . . . . . . . . . . . . . . . . . 35
			10.8 Peer Termination Message . . . . . . . . . . . . . . . . . 35
			10.9 Peer Termination ACK Message . . . . . . . . . . . . . . . 36
			10.10 Destination Up Message . . . . . . . . . . . . . . . . . . 36
			10.11 Destination Up ACK Message . . . . . . . . . . . . . . . . 37
			10.12 Destination Down Message . . . . . . . . . . . . . . . . . 37
			10.13 Destination Down ACK Message . . . . . . . . . . . . . . . 37
			10.14 Destination Update Message . . . . . . . . . . . . . . . . 38
			10.15 Heartbeat Message . . . . . . . . . . . . . . . . . . . . 38
			10.16 Link Characteristics Request Message . . . . . . . . . . . 39
			10.17 Link Characteristics ACK Message . . . . . . . . . . . . . 40
			11. Security Considerations . . . . . . . . . . . . . . . . . . . 40
			12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 40
			12.1 Registrations . . . . . . . . . . . . . . . . . . . . . . 41
			12.2 Expert Review: Evaluation Guidelines . . . . . . . . . . . 41
			12.3 Message (Signal) TLV Type Registration . . . . . . . . . . 41
			12.4 DLEP Data Item Registrations . . . . . . . . . . . . . . . 42
			12.5 DLEP Well-known Port . . . . . . . . . . . . . . . . . . . 42
			12.6 DLEP Multicast Address . . . . . . . . . . . . . . . . . . 42
			13. Appendix A. . . . . . . . . . . . . . . . . . . . . . . . . . 42
			13.1 Peer Level Message Flows . . . . . . . . . . . . . . . . . 42
			13.1.1 Modem Device Restarts Discovery . . . . . . . . . . . 43
			13.1.2 Modem Device Detects Peer Offer Timeout . . . . . . . 43
			13.1.3 Router Peer Offer Lost . . . . . . . . . . . . . . . . 44
			13.1.4 Discovery Success . . . . . . . . . . . . . . . . . . 44
			29.1.5 Router Detects a Heartbeat timeout . . . . . . . . . . 45
			29.1.6 Modem Detects a Heartbeat timeout . . . . . . . . . . 45
			29.1.7 Peer Terminate (from Modem) Lost . . . . . . . . . . . 46
			29.1.8 Peer Terminate (from Router) Lost . . . . . . . . . . 46
			29.2 Destination Specific Message Flows . . . . . . . . . . . . 46
			29.2.1 Modem Destination Up Lost . . . . . . . . . . . . . . 47
			29.2.2 Router Detects Duplicate Destination Ups . . . . . . . 47
			29.2.3 Destination Up, No Layer 3 Addresses . . . . . . . . . 48
			29.2.4 Destination Up with IPv4, No IPv6 . . . . . . . . . . 48
			29.2.5 Destination Up with IPv4 and IPv6 . . . . . . . . . . 48
			29.2.6 Destination Session Success . . . . . . . . . . . . . 49
	10. DLEP Protocol Messages . . . . . . . . . . . . . . . . . . . . 29		Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 49
	10.1 Signal TLV Values . . . . . . . . . . . . . . . . . . . . 29		Normative References . . . . . . . . . . . . . . . . . . . . . . . 50
	11. Peer Discovery Message . . . . . . . . . . . . . . . . . . . . 30		Informative References . . . . . . . . . . . . . . . . . . . . . . 50
	12. Peer Offer Message . . . . . . . . . . . . . . . . . . . . . . 31		Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 50
	13. Peer Offer ACK Message . . . . . . . . . . . . . . . . . . . . 31
	14. Peer Update Message . . . . . . . . . . . . . . . . . . . . . 32
	15. Peer Update ACK Message . . . . . . . . . . . . . . . . . . . 33
	16. Peer Termination Message . . . . . . . . . . . . . . . . . . . 33
	17. Peer Termination ACK Message . . . . . . . . . . . . . . . . . 33
	18. Neighbor Up Message . . . . . . . . . . . . . . . . . . . . . 34
	19. Neighbor Up ACK Message . . . . . . . . . . . . . . . . . . . 35
	20. Neighbor Down Message . . . . . . . . . . . . . . . . . . . . 35
	21. Neighbor Down ACK Message . . . . . . . . . . . . . . . . . . 35
	22. Neighbor Update Message . . . . . . . . . . . . . . . . . . . 36
	23. Heartbeat Message . . . . . . . . . . . . . . . . . . . . . . 36
	24. Link Characteristics Request Message . . . . . . . . . . . . . 37
	25. Link Characteristics ACK Message . . . . . . . . . . . . . . . 37
	26. Security Considerations . . . . . . . . . . . . . . . . . . . 38
	27. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 38
	27.1 Registrations . . . . . . . . . . . . . . . . . . . . . . 38
	27.2 Expert Review: Evaluation Guidelines . . . . . . . . . . . 39
	27.3 Signal (Message) TLV Type Registration . . . . . . . . . . 39
	27.4 DLEP Data Item Registrations . . . . . . . . . . . . . . . 39
	27.5 DLEP Well-known Port . . . . . . . . . . . . . . . . . . . 40
	27.6 DLEP Multicast Address . . . . . . . . . . . . . . . . . . 40
	30. Appendix A. . . . . . . . . . . . . . . . . . . . . . . . . . 40
	30.1 Peer Level Message Flows . . . . . . . . . . . . . . . . . 40
	30.1.1 Modem Device Restarts Discovery . . . . . . . . . . . 40
	30.1.2 Modem Device Detects Peer Offer Timeout . . . . . . . 41
	30.1.3 Router Peer Offer Lost . . . . . . . . . . . . . . . . 42
	30.1.4 Discovery Success . . . . . . . . . . . . . . . . . . 42
	30.1.5 Router Detects a Heartbeat timeout . . . . . . . . . . 43
	30.1.6 Modem Detects a Heartbeat timeout . . . . . . . . . . 43
	30.1.7 Peer Terminate (from Modem) Lost . . . . . . . . . . . 44
	30.1.8 Peer Terminate (from Router) Lost . . . . . . . . . . 44
	30.2 Neighbor Specific Message Flows . . . . . . . . . . . . . 44
	30.2.1 Modem Neighbor Up Lost . . . . . . . . . . . . . . . . 45
	30.2.2 Router Detects Duplicate Neighbor Ups . . . . . . . . 45
	30.2.3 Neighbor Up, No Layer 3 Addresses . . . . . . . . . . 46
	30.2.4 Neighbor Up with IPv4, No IPv6 . . . . . . . . . . . . 46
	30.2.5 Neighbor Up with IPv4 and IPv6 . . . . . . . . . . . . 46
	30.2.6 Neighbor Session Success . . . . . . . . . . . . . . . 47
	Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 47
	Normative References . . . . . . . . . . . . . . . . . . . . . . . 47
	Informative References . . . . . . . . . . . . . . . . . . . . . . 48
	Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 48
	1. Introduction		1. Introduction
	There exist today a collection of modem devices that control links of		There exist today a collection of modem devices that control links of
	variable bandwidth and quality. Examples of these types of links		variable datarate and quality. Examples of these types of links
	include line-of-sight (LOS) radios, satellite terminals, and		include line-of-sight (LOS) radios, satellite terminals, and
	cable/DSL modems. Fluctuations in speed and quality of these links		cable/DSL modems. Fluctuations in speed and quality of these links
	can occur due to configuration (in the case of cable/DSL modems), or		can occur due to configuration (in the case of cable/DSL modems), or
	on a moment-to-moment basis, due to physical phenomena like multipath		on a moment-to-moment basis, due to physical phenomena like multipath
	interference, obstructions, rain fade, etc. It is also quite possible		interference, obstructions, rain fade, etc. It is also quite possible
	that link quality and bandwidth varies with respect to individual		that link quality and datarate varies with respect to individual
	neighbors on a link, and with the type of traffic being sent. As an		destinations on a link, and with the type of traffic being sent. As
	example, consider the case of an 802.11g access point, serving 2		an example, consider the case of an 802.11g access point, serving 2
	associated laptop computers. In this environment, the answer to the		associated laptop computers. In this environment, the answer to the
	question "What is the bandwidth on the 802.11g link?" is "It depends		question "What is the datarate on the 802.11g link?" is "It depends
	on which associated laptop we're talking about, and on what kind of		on which associated laptop we're talking about, and on what kind of
	traffic is being sent." While the first laptop, being physically		traffic is being sent." While the first laptop, being physically
	close to the access point, may have a bandwidth of 54Mbps for unicast		close to the access point, may have a datarate of 54Mbps for unicast
	traffic, the other laptop, being relatively far away, or obstructed		traffic, the other laptop, being relatively far away, or obstructed
	by some object, can simultaneously have a bandwidth of only 32Mbps		by some object, can simultaneously have a datarate of only 32Mbps for
	for unicast. However, for multicast traffic sent from the access		unicast. However, for multicast traffic sent from the access point,
	point, all traffic is sent at the base transmission rate (which is		all traffic is sent at the base transmission rate (which is
	configurable, but depending on the model of the access point, is		configurable, but depending on the model of the access point, is
	usually 24Mbps or less).		usually 24Mbps or less).
	In addition to utilizing variable bandwidth links, mobile networks		In addition to utilizing variable datarate links, mobile networks are
	are challenged by the notion that link connectivity will come and go		challenged by the notion that link connectivity will come and go over
	over time. Effectively utilizing a relatively short-lived connection		time. Effectively utilizing a relatively short-lived connection is
	is problematic in IP routed networks, as routing protocols tend to		problematic in IP routed networks, as routing protocols tend to rely
	rely on independent timers at OSI Layer 3 to maintain network		on independent timers at OSI Layer 3 to maintain network convergence
	convergence (e.g. HELLO messages and/or recognition of DEAD routing		(e.g. HELLO messages and/or recognition of DEAD routing adjacencies).
	adjacencies). These short-lived connections can be better utilized		These short-lived connections can be better utilized with an event-
	with an event-driven paradigm, where acquisition of a new neighbor		driven paradigm, where acquisition of a new neighbor (or loss of an
	(or loss of an existing one) is signaled, as opposed to a timer-		existing one) is signaled, as opposed to a timer-driven paradigm.
	driven paradigm.
	Another complicating factor for mobile networks are the different		Another complicating factor for mobile networks are the different
	methods of physically connecting the modem devices to the router.		methods of physically connecting the modem devices to the router.
	Modems can be deployed as an interface card in a router's chassis, or		Modems can be deployed as an interface card in a router's chassis, or
	as a standalone device connected to the router via Ethernet, USB, or		as a standalone device connected to the router via Ethernet, USB, or
	even a serial link. In the case of Ethernet or serial attachment,		even a serial link. In the case of Ethernet or serial attachment,
	with existing protocols and techniques, routing software cannot be		with existing protocols and techniques, routing software cannot be
	aware of convergence events occurring on the radio link (e.g.		aware of convergence events occurring on the radio link (e.g.
	acquisition or loss of a potential routing neighbor), nor can the		acquisition or loss of a potential routing neighbor), nor can the
	router be aware of the actual capacity of the link. This lack of		router be aware of the actual capacity of the link. This lack of
	awareness, along with the variability in bandwidth, leads to a		awareness, along with the variability in datarate, leads to a
	situation where quality of service (QoS) profiles are extremely		situation where quality of service (QoS) profiles are extremely
	difficult to establish and properly maintain. This is especially true		difficult to establish and properly maintain. This is especially true
	of demand-based access schemes such as Demand Assigned Multiple		of demand-based access schemes such as Demand Assigned Multiple
	Access (DAMA) implementations used on some satellite systems. With a		Access (DAMA) implementations used on some satellite systems. With a
	DAMA-based system, additional bandwidth may be available, but will		DAMA-based system, additional datarate may be available, but will not
	not be used unless the network devices emit traffic at rate higher		be used unless the network devices emit traffic at rate higher than
	than the currently established rate. Increasing the traffic rate does		the currently established rate. Increasing the traffic rate does not
	not guarantee additional bandwidth will be allocated; rather, it may		guarantee additional datarate will be allocated; rather, it may
	result in data loss and additional retransmissions on the link.		result in data loss and additional retransmissions on the link.
	Addressing the challenges listed above, the authors have developed		Addressing the challenges listed above, the authors have developed
	the Data Link Exchange Protocol, or DLEP. The DLEP protocol runs		the Data Link Exchange Protocol, or DLEP. The DLEP protocol runs
	between a router and its attached modem devices, allowing the modem		between a router and its attached modem devices, allowing the modem
	to communicate link characteristics as they change, and convergence		to communicate link characteristics as they change, and convergence
	events (acquisition and loss of potential routing neighbors). The		events (acquisition and loss of potential routing destinations). The
	following diagrams are used to illustrate the scope of DLEP packets.		following diagrams are used to illustrate the scope of DLEP packets.
	|-------Local Node-------| |-------Remote Node------|		|-------Local Node-------| |-------Remote Node------|
	| | | |		| | | |
	+--------+ +-------+ +-------+ +--------+		+--------+ +-------+ +-------+ +--------+
	| Router |=======| Modem |{~~~~~~~~}| Modem |=======| Router |		| Router |=======| Modem |{~~~~~~~~}| Modem |=======| Router |
	| | | Device| | Device| | |		| | | Device| | Device| | |
	+--------+ +-------+ +-------+ +--------+		+--------+ +-------+ +-------+ +--------+
	| | | Link | | |		| | | Link | | |
	|-DLEP--| | Protocol | |-DLEP--|		|-DLEP--| | Protocol | |-DLEP--|
	skipping to change at page 5, line 35 ¶		skipping to change at page 5, line 41 ¶
	| | | 802.11) | | |		| | | 802.11) | | |
	Figure 1: DLEP Network		Figure 1: DLEP Network
	In Figure 1, when the local modem detects the presence of a remote		In Figure 1, when the local modem detects the presence of a remote
	node, it (the local modem) sends a signal to its router via the DLEP		node, it (the local modem) sends a signal to its router via the DLEP
	protocol. Upon receipt of the signal, the local router may take		protocol. Upon receipt of the signal, the local router may take
	whatever action it deems appropriate, such as initiating discovery		whatever action it deems appropriate, such as initiating discovery
	protocols, and/or issuing HELLO messages to converge the network. On		protocols, and/or issuing HELLO messages to converge the network. On
	a continuing, as-needed basis, the modem devices utilize DLEP to		a continuing, as-needed basis, the modem devices utilize DLEP to
	report any characteristics of the link (bandwidth, latency, etc) that		report any characteristics of the link (datarate, latency, etc) that
	have changed. DLEP is independent of the link type and topology		have changed. DLEP is independent of the link type and topology
	supported by the modem.		supported by the modem. Note that the DLEP protocol is specified to
			run only on the local link between router and modem. Some over the
			air signaling may be necessary between the local and remote modem in
			order to provide some parameters in DLEP messages between the local
			modem and local router, but DLEP does not specify how such over the
			air signaling is carried out. Over the air signaling is purely a
			matter for the modem implementer.
	Figure 2 shows how DLEP can support a configuration where routers are		Figure 2 shows how DLEP can support a configuration where routers are
	connected with different link types. In this example, Modem A		connected with different link types. In this example, Modem A
	implements a point-to-point link, and Modem B is connected via a		implements a point-to-point link, and Modem B is connected via a
	shared medium. In both cases, the DLEP protocol is used to report the		shared medium. In both cases, the DLEP protocol is used to report the
	characteristics of the link (bandwidth, latency, etc.) to routers.		characteristics of the link (datarate, latency, etc.) to routers. The
	The modem is also able to use the DLEP session to notify the router		modem is also able to use the DLEP session to notify the router when
	when the remote node is lost, shortening the time required to re-		the remote node is lost, shortening the time required to re-converge
	converge the network.		the network.
	+--------+ +--------+		+--------+ +--------+
	+----+ Modem A| | Modem A+---+		+----+ Modem A| | Modem A+---+
	| | Device | <===== // ======> | Device | |		| | Device | <===== // ======> | Device | |
	| +--------+ P-2-P Link +--------+ |		| +--------+ P-2-P Link +--------+ |
	+---+----+ +---+----+		+---+----+ +---+----+
	| Router | | Router |		| Router | | Router |
	| | | |		| | | |
	+---+----+ +---+----+		+---+----+ +---+----+
	| +--------+ +--------+ |		| +--------+ +--------+ |
	skipping to change at page 6, line 35 ¶		skipping to change at page 6, line 42 ¶
	+---+----+		+---+----+
	|		|
	|		|
	+---+----+		+---+----+
	| Router |		| Router |
	| |		| |
	+--------+		+--------+
	Figure 2: DLEP Network with Multiple Modem Devices		Figure 2: DLEP Network with Multiple Modem Devices
	DLEP defines a set of logical signals used by modems and their		DLEP defines a set of messages used by modems and their attached
	attached routers. The signals are used to communicate events that		routers. The messages are used to communicate events that occur on
	occur on the physical link(s) managed by the modem: for example, a		the physical link(s) managed by the modem: for example, a remote node
	remote node entering or leaving the network, or that the link has		entering or leaving the network, or that the link has changed.
	changed. Associated with these signals are a set of data items -		Associated with these messages are a set of data items - information
	information that describes the remote node (e.g., address		that describes the remote node (e.g., address information), and/or
	information), and/or the characteristics of the link to the remote		the characteristics of the link to the remote node.
	node.
	The protocol is defined as a collection of type-length-value (TLV)		The protocol is defined as a collection of type-length-value (TLV)
	based messages, specifying the signals that are exchanged between a		based messages, specifying the signals that are exchanged between a
	router and a modem, and the data items associated with the signal.		router and a modem, and the data items associated with the signal.
	This document specifies transport of DLEP signals and data items via		This document specifies transport of DLEP signals and data items via
	the UDP transport. Other transports for the protocol are possible,		the TCP transport, with a UDP-based discovery mechanism. Other
	but are outside the scope of this document.		transports for the protocol are possible, but are outside the scope
			of this document.
	DLEP signals are further defined as mandatory or optional. Signals		DLEP signals are further defined as mandatory or optional. Signals
	will additionally have mandatory and optional data items.		will additionally have mandatory and optional data items.
			Implementations MUST support all mandatory messages and their
	Implementations MUST support all mandatory signals and their
	mandatory data items to be considered compliant. Implementations MAY		mandatory data items to be considered compliant. Implementations MAY
	also support some, or all, of the optional signals and data items.		also support some, or all, of the optional messages and data items.
	DLEP uses a session-oriented paradigm between the modem device and		DLEP uses a session-oriented paradigm between the modem device and
	its associated router. If multiple modem devices are attached to a		its associated router. If multiple modem devices are attached to a
	router (as in Figure 2), a separate DLEP session MUST exist for each		router (as in Figure 2), a separate DLEP session MUST exist for each
	modem. If a modem device supports multiple connections to a router		modem. If a modem device supports multiple connections to a router
	(via multiple logical or physical interfaces), or supports		(via multiple logical or physical interfaces), or supports
	connections to multiple routers, a separate DLEP session MUST exist		connections to multiple routers, a separate DLEP session MUST exist
	for each connection. This router/modem session provides a carrier for		for each connection. This router/modem session provides a carrier for
	information exchange concerning neighbors (remote nodes) that are		information exchange concerning "destinations" that are available via
	accessible via the modem device. As such, all of the neighbor-level		the modem device. A "destination" can be either physical (as in the
	exchanges in DLEP can be envisioned as building an information base		case of a specific far-end router), or a logical destination (as in a
	concerning the remote nodes, and the link characteristics to those		Multicast group). As such, all of the destination-level exchanges in
	nodes.		DLEP can be envisioned as building an information base concerning the
			remote nodes, and the link characteristics to those nodes.
	Multicast traffic is handled in IP networks by deriving a Layer 2 MAC		Multicast traffic destined for the variable-quality network (the
	address based on the Layer 3 address. Leveraging on this scheme,		network accessed via the DLEP modem) is handled in IP networks by
	Multicast traffic is supported in DLEP simply by treating the derived		deriving a Layer 2 MAC address based on the Layer 3 address.
	MAC address as any other destination in the network. To support these		Leveraging on this scheme, Multicast traffic is supported in DLEP
	logical destinations, one of the DLEP participants (typically, the		simply by treating the derived MAC address as any other "destination"
	router) informs the other as to the existence of the logical		(albeit a logical one) in the network. To support these logical
	neighbor. The modem, once it is aware of the existence of this		destinations, one of the DLEP participants (typically, the router)
	logical neighbor, reports link characteristics just as it would for		informs the other as to the existence of the logical neighbor. The
	any other destination in the network. The specific algorithms a modem		modem, once it is aware of the existence of this logical neighbor,
	would use to report metrics on multicast (or logical) destinations is		reports link characteristics just as it would for any other
	outside the scope of this specification, and is left to specific		destination in the network. The specific algorithms a modem would use
			to report metrics on multicast (or logical) destinations is outside
			the scope of this specification, and is left to specific
	implementations to decide.		implementations to decide.
	1.1 Requirements		1.1 Requirements
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in BCP 14, RFC 2119		document are to be interpreted as described in BCP 14, RFC 2119
	[RFC2119].		[RFC2119].
	2. Assumptions		2. Assumptions
	skipping to change at page 8, line 5 ¶		skipping to change at page 8, line 24 ¶
	Routers and modems that exist as part of the same node (e.g., that		Routers and modems that exist as part of the same node (e.g., that
	are locally connected) can utilize a discovery technique to locate		are locally connected) can utilize a discovery technique to locate
	each other, thus avoiding a-priori configuration. The modem is		each other, thus avoiding a-priori configuration. The modem is
	responsible for initialing the discovery process, using the Peer		responsible for initialing the discovery process, using the Peer
	Discovery message.		Discovery message.
	DLEP utilizes a session-oriented paradigm. A router and modem form a		DLEP utilizes a session-oriented paradigm. A router and modem form a
	session by completing the discovery process. This router-modem		session by completing the discovery process. This router-modem
	session persists unless or until it either (1) times out, based on		session persists unless or until it either (1) times out, based on
	the timeout values supplied, or (2) is explicitly torn down by one of		the timeout values supplied, or (2) is explicitly torn down by one of
	the participants. Note that use of timers in DLEP is OPTIONAL; that		the participants. Note that while use of timers in DLEP is OPTIONAL,
	is, implementations can choose to run with no timers (or effectively,		it is strongly recommended that implementations choose to run with
	timers set to an infinite value).		timers enabled.
	DLEP assumes that participating modems, and their physical links, act		DLEP assumes that participating modems, and their physical links, act
	as a transparent bridge. Specifically, the assumption is that the		as a transparent bridge. Specifically, the assumption is that the
	destination MAC address for data traffic in any frame emitted by the		destination MAC address for data traffic in any frame emitted by the
	router should be the MAC address of a device in the remote node. DLEP		router should be the MAC address of a device in the remote node. DLEP
	also assumes that MAC addresses are unique within the context of the		also assumes that MAC addresses are unique within the context of the
	router-modem session.		router-modem session.
	This document refers to a remote node as a "Neighbor". Neighbors can		This document refers to a remote node as a "Destination".
	be identified by either the router or the modem, and represent a		Destinations can be identified by either the router or the modem, and
	specific destination (e.g., an address) that exists on the link(s)		represent a specific destination (e.g., an address) that exists on
	managed by the modem. Examples of a destination include a MAC		the link(s) managed by the modem. A destination MUST contain a MAC
	address, a unicast Layer 3 address, or a multicast Layer 3 address.		address, it MAY optionally include a Layer 3 address (or addresses).
	As "neighbors" are discovered, DLEP routers and modems build an		Destinations MAY refer either to physical devices in the network, or
	information base on destinations accessible via the modem. Changes in		to logical destinations, as in a multicast group. As "destinations"
	link characteristics MAY then be reported as being "modem-wide"		are discovered, DLEP routers and modems build an information base on
	(effecting ALL neighbors accessed via the modem) or MAY be neighbor		destinations accessible via the modem. Changes in link
			characteristics MAY then be reported as being "modem-wide" (effecting
			ALL destinations accessed via the modem) or MAY be neighbor
	(destination) specific.		(destination) specific.
	The DLEP signals concerning neighbors thus become the way for routers		The DLEP messages concerning destinations thus become the way for
	and modems to maintain, and notify each other about, an information		routers and modems to maintain, and notify each other about, an
	base representing the physical and logical (e.g., multicast)		information base representing the physical and logical (e.g.,
	destinations accessible via the modem device. The information base		multicast) destinations accessible via the modem device. The
	would contain addressing information (e.g., MAC address, and		information base would contain addressing information (e.g., MAC
	OPTIONALLY, Layer 3 addresses), link characteristics (metrics), and		address, and OPTIONALLY, Layer 3 addresses), link characteristics
	OPTIONALLY, flow control information (credits).		(metrics), and OPTIONALLY, flow control information (credits).
	DLEP assumes that security on the session (e.g. authentication of		DLEP assumes that security on the session (e.g. authentication of
	session partners, encryption of traffic, or both) is dealt with by		session partners, encryption of traffic, or both) is dealt with by
	the underlying transport mechanism (e.g., by using a transport such		the underlying transport mechanism (e.g., by using a transport such
	as DTLS [DTLS]).		as TLS [TLS]).
	Sequence Numbers for DLEP messages start at 0 and are incremented by
	one for each original and retransmitted message. The unsigned 16-bit
	Sequence Number rolls over at 65535 to 0. Sequence Numbers are unique
	within the context of a DLEP session. Sequence numbers are used in
	DLEP to correlate a response to a request.
	This document specifies an implementation of the DLEP signals and		This document specifies an implementation of the DLEP messages and
	data items running over the UDP transport, utilizing a well-known UDP		data items running over the TCP transport, utilizing a well-known TCP
	Port number. It is assumed that DLEP running over other transport		Port number. It is assumed that DLEP running over other transport
	mechanisms would be documented separately.		mechanisms would be documented separately.
	3. Credits		3. Credits
	DLEP includes an OPTIONAL credit-windowing scheme analogous to the		DLEP includes an OPTIONAL credit-windowing scheme analogous to the
	one documented in [RFC5578]. In this scheme, traffic between the		one documented in [RFC5578]. In this scheme, traffic between the
	router and modem is treated as two unidirectional windows. This		router and modem is treated as two unidirectional windows. This
	document identifies these windows as the "Modem Receive Window", or		document identifies these windows as the "Modem Receive Window", or
	MRW, and the "Router Receive Window", or RRW.		MRW, and the "Router Receive Window", or RRW.
	skipping to change at page 9, line 32 ¶		skipping to change at page 9, line 44 ¶
	always expressed as a 64-bit unsigned quantity.		always expressed as a 64-bit unsigned quantity.
	If used, credits are managed on a neighbor-specific basis; that is,		If used, credits are managed on a neighbor-specific basis; that is,
	separate credit counts are maintained for each neighbor requiring the		separate credit counts are maintained for each neighbor requiring the
	service. Credits do not apply to the DLEP session that exists between		service. Credits do not apply to the DLEP session that exists between
	routers and modems.		routers and modems.
	4. Metrics		4. Metrics
	DLEP includes the ability for the router and modem to communicate		DLEP includes the ability for the router and modem to communicate
	metrics that reflect the characteristics (e.g. bandwidth, latency) of		metrics that reflect the characteristics (e.g. datarate, latency) of
	the variable-quality link in use. As mentioned in the introduction		the variable-quality link in use. DLEP does NOT specify how a given
	section of this document, metrics have to be used within a context -		metric value is to be calculated, rather, the protocol assumes that
	for example, metrics to a unicast address in the network. DLEP allows		metrics have been calculated with a "best effort", incorporating all
	for metrics to be sent within two contexts - metrics for a specific		pertinent data that is available to the modem device.
	neighbor (those for a given destination within the network), and
	"modem-wide" (those that apply to all destinations accessed via the
	modem). Metrics supplied on DLEP Peer signals are, by definition,
	modem-wide; metrics supplied on Neighbor signals are, by definition,
	used for the specific neighbor only.
	Metrics are further subdivided into transmit and receive metrics.		As mentioned in the introduction section of this document, metrics
			have to be used within a context - for example, metrics to a unicast
			address in the network. DLEP allows for metrics to be sent within two
			contexts - metrics for a specific destination within the network
			(e.g., a specific router), and "modem-wide" (those that apply to all
			destinations accessed via the modem). Metrics are further subdivided
			into transmit and receive metrics. Metrics supplied on DLEP Peer
			signals are, by definition, modem-wide; metrics supplied on
			Destination messages signals are, by definition, used for the
			specific neighbor only.
			DLEP modem implementations MUST announce all supported metric items,
			and provide default values for those metrics, in the Peer
			Initialization message. In order to introduce a new metric type, DLEP
			modem implementations MUST terminate the session with the router (via
			the Peer Terminate message), and re-establish the session.
	It is left to implementations to choose sensible default values based		It is left to implementations to choose sensible default values based
	on their specific characteristics. Additionally, this mechanism		on their specific characteristics. Modems having static (non-
	(either at a modem-wide or specific neighbor context) MAY be used to		changing) link metric characteristics MAY report metrics only once
	report non-changing, or static, metrics. Modems having static link		for a given neighbor (or once on a modem-wide basis, if all
	metric characteristics MAY report metrics only once for a given		connections via the modem are of this static nature).
	neighbor (or once on a modem-wide basis, if all connections via the
	modem are of this static nature).
	The approach of allowing for different contexts for metric data		The approach of allowing for different contexts for metric data
	increases both the flexibility and the complexity of using metric		increases both the flexibility and the complexity of using metric
	data. This document details the mechanism whereby the data is		data. This document details the mechanism whereby the data is
	transmitted, however, the specific algorithms (precedence, etc) for		transmitted, however, the specific algorithms (precedence, etc) for
	utilizing the dual-context metrics is out of scope and not addressed		utilizing the dual-context metrics is out of scope and not addressed
	by this document.		by this document.
	5. Extensions to DLEP		5. Extensions to DLEP
	While this draft represents the best efforts of the co-authors, and		While this draft represents the best efforts of the co-authors, and
	the working group, to be functionally complete, it is recognized that		the working group, to be functionally complete, it is recognized that
	extensions to DLEP will in all likelihood be necessary as more link		extensions to DLEP will in all likelihood be necessary as more link
	types are utilized. To allow for future innovation, the draft		types are utilized. To allow for future innovation, the draft
	allocates numbering space for experimental implementations of both		allocates numbering space for experimental implementations of both
	signals and data items.		signals and data items.
	DLEP implementations MUST be capable of parsing and acting on the		DLEP implementations MUST be capable of parsing and acting on the
	mandatory signals and data items as documented in this specification.		mandatory messages and data items as documented in this
	DLEP signals/data items that are optional, or are in the experimental		specification. DLEP messages/data items that are optional, or are in
	numbering range SHOULD be silently dropped by an implementation if		the experimental numbering range SHOULD be silently dropped by an
	they are not understood.		implementation if they are not understood.
	The intent of the optional signals and data items, as well as the		The intent of the optional messages and data items, as well as the
	experimental numbering space, is to allow for further development of		experimental numbering space, is to allow for further development of
	DLEP protocol features and function. Having experimental space		DLEP protocol features and function. Having experimental space
	reserved for both signals and data items gives maximum flexibility		reserved for both signals and data items gives maximum flexibility
	for extending the protocol as conditions warrant. For example,		for extending the protocol as conditions warrant. For example,
	experimental data items could be used by implementations to send		experimental data items could be used by implementations to send
	additional metrics. A combination of experimental signals, and		additional metrics. A combination of experimental messages, and
	associated data items, could be used to implement new flow control		associated data items, could be used to implement new flow control
	schemes. If subsequent research and development define new features		schemes. If subsequent research and development define new features
	and function, then it should be standardized either as an update to		and function, then it should be standardized either as an update to
	this document, or as an additional stand-alone specification.		this document, or as an additional stand-alone specification.
	6. Normal Session Flow		6. Normal Session Flow
	At the start of a run, DLEP implementations (both router and modem)		Normal session flow is slightly different, depending on whether the
	initialize the communications path. In a UDP implementation, this		implementation represents a modem or a router, and whether discovery
	includes opening a socket and binding to the well-known port address		techniques are used. The normal flow by DLEP partner type is:
	(TBD). Once the communications path is established, modem
	implementations are free to issue a "Peer Discovery" message. The
	Peer Discovery MAY be sent either to the multicast address allocated
	for DLEP (TBD), or to a unicast address, obtained via a-priori
	configuration.
	Routers receiving a Peer Discovery message respond with a "Peer		6.1 DLEP Modem session flow - Discovery case
	Offer" signal to indicate readiness to participate in the DLEP
	session. The receiver of a Peer Offer message responds with a "Peer
	Offer ACK" message, completing discovery. While the Peer Discovery
	message MAY be sent to the DLEP multicast address (TBD), the Peer
	Offer, and all subsequent traffic, is sent to the unicast address
	that originated the Peer Discovery. Once the Peer Offer signal is
	acknowledged, both participants (router and modem) transition to the
	"in session" state, creating a logical, stateful session between the
	modem and the router. Subsequent DLEP signals are then processed
	within the context of this router/modem session. In the UDP-based
	implementation, traffic between DLEP modems and routers is correlated
	using the UDP 4-tuple (Source Address, Source Port, Destination
	Address, Destination Port). DLEP partners use these signals to build
	their respective information bases regarding destinations that are
	accessible via the modem, and link characteristics associated with
	those destinations.
	The "in session" state created by the discovery signals is maintained		If the DLEP modem implementation is utilizing the optional discovery
	until one of the following conditions occur:		mechanism, then the implementation will initialize a UDP socket,
			binding it to an arbitrary port. This UDP socket is used to send the
			Peer Discovery message to the DLEP link-local multicast address and
			port (TBD). The implementation then waits on receipt of a Peer Offer
			message, which MUST contain the unicast address and port for TCP-
			based communication with a DLEP router. The Peer Offer message MAY
			contain multiple address/port combinations. If more than one
			address/port combination is in the Peer Offer, the DLEP modem
			implementation SHOULD consider the list to be in priority sequence,
			with the "most desired" address/port combination listed first.
			However, modem implementations MAY use their own heuristics to
			determine the best address/port combination. At this point, the modem
			implementation MAY either destroy the UDP socket, or continue to
			issue Peer Discovery messages to the link-local address/port
			combination. In either case, the TCP session initialization occurs as
			in the configured case.
			6.2 DLEP Modem session flow - Configured case
			When a DLEP modem implementation has the address and port information
			for a TCP connection to the router (obtained either via configuration
			or via the discovery process described above), the modem will
			initialize and bind a TCP socket. This socket is used to connect to
			the DLEP router software. After a successful TCP connect, the modem
			implementation MUST issue a Peer Initialization message to the DLEP
			router. The Peer Initialization message MUST contain TLVs for ALL
			supported metrics from this modem (e.g. all MANDATORY metrics plus
			all OPTIONAL metrics supported by the implementation), along with the
			default values of those metrics. After sending the Peer
			Initialization, the modem implementation should wait for receipt of a
			Peer Initialization ACK message from the router. Receipt of the Peer
			Initialization ACK indicates that the router has received and
			processed the Peer Initialization, and the session MUST transition to
			the "in session" state. At this point, messages regarding
			destinations in the network, and/or Peer Update messages, can flow on
			the DLEP session between modem and router. The "in session" state is
			maintained until one of the following conditions occur:
	o The session is explicitly terminated (using Peer Termination), or		o The session is explicitly terminated (using Peer Termination), or
	o The session times out, based on supplied timeout values.		o The session times out, based on supplied timeout values.
	In order to maintain the session between router and modem, OPTIONAL		6.3 DLEP Router session flow
	periodic "Heartbeat" messages MAY be exchanged. These messages are
	intended to keep the session alive, and to verify bidirectional		DLEP router implementations MUST support the discovery mechanism.
	connectivity between the two participants. DLEP also provides for an		Therefore, the normal flow is as follows:
	OPTIONAL Peer Update message, intended to communicate some change in
	status (e.g., a change of layer 3 address parameters, or a modem-wide		The implementation will initialize a UDP socket, binding that socket
	link change).		to the DLEP link-local multicast address (TBD) and the DLEP well-
			known port number (also TBD). The implementation will then initialize
			a TCP socket, on a unicast address and port. This socket is used to
			listen for incoming TCP connection requests.
			When the router implementation receives a Peer Discovery message on
			the UDP socket, it responds by issuing a Peer Offer message to the
			sender of the Peer Discovery. The Peer Offer message MUST contain the
			unicast address and port of the TCP listen socket, described above. A
			DLEP router implementation MAY respond with ALL address/port
			combinations that have an active TCP listen posted. If multiple
			address/port combinations are listed, the receiver of the Peer Offer
			MAY connect on any available address/port pair. Anything other than
			Peer Discovery messages received on the UDP socket MUST be silently
			dropped.
			When the DLEP router implementation accepts a connection via TCP, it
			will wait for receipt of a Peer Initialization message. The received
			Peer Initialization MUST contain metric TLVs for ALL mandatory
			metrics, and MUST contain metric TLVs for ANY optional metrics
			supported by the modem. If a new metric is to be introduced, the DLEP
			session between router and modem MUST be terminated and restarted,
			and the new metric described in a Peer Initialization message.
			6.4 Common Session Flow
			In order to maintain the session between router and modem, periodic
			"Heartbeat" messages SHOULD be exchanged. These messages are intended
			to keep the session alive, and to verify bidirectional connectivity
			between the two participants. DLEP also provides for an OPTIONAL Peer
			Update message, intended to communicate some change in status (e.g.,
			a change of layer 3 address parameters, or a modem-wide link change).
	In addition to the messages above, the participants will transmit		In addition to the messages above, the participants will transmit
	DLEP messages concerning destinations in the network. These messages		DLEP messages concerning destinations in the network. These messages
	trigger creation/maintenance/deletion of "neighbors" in the		trigger creation/maintenance/deletion of destinations in the
	information base of the recipient. For example, a modem will inform		information base of the recipient. For example, a modem will inform
	its attached router of the presence of a new destination via the		its attached router of the presence of a new destination via the
	"Neighbor Up" signal. Receipt of a Neighbor Up causes the router to		"Destination Up" signal. Receipt of a Destination Up causes the
	allocate the necessary resources, creating an entry in the		router to allocate the necessary resources, creating an entry in the
	information base with the specifics (e.g., MAC Address, Latency, Data		information base with the specifics (e.g., MAC Address, Latency, Data
	Rate, etc) of the neighbor. The loss of a destination is communicated		Rate, etc) of the neighbor. The loss of a destination is communicated
	via the "Neighbor Down" signal, and changes in status to the		via the "Neighbor Down" signal, and changes in status to the
	destination (e.g. varying link quality, or addressing changes) are		destination (e.g. varying link quality, or addressing changes) are
	communicated via the "Neighbor Update" signal. The information on a		communicated via the "Neighbor Update" signal. The information on a
	given neighbor will persist in the router's information base until		given neighbor will persist in the router's information base until
	(1) a "Neighbor Down" is received, indicating that the modem has lost		(1) a "Neighbor Down" is received, indicating that the modem has lost
	contact with the remote node, or (2) the router/modem session		contact with the remote node, or (2) the router/modem session
	terminates, indicating that the router has lost contact with its own		terminates, indicating that the router has lost contact with its own
	local modem.		local modem.
	Again, metrics can be expressed within the context of a specific		Again, metrics can be expressed within the context of a specific
	neighbor via the Neighbor Update message, or on a modem-wide basis		neighbor via the Neighbor Update message, or on a modem-wide basis
	via the Peer Update message. In cases where metrics are provided on		via the Peer Update message. In cases where metrics are provided on
	the router/modem session, the receiver MUST propagate the metrics to		the router/modem session, the receiver MUST propagate the metrics to
	all neighbors in its information base that are accessed via the		all destinations in its information base that are accessed via the
	originator. A DLEP participant MAY send metrics both in a		originator. A DLEP participant MAY send metrics both in a
	router/modem session context (via the Peer Update message) and a		router/modem session context (via the Peer Update message) and a
	specific neighbor context (via Neighbor Update) at any time. The		specific neighbor context (via Neighbor Update) at any time. The
	heuristics for applying received metrics is left to implementations.		heuristics for applying received metrics is left to implementations.
	In addition to receiving metrics about the link, DLEP provides an		In addition to receiving metrics about the link, DLEP provides an
	OPTIONAL signal allowing a router to request a different amount of		OPTIONAL signal allowing a router to request a different datarate, or
	bandwidth, or latency, from the modem. This signal is referred to as		latency, from the modem. This signal is referred to as the Link
	the Link Characteristics Message, and gives the router the ability to		Characteristics Message, and gives the router the ability to deal
	deal with requisite increases (or decreases) of allocated		with requisite increases (or decreases) of allocated datarate/latency
	bandwidth/latency in demand-based schemes in a more deterministic		in demand-based schemes in a more deterministic manner.
	manner.
	7. Mandatory Signals and Data Items		7. Mandatory Signals and Data Items
	The following DLEP signals are considered core to the specification;		The following DLEP signals are considered core to the specification;
	implementations MUST support these signals, and the associated data		implementations MUST support these signals, and the associated data
	items, in order to be considered compliant:		items, in order to be considered compliant:
	Signal Data Items		Signal Data Items
	====== ==========		====== ==========
	Peer Discovery None		Peer Discovery (Modem Only) DLEP Version
			Peer Offer (Router Only) DLEP Version
			IPv4 or IPv6 address(es)
			DLEP Port
	Peer Offer None		Peer Initialization DLEP Version
			Maximum Data Rate (Receive)
			Maximum Data Rate (Transmit)
			Current Data Rate (Receive)
			Current Data Rate (Transmit)
			Latency
			Relative Link Quality (Receive)
			Relative Link Quality (Transmit)
	Peer Offer ACK Status		Peer Initialization ACK Status
	Peer Termination None		Peer Termination None
	Peer Termination ACK Status		Peer Termination ACK Status
	Neighbor Up MAC Address		Destination Up MAC Address
	Maximum Data Rate		Maximum Data Rate (Receive)
	Current Data Rate		Maximum Data Rate (Transmit)
			Current Data Rate (Receive)
			Current Data Rate (Transmit)
			Latency
			Relative Link Quality (Receive)
			Relative Link Quality (Transmit)
	Neighbor Update MAC Address		Destination Update MAC Address
	Maximum Data Rate		Maximum Data Rate (Receive)
	Current Data Rate		Maximum Data Rate (Transmit)
			Current Data Rate (Receive)
			Current Data Rate (Transmit)
			Latency
			Relative Link Quality (Receive)
			Relative Link Quality (Transmit)
	Neighbor Down MAC Address		Destination Down MAC Address
	All other DLEP signals and data items are OPTIONAL. Implementations		All other DLEP signals and data items are OPTIONAL. Implementations
	MAY choose to provide them. Implementations that do not support		MAY choose to provide them. Implementations that do not support
	optional signals and data items SHOULD parse, and silently drop, all		optional signals and data items SHOULD parse, and silently drop, all
	unsupported signals and/or data items.		unsupported messages and/or data items.
	8. Generic DLEP Packet Definition		8. Generic DLEP Message Definition
	The Generic DLEP Packet consists of a sequence of TLVs. The first TLV		The Generic DLEP Message consists of a sequence of TLVs. The first
	represents the signal being communicated (e.g., a "Neighbor Up", or a		TLV represents the signal being communicated (e.g., a "Destination
	"Peer Offer"). Subsequent TLVs contain the data items pertinent to		Up", or a "Peer Offer"). Subsequent TLVs contain the data items
	the signal (e.g., Maximum Data Rate, or Latency, etc).		pertinent to the signal (e.g., Maximum Data Rate, or Latency, etc).
	The Generic DLEP Packet Definition contains the following fields:		The Generic DLEP Packet Definition contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|Signal TLV Type | Length | DLEP data items... |		|Signal TLV Type | Length | DLEP data items... |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Signal - One of the DLEP Signal TLV type values		Signal - One of the DLEP Message TLV type values
	defined in this document.		defined in this document.
	Length - The length of all of the DLEP data items		Length - The length, expressed as a 16-bit
			quantity, of all of the DLEP data items
	associated with this signal.		associated with this signal.
	DLEP data items - One or more data items, encoded in TLVs,		DLEP data items - One or more data items, encoded in TLVs,
	as defined in this document.		as defined in this document.
	9. DLEP Data Items		9. DLEP Data Items
	As mentioned earlier, DLEP protocol messages are transported as a		As mentioned earlier, DLEP protocol messages are transported as a
	collection of TLVs. The first TLV present in a DLEP message MUST be		collection of TLVs. The first TLV present in a DLEP message MUST be
	one of the Signal TLVs, documented in section [INSERT REFERENCE		one of the Signal TLVs, documented in section 10. The signals are
	HERE]. The signals are followed by one or more data items, indicating		followed by one or more data items, indicating the specific changes
	the specific changes that need to be instantiated in the receiver's		that need to be instantiated in the receiver's information base.
	information base.
	Valid DLEP Data Items are:		Valid DLEP Data Items are:
	TLV TLV		TLV TLV
	Value Description		Value Description
	=========================================		=========================================
	TBD DLEP Version		TBD DLEP Version
			TBD DLEP Port
	TBD Peer Type		TBD Peer Type
	TBD IPv4 Address		TBD IPv4 Address
	TBD IPv6 Address		TBD IPv6 Address
	TBD Maximum Data Rate (Receive) (MDRR)		TBD Maximum Data Rate (Receive) (MDRR)
	TBD Maximum Data Rate (Transmit) (MDRT)		TBD Maximum Data Rate (Transmit) (MDRT)
	TBD Current Data Rate (Receive) (CDRR)		TBD Current Data Rate (Receive) (CDRR)
	TBD Current Data Rate (Transmit) (CDRT)		TBD Current Data Rate (Transmit) (CDRT)
	TBD Transmit Latency		TBD Latency
	TBD Receive Resources		TBD Receive Resources
	TBD Transmit Resources		TBD Transmit Resources
	TBD Expected Forwarding Time (EFT)		TBD Expected Forwarding Time (EFT)
	TBD Relative Link Quality (Receive) (RLQR)		TBD Relative Link Quality (Receive) (RLQR)
	TBD Relative Link Quality (Transmit) (RLQT)		TBD Relative Link Quality (Transmit) (RLQT)
	TBD Status		TBD Status
	TBD Heartbeat Interval/Threshold		TBD Heartbeat Interval/Threshold
	TBD Neighbor down ACK timer		TBD Neighbor down ACK timer
	TBD Link Characteristics ACK timer		TBD Link Characteristics ACK timer
	TBD Credit Window Status		TBD Credit Window Status
	skipping to change at page 14, line 39 ¶		skipping to change at page 16, line 33 ¶
	TLV Type - An 8-bit unsigned integer field specifying the data		TLV Type - An 8-bit unsigned integer field specifying the data
	item being sent.		item being sent.
	Length - An 8-bit length of the value field of the data item		Length - An 8-bit length of the value field of the data item
	Value - A field of length <Length> which contains data		Value - A field of length <Length> which contains data
	specific to a particular data item.		specific to a particular data item.
	9.1 DLEP Version		9.1 DLEP Version
	The DLEP Version TLV is an OPTIONAL TLV in both the Peer Discovery		The DLEP Version TLV is a MANDATORY TLV in Peer Discovery, Peer
	and Peer Offer messages. The Version TLV is used to indicate the		Offer, and Peer Initialization messages. The Version TLV is used to
	version of the protocol running in the originator. A participant MAY		indicate the version of the protocol running in the sender. The
	use this information to decide if the potential session partner is		receiver SHOULD use this information to decide if the potential
	running at a supported level.		session partner is running at a supported level.
	The DLEP Version TLV contains the following fields:		The DLEP Version TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length=4 | Major Version |		|TLV Type =TBD |Length=4 | Major Version |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Minor Version |		| Minor Version |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 15, line 9 ¶		skipping to change at page 17, line 4 ¶
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length=4 | Major Version |		|TLV Type =TBD |Length=4 | Major Version |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Minor Version |		| Minor Version |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - Length is 4		Length - Length is 4
	Major Version - Major version of the modem or router protocol.		Major Version - Major version of the modem or router protocol.
	Minor Version - Minor version of the modem or router protocol.		Minor Version - Minor version of the modem or router protocol.
	Support of this draft is indicated by setting the Major Version		Support of this draft is indicated by setting the Major Version
	to '1', and the Minor Version to '3' (e.g. Version 1.3).		to '1', and the Minor Version to '5' (i.e. Version 1.5).
	9.2 Peer Type		9.2 DLEP Port
			The DLEP Port TLV is a MANDATORY TLV in the Peer Offer message. The
			DLEP Port TLV is used to indicate the TCP Port number on the DLEP
			server available for connections. The receiver MUST use this
			information to perform the TCP connect to the DLEP server.
			The DLEP Port TLV contains the following fields:
			0 1 2 3
			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			|TLV Type =TBD |Length=2 | TCP Port Number |
			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			TLV Type - TBD
			Length - Length is 2
			TCP Port Number - TCP Port number on the DLEP server.
			Minor Version - Minor version of the modem or router protocol.
			9.3 Peer Type
	The Peer Type TLV is an OPTIONAL TLV in both the Peer Discovery and		The Peer Type TLV is an OPTIONAL TLV in both the Peer Discovery and
	Peer Offer messages. The Peer Type TLV is used by the router and		Peer Offer messages. The Peer Type TLV is used by the router and
	modem to give additional information as to its type. The peer type is		modem to give additional information as to its type. The peer type is
	a string and is envisioned to be used for informational purposes		a string and is envisioned to be used for informational purposes
	(e.g. as output in a display command).		(e.g. as output in a display command).
	The Peer Type TLV contains the following fields:		The Peer Type TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length= peer |Peer Type String |		|TLV Type =TBD |Length= peer |Peer Type String |
	| |type string len|Max Len = 80 |		| |type string len| |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - Length of peer type string (80 octets maximum).		Length - Length of peer type string.
	Peer Type String - Non-Null terminated string, maximum length of 80		Peer Type String - Non-Null terminated string, using UTF-8 encoding.
	octets. For example, a satellite modem might set		For example, a satellite modem might set this
	this variable to 'Satellite terminal'.		variable to 'Satellite terminal'.
	9.3 MAC Address		9.4 MAC Address
	The MAC address TLV MUST appear in all neighbor-oriented signals		The MAC address TLV MUST appear in all destination-oriented signals
	(e.g. Neighbor Up, Neighbor Up ACK, Neighbor Down, Neighbor Down ACK,		(e.g. Destination Up, Destination Up ACK, Destination Down,
	Neighbor Update, Link Characteristics Request, and Link		Destination Down ACK, Destination Update, Link Characteristics
	Characteristics ACK). The MAC Address TLV contains the address of the		Request, and Link Characteristics ACK). The MAC Address TLV contains
	destination on the remote node. The MAC address MAY be either a		the address of the destination on the remote node. The MAC address
	physical or a virtual destination. Examples of a virtual destination		MAY be either a physical or a virtual destination. Examples of a
	would be a multicast MAC address, or the broadcast MAC		virtual destination would be a multicast MAC address, or the
	(0xFFFFFFFFFFFF).		broadcast MAC (0xFFFFFFFFFFFF).
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 6 | MAC Address |		|TLV Type =TBD |Length = 6 | MAC Address |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| MAC Address |		| MAC Address |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 6		Length - 6
	MAC Address - MAC Address of the destination (either physical or		MAC Address - MAC Address of the destination (either physical or
	virtual).		virtual).
	9.4 IPv4 Address		9.5 IPv4 Address
	The IPv4 Address TLV is an OPTIONAL TLV. If supported, it MAY appear		The IPv4 Address TLV is an OPTIONAL TLV. If supported, it MAY appear
	in Neighbor Up, Neighbor Update, and Peer Update messages. When		in Destination Up, Destination Update, and Peer Update messages. When
	included in Neighbor messages, the IPv4 Address TLV contains the IPv4		included in Destination messages, the IPv4 Address TLV contains the
	address of the neighbor, as well as a subnet mask value. In the Peer		IPv4 address of the destination, as well as a subnet mask value. In
	Update message, it contains the IPv4 address of the originator of the		the Peer Update message, it contains the IPv4 address of the
	message. In either case, the TLV also contains an indication of		originator of the message. In either case, the TLV also contains an
	whether this is a new or existing address, or is a deletion of a		indication of whether this is a new or existing address, or is a
	previously known address.		deletion of a previously known address.
	The IPv4 Address TLV contains the following fields:		The IPv4 Address TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 6 | Add/Drop | IPv4 Address |		|TLV Type =TBD |Length = 6 | Add/Drop | IPv4 Address |
	| | | Indicator |		| | | Indicator |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| IPv4 Address | Subnet Mask |		| IPv4 Address | Subnet Mask |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 6		Length - 6
	Add/Drop - Value indicating whether this is a new or existing		Add/Drop - Value indicating whether this is a new or existing
	IPv4 address		address (0x01), or a withdrawal of an address (0x02).
	IPv4 Address - The IPv4 address of the neighbor or peer.		IPv4 Address - The IPv4 address of the destination or peer.
	Subnet Mask - A subnet mask (0-32) to be applied to the IPv4		Subnet Mask - A subnet mask (0-32) to be applied to the IPv4
	address.		address.
	9.5 IPv6 Address		9.6 IPv6 Address
	The IPv6 Address TLV is an OPTIONAL TLV. If supported, it MAY be used		The IPv6 Address TLV is an OPTIONAL TLV. If supported, it MAY be used
	in the Neighbor Up, Neighbor Update, Peer Discovery, and Peer Update		in the Destination Up, Destination Update, Peer Discovery, and Peer
	Messages. When included in Neighbor messages, this data item contains		Update Messages. When included in Destination messages, this data
	the IPv6 address of the neighbor. In the Peer Discovery and Peer		item contains the IPv6 address of the destination. In the Peer
	Update, it contains the IPv6 address of the originating peer. In		Discovery and Peer Update, it contains the IPv6 address of the
	either case, the data item also contains an indication of whether		originating peer. In either case, the data item also contains an
	this is a new or existing address, or is a deletion of a previously		indication of whether this is a new or existing address, or is a
	known address, as well as a subnet mask.		deletion of a previously known address, as well as a subnet mask.
	The IPv6 Address TLV contains the following fields:		The IPv6 Address TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 18 | Add/Drop | IPv6 Address |		|TLV Type =TBD |Length = 18 | Add/Drop | IPv6 Address |
	| | | Indicator | |		| | | Indicator | |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| IPv6 Address |		| IPv6 Address |
	skipping to change at page 17, line 45 ¶		skipping to change at page 20, line 15 ¶
	| IPv6 Address | Subnet Mask |		| IPv6 Address | Subnet Mask |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 18		Length - 18
	Add/Drop - Value indicating whether this is a new or existing		Add/Drop - Value indicating whether this is a new or existing
	address (0x01), or a withdrawal of an address (0x02).		address (0x01), or a withdrawal of an address (0x02).
	IPv6 Address - IPv6 Address of the neighbor or peer.		IPv6 Address - IPv6 Address of the destination or peer.
	Subnet Mask - A subnet mask value (0-128) to be applied to the Ipv6		Subnet Mask - A subnet mask value (0-128) to be applied to the Ipv6
	address.		address.
	9.6 Maximum Data Rate (Receive)		9.7 Maximum Data Rate (Receive)
	The Maximum Data Rate Receive (MDRR) TLV is used in Neighbor Up,
	Neighbor Update, Peer Discovery, Peer Update, and Link		The Maximum Data Rate Receive (MDRR) TLV is used in Destination Up,
			Destination Update, Peer Discovery, Peer Update, and Link
	Characteristics ACK Messages to indicate the maximum theoretical data		Characteristics ACK Messages to indicate the maximum theoretical data
	rate, in bits per second, that can be achieved while receiving data		rate, in bits per second, that can be achieved while receiving data
	on the link. When metrics are reported via the messages listed above,		on the link. When metrics are reported via the messages listed above,
	the maximum data rate receive MUST be reported. A value of 0 for the		the maximum data rate receive MUST be reported.
	MDRR indicates that the Maximum Data Rate Receive is currently
	'unknown'.
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 8 | MDRR (bps) |		|TLV Type =TBD |Length = 8 | MDRR (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| MDRR (bps) |		| MDRR (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| MDRR (bps) |		| MDRR (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 8		Length - 8
	Maximum Data Rate Receive - A 64-bit unsigned number, representing		Maximum Data Rate Receive - A 64-bit unsigned number, representing
	the maximum theoretical data rate, in bits per		the maximum theoretical data rate, in bits per
	second (bps), that can be achieved while		second (bps), that can be achieved while
	receiving on the link. An MDRR value of 0 MAY be		receiving on the link.
	used to indicate an 'unknown' data rate.
	9.7 Maximum Data Rate (Transmit)
	The Maximum Data Rate Transmit (MDRT) TLV is used in Neighbor Up,		9.8 Maximum Data Rate (Transmit)
	Neighbor Update, Peer Discovery, Peer Update, and Link		The Maximum Data Rate Transmit (MDRT) TLV is used in Destination Up,
			Destination Update, Peer Discovery, Peer Update, and Link
	Characteristics ACK Messages to indicate the maximum theoretical data		Characteristics ACK Messages to indicate the maximum theoretical data
	rate, in bits per second, that can be achieved while transmitting		rate, in bits per second, that can be achieved while transmitting
	data on the link. When metrics are reported via the messages listed		data on the link. When metrics are reported via the messages listed
	above, the maximum data rate transmit MUST be reported. A value of 0		above, the maximum data rate transmit MUST be reported.
	for the MDRT MAY be used to indicate that the Maximum Data Rate
	Transmit is currently unknown, or cannot be calculated.
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 8 | MDRT (bps) |		|TLV Type =TBD |Length = 8 | MDRT (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| MDRT (bps) |		| MDRT (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| MDRT (bps) |		| MDRT (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 8		Length - 8
	Maximum Data Rate Transmit - A 64-bit unsigned number, representing		Maximum Data Rate Transmit - A 64-bit unsigned number, representing
	the maximum theoretical data rate, in bits per		the maximum theoretical data rate, in bits per
	second (bps), that can be achieved while		second (bps), that can be achieved while
	transmitting on the link. An MDRT value of 0		transmitting on the link.
	indicates an 'unknown' data rate.
	9.8 Current Data Rate (Receive)		9.9 Current Data Rate (Receive)
	The Current Data Rate Receive (CDRR) TLV is used in Neighbor Up,		The Current Data Rate Receive (CDRR) TLV is used in Destination Up,
	Neighbor Update, Peer Discovery, Peer Update, Link Characteristics		Destination Update, Peer Discovery, Peer Update, Link Characteristics
	Request, and Link Characteristics ACK messages to indicate the rate		Request, and Link Characteristics ACK messages to indicate the rate
	at which the link is currently operating for receiving traffic. In		at which the link is currently operating for receiving traffic. The
	the case of the Link Characteristics Request, CDRR represents the		Current Data Rate Receive is a MANDATORY data item. In the case of
	desired receive data rate for the link. When metrics are reported via		the Link Characteristics Request, CDRR represents the desired receive
	the messages above (e.g. Neighbor Update), the current data rate		data rate for the link. When metrics are reported via the messages
	receive MUST be reported.		above (e.g. Destination Update), the current data rate receive MUST
			be reported.
	The Current Data Rate Receive TLV contains the following fields:		The Current Data Rate Receive TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |TLV Flags=0x10 |Length = 8 |CDRR (bps) |		|TLV Type =TBD |TLV Flags=0x10 |Length = 8 |CDRR (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| CDRR (bps) |		| CDRR (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 20, line 6 ¶		skipping to change at page 22, line 20 ¶
	Current Data Rate Receive - A 64-bit unsigned number, representing		Current Data Rate Receive - A 64-bit unsigned number, representing
	the current data rate, in bits per second, that		the current data rate, in bits per second, that
	is currently be achieved while receiving traffic		is currently be achieved while receiving traffic
	on the link. When used in the Link		on the link. When used in the Link
	Characteristics Request, CDRR represents the		Characteristics Request, CDRR represents the
	desired receive rate, in bits per second, on the		desired receive rate, in bits per second, on the
	link. If there is no distinction between current		link. If there is no distinction between current
	and maximum receive data rates, current data		and maximum receive data rates, current data
	rate receive SHOULD be set equal to the maximum		rate receive SHOULD be set equal to the maximum
	data rate receive. A CDRR value of 0 MAY be used		data rate receive.
	to indicate the CDRT is unknown, or cannot be
	calculated.
	9.9 Current Data Rate (Transmit)		9.10 Current Data Rate (Transmit)
	The Current Data Rate Receive (CDRT) TLV is used in Neighbor Up,		The Current Data Rate Receive (CDRT) TLV is used in Destination Up,
	Neighbor Update, Peer Discovery, Peer Update, Link Characteristics		Destination Update, Peer Discovery, Peer Update, Link Characteristics
	Request, and Link Characteristics ACK messages to indicate the rate		Request, and Link Characteristics ACK messages to indicate the rate
	at which the link is currently operating for transmitting traffic. In		at which the link is currently operating for transmitting traffic.
	the case of the Link Characteristics Request, CDRT represents the		Current Data Rate Transmit is a MANDATORY data item. In the case of
	desired transmit data rate for the link. When metrics are reported		the Link Characteristics Request, CDRT represents the desired
	via the messages above (e.g. Neighbor Update), the current data rate		transmit data rate for the link. When metrics are reported via the
			messages above (e.g. Destination Update), the current data rate
	transmit MUST be reported.		transmit MUST be reported.
	The Current Data Rate Transmit TLV contains the following fields:		The Current Data Rate Transmit TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |TLV Flags=0x10 |Length = 8 |CDRT (bps) |		|TLV Type =TBD |TLV Flags=0x10 |Length = 8 |CDRT (bps) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| CDRT (bps) |		| CDRT (bps) |
	skipping to change at page 20, line 46 ¶		skipping to change at page 23, line 12 ¶
	Current Data Rate Transmit - A 64-bit unsigned number, representing		Current Data Rate Transmit - A 64-bit unsigned number, representing
	the current data rate, in bits per second, that		the current data rate, in bits per second, that
	is currently be achieved while transmitting		is currently be achieved while transmitting
	traffic on the link. When used in the Link		traffic on the link. When used in the Link
	Characteristics Request, CDRT represents the		Characteristics Request, CDRT represents the
	desired transmit rate, in bits per second, on		desired transmit rate, in bits per second, on
	the link. If there is no distinction between		the link. If there is no distinction between
	current and maximum transmit data rates, current		current and maximum transmit data rates, current
	data rate transmit MUST be set equal to the		data rate transmit MUST be set equal to the
	maximum data rate transmit. A CDRT value of 0		maximum data rate transmit.
	MAY be used to indicate the CDRT is 'unknown',
	or cannot be calculated.
	9.10 Expected Forwarding Time		9.11 Expected Forwarding Time
	The Expected Forwarding Time (EFT) TLV is is an OPTIONAL data item.		The Expected Forwarding Time (EFT) TLV is is an OPTIONAL data item.
	If supported, it MAY be used in Neighbor Up, Neighbor Update, Peer		If supported, it MAY be used in Destination Up, Destination Update,
	Discovery, and Peer Update messages to indicate the typical latency		Peer Discovery, and Peer Update messages to indicate the typical
	between the arrival of a given packet at the transmitting device and		latency between the arrival of a given packet at the transmitting
	the reception of the packet at the other end of the link. EFT		device and the reception of the packet at the other end of the link.
	combines transmission time, idle time, waiting time, freezing time,		EFT combines transmission time, idle time, waiting time, freezing
	and queuing time to the degree that those values are meaningful to a		time, and queuing time to the degree that those values are meaningful
	given transmission medium.		to a given transmission medium.
	The Expected Forwarding Time TLV contains the following fields:		The Expected Forwarding Time TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 4 | EFT (ms) |		|TLV Type =TBD |Length = 4 | EFT (ms) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| EFT (ms) |		| EFT (ms) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 4		Length - 4
	EFT - A 32-bit unsigned number, representing the expected		EFT - A 32-bit unsigned number, representing the expected
	forwarding time, in milliseconds, on the link.		forwarding time, in milliseconds, on the link.
	9.11 Latency		9.12 Latency
	The Latency TLV is an OPTIONAL data item. If supported, it is used in		The Latency TLV is an MANDATORY data item. It is used in Peer
	Neighbor Up, Neighbor Update, Peer Discovery, Peer Update, Link		Initialization, Destination Up, Destination Update, Peer Discovery,
	Characteristics Request, and Link Characteristics ACK messages to		Peer Update, Link Characteristics Request, and Link Characteristics
	indicate the amount of latency on the link, or in the case of the		ACK messages to indicate the amount of latency on the link, or in the
	Link Characteristics Request, to indicate the maximum latency		case of the Link Characteristics Request, to indicate the maximum
	required on the link.		latency required on the link.
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 2 | Latency (ms) |		|TLV Type =TBD |Length = 2 | Latency (ms) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 2		Length - 2
	skipping to change at page 22, line 4 ¶		skipping to change at page 24, line 14 ¶
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 2 | Latency (ms) |		|TLV Type =TBD |Length = 2 | Latency (ms) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 2		Length - 2
	Latency - A 16-bit unsigned value, representing the transmission		Latency - A 16-bit unsigned value, representing the transmission
	delay that a packet encounters as it is transmitted		delay that a packet encounters as it is transmitted
	over the link. In Neighbor Up, Neighbor Update, and		over the link. In Destination Up, Destination Update,
	Link Characteristics ACK, this value is reported as		and Link Characteristics ACK, this value is reported
	delay, in milliseconds. The calculation of latency is		as delay, in milliseconds. The calculation of latency
	implementation dependent. For example, the latency may		is implementation dependent. For example, the latency
	be a running average calculated from the internal		may be a running average calculated from the internal
	queuing. If a device cannot calculate latency, this		queuing. If a device cannot calculate latency, this
	TLV SHOUD NOT be issued. In the Link Characteristics		TLV SHOUD NOT be issued. In the Link Characteristics
	Request Message, this value represents the maximum		Request Message, this value represents the maximum
	delay, in milliseconds, expected on the link.		delay, in milliseconds, expected on the link.
	9.12 Resources (Receive)		9.13 Resources (Receive)
	The Receive Resources TLV is an OPTIONAL data item. If supported, it		The Receive Resources TLV is an OPTIONAL data item. If supported, it
	is used in Neighbor Up, Neighbor Update, Peer Discovery, Peer Update,		is used in Destination Up, Destination Update, Peer Discovery, Peer
	and Link Characteristics ACK messages to indicate a percentage (0-		Update, and Link Characteristics ACK messages to indicate a
	100) amount of resources (e.g. battery power), committed to receiving		percentage (0-100) amount of resources (e.g. battery power),
	data, remaining on the originating peer.		committed to receiving data, remaining on the originating peer.
	The Resources TLV contains the following fields:		The Resources TLV contains the following fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 | Rcv Resources|		|TLV Type =TBD |Length = 1 | Rcv Resources|
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Receive Resources - A percentage, 0-100, representing the amount		Receive Resources - A percentage, 0-100, representing the amount
	of remaining resources, such as battery power,		of remaining resources, such as battery power,
	allocated to receiving data. A value of '0' MAY be		allocated to receiving data. If a device cannot
	used to indicate the receive resources are unknown or		calculate receive resources, this TLV SHOULD NOT be
	cannot be calculated.		issued.
	9.13 Resources (Transmit)		9.14 Resources (Transmit)
	The Transmit Resources TLV is an OPTIONAL data item. If supported, it		The Transmit Resources TLV is an OPTIONAL data item. If supported, it
	is used in Neighbor Up, Neighbor Update, Peer Discovery, Peer Update,		is used in Destination Up, Destination Update, Peer Discovery, Peer
	and Link Characteristics ACK messages to indicate a percentage (0-		Update, and Link Characteristics ACK messages to indicate a
	100) amount of resources (e.g. battery power), committed to		percentage (0-100) amount of resources (e.g. battery power),
	transmitting data, remaining on the originating peer.		committed to transmitting data, remaining on the originating peer.
	The Resources TLV contains the following fields:		The Resources TLV contains the following fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 | Xmt Resources|		|TLV Type =TBD |Length = 1 | Xmt Resources|
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Transmit Resources - A percentage, 0-100, representing the amount		Transmit Resources - A percentage, 0-100, representing the amount
	of remaining resources, such as battery power,		of remaining resources, such as battery power,
	allocated to transmitting data. A value of '0' MAY be		allocated to transmitting data. If the transmit
	used to indicate the transmit resources are unknown or		resources cannot be calculated, then the TLV SHOULD
	cannot be calculated.		NOT be issued.
	9.14 Relative Link Quality (Receive)		9.15 Relative Link Quality (Receive)
	The Relative Link Quality Receive (RLQR) TLV is an OPTIONAL data		The Relative Link Quality Receive (RLQR) TLV is a MANDATORY data
	item. If supported, it is used in Neighbor Up, Neighbor Update, Peer		item. If supported, it is used in Peer Initialization, Destination
	Discovery, Peer Update, and Link Characteristics ACK messages to		Up, Destination Update, Peer Discovery, Peer Update, and Link
	indicate the quality of the link for receiving data as calculated by		Characteristics ACK messages to indicate the quality of the link for
	the originating peer.		receiving data as calculated by the originating peer.
	The Relative Link Quality (Receive) TLV contains the following		The Relative Link Quality (Receive) TLV contains the following
	fields:		fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 |RCV Rel. Link |		|TLV Type =TBD |Length = 1 |RCV Rel. Link |
	| | |Quality (RLQR) |		| | |Quality (RLQR) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 23, line 42 ¶		skipping to change at page 26, line 4 ¶
	fields:		fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 |RCV Rel. Link |		|TLV Type =TBD |Length = 1 |RCV Rel. Link |
	| | |Quality (RLQR) |		| | |Quality (RLQR) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Relative Link Quality (Receive) - A non-dimensional number, 1-100,		Relative Link Quality (Receive) - A non-dimensional number, 1-100,
	representing relative link quality. A value of		representing relative link quality. A value of
	100 represents a link of the highest quality.		100 represents a link of the highest quality.
	A value of '0' indicated the RLQR is		If a device cannot calculate the RLQR, this
	'unknown', or cannot be calculated.		TLV SHOULD NOT be issued.
	9.15 Relative Link Quality (Transmit)		9.16 Relative Link Quality (Transmit)
	The Transmit Link Quality Receive (RLQT) TLV is an OPTIONAL data		The Transmit Link Quality Receive (RLQT) TLV is a MANDATORY data
	item. If supported, it is used in Neighbor Up, Neighbor Update, Peer		item. It is used in Peer Initialization, Destination Up, Destination
	Discovery, Peer Update, and Link Characteristics ACK messages to		Update, Peer Discovery, Peer Update, and Link Characteristics ACK
	indicate the quality of the link for transmitting data as calculated		messages to indicate the quality of the link for transmitting data as
	by the originating peer.		calculated by the originating peer.
	The Relative Link Quality (Transmit) TLV contains the following		The Relative Link Quality (Transmit) TLV contains the following
	fields:		fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 |XMT Rel. Link |		|TLV Type =TBD |Length = 1 |XMT Rel. Link |
	| | |Quality (RLQR) |		| | |Quality (RLQR) |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Relative Link Quality (Transmit) - A non-dimensional number, 1-100,		Relative Link Quality (Transmit) - A non-dimensional number, 1-100,
	representing relative link quality. A value of		representing relative link quality. A value of
	100 represents a link of the highest quality.		100 represents a link of the highest quality.
	A value of '0' indicated the RLQT is		If a device cannot calculate the RLQT, this
	'unknown', or cannot be calculated.		TLV SHOULD NOT be issued.
	9.16 Status		9.17 Status
	The Status TLV is sent as part of an acknowledgement message, from		The Status TLV is sent as part of an acknowledgement message, from
	either the modem or the router, to indicate the success or failure of		either the modem or the router, to indicate the success or failure of
	a given request.		a given request.
	The Status TLV contains the following fields:		The Status TLV contains the following fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 | Code |		|TLV Type =TBD |Length = 1 | Code |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Termination Code - 0 = Success, Non-zero = Failure. Specific values		Termination Code - 0 = Success, Non-zero = Failure. Specific values
	of a non-zero termination code depend on the		of a non-zero termination code depend on the
	operation requested (e.g. Neighbor Up,		operation requested (e.g. Destination Up,
	Neighbor Down, etc).		Destination Down, etc).
	9.17 Heartbeat Interval/Threshold		9.18 Heartbeat Interval
	The Heartbeat Interval/Threshold TLV is an OPTIONAL TLV. If		The Heartbeat Interval TLV is a MANDATORY TLV. It MUST be sent during
	supported, it MAY be sent during Peer Discovery to indicate the		Peer Initialization to indicate the desired Heartbeat timeout window.
	desired Heartbeat timeout window. If the modem includes the Heartbeat		The router MUST either accept the timeout interval supplied by the
	Interval TLV in Peer Discovery, the router MUST either accept the		modem, or reject the Peer Initialization, and close the socket.
	timeout interval supplied by the modem, or reject the Peer Discovery.		Implementations MUST implement heuristics such that DLEP signals
	Peer Discovery messages that do not include the Heartbeat Interval		sent/received reset the timer interval.
	TLV in Peer Discovery indicates a desire to establish the
	router/modem session without an activity timeout (e.g. an infinite
	timeout value). If an activity timeout is supported, implementations
	MAY choose to implement heuristics such that signals sent/received
	reset the timer window.
	The Interval is used to specify a period (in seconds) for Heartbeat		The Interval is used to specify a period (in seconds) for Heartbeat
	Messages (See Section 23). The Threshold value is used to indicate		Messages (See Section 23). By specifying an Interval value of 0,
	the desired number of windows, each of time (Heartbeat Interval)		implementations MAY indicates the desire to disable Heartbeat
	seconds, to wait before either participant declares the router/modem		messages entirely (e.g., the Interval is set to an infinite value),
	session lost. In this case, the overall amount of time before a		however, it is strongly recommended that implementations use non 0
	router/modem is declared lost is expressed as (Interval * Threshold).		timer values.
	Specifying an Interval value of 0 indicates the desire to disable
	Heartbeat messages entirely (e.g., the Interval is set to an infinite
	value). Setting the Threshold value to 0 is undefined, and TLVs with
	a Threshold value of 0 MUST be rejected by the recipient.
	The Heartbeat Interval/Threshold TLV contains the following fields:		A DLEP session will be considered inactive, and MUST be torn down, by
			an implementation detecting that two (2) Heartbeat intervals have
			transpired without receipt of any DLEP messages.
			The Heartbeat Interval TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 1 | Interval | Threshold |		|TLV Type =TBD |Length = 2 | Interval |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 2
	Interval - 0 = Do NOT use heartbeats on this peer-to-peer		Interval - 0 = Do NOT use heartbeats on this peer-to-peer
	session. Non-zero = Interval, in seconds, for		session. Non-zero = Interval, in seconds, for
	heartbeat messages.		heartbeat messages.
	Threshold - Number of windows, of Heartbeat Interval seconds,		9.19 Link Characteristics ACK Timer
	to wait before declaring a peer-to-peer session to
	be lost.
	9.18 Link Characteristics ACK Timer
	The Link Characteristics ACK Timer TLV is an OPTIONAL TLV. If		The Link Characteristics ACK Timer TLV is an OPTIONAL TLV. If
	supported, it MAY be sent during Peer Discovery to indicate the		supported, it MAY be sent during Peer Initialization to indicate the
	desired number of seconds to wait for a response to a Link		desired number of seconds to wait for a response to a Link
	Characteristics Request. If a router receives this TLV from a modem		Characteristics Request. If a router receives this TLV from a modem
	during Peer Discovery, the router MUST either accept the timeout		during Peer Discovery, the router MUST either accept the timeout
	value, or reject the Peer Discovery. If this TLV is omitted,		value, or reject the Peer Discovery. If this TLV is omitted,
	implementations supporting the Link Characteristics Request SHOULD		implementations supporting the Link Characteristics Request SHOULD
	choose a default value.		choose a default value.
	The Link Characteristics ACK Timer TLV contains the following fields:		The Link Characteristics ACK Timer TLV contains the following fields:
	0 1 2		0 1 2
	skipping to change at page 26, line 34 ¶		skipping to change at page 28, line 34 ¶
	TLV Type - TBD		TLV Type - TBD
	Length - 1		Length - 1
	Interval - 0 = Do NOT use timeouts for Link Characteristics		Interval - 0 = Do NOT use timeouts for Link Characteristics
	requests on this router/modem session. Non-zero =		requests on this router/modem session. Non-zero =
	Interval, in seconds, to wait before considering a		Interval, in seconds, to wait before considering a
	Link Characteristics Request has been lost.		Link Characteristics Request has been lost.
	9.19 Credit Window Status		9.20 Credit Window Status
	The Credit Window Status TLV is an OPTIONAL TLV. If credits are		The Credit Window Status TLV is an OPTIONAL TLV. If credits are
	supported by the DLEP participants (both the router and the modem),		supported by the DLEP participants (both the router and the modem),
	the Credit Window Status TLV MUST be sent by the participant		the Credit Window Status TLV MUST be sent by the participant
	receiving a Credit Grant Request for a given neighbor.		receiving a Credit Grant Request for a given destination.
	The Credit Window Status TLV contains the following fields:		The Credit Window Status TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 16 | Modem Receive Window Value |		|TLV Type =TBD |Length = 16 | Modem Receive Window Value |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Modem Receive Window Value |		| Modem Receive Window Value |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 27, line 24 ¶		skipping to change at page 29, line 23 ¶
	Modem Receive Window Value - A 64-bit unsigned number, indicating		Modem Receive Window Value - A 64-bit unsigned number, indicating
	the current (or initial) number of		the current (or initial) number of
	credits available on the Modem Receive		credits available on the Modem Receive
	Window.		Window.
	Router Receive Window Value - A 64-bit unsigned number, indicating		Router Receive Window Value - A 64-bit unsigned number, indicating
	the current (or initial) number of		the current (or initial) number of
	credits available on the Router Receive		credits available on the Router Receive
	Window.		Window.
	9.20 Credit Grant Request		9.21 Credit Grant Request
	The Credit Grant Request TLV is an OPTIONAL TLV. If credits are		The Credit Grant Request TLV is an OPTIONAL TLV. If credits are
	supported, the Credit Grant Request TLV is sent from a DLEP		supported, the Credit Grant Request TLV is sent from a DLEP
	participant to grant an increment to credits on a window. The Credit		participant to grant an increment to credits on a window. The Credit
	Grant TLV is sent as a data item in either the Neighbor Up or		Grant TLV is sent as a data item in either the Destination Up or
	Neighbor Update messages. The value in a Credit Grant TLV represents		Destination Update messages. The value in a Credit Grant TLV
	an increment to be added to any existing credits available on the		represents an increment to be added to any existing credits available
	window. Upon successful receipt and processing of a Credit Grant TLV,		on the window. Upon successful receipt and processing of a Credit
	the receiver MUST respond with a message containing a Credit Window		Grant TLV, the receiver MUST respond with a message containing a
	Status TLV to report the updated aggregate values for synchronization		Credit Window Status TLV to report the updated aggregate values for
	purposes.		synchronization purposes.
	In the Neighbor Up message, when credits are desired, the originating		In the Destination Up message, when credits are desired, the
	peer MUST set the initial credit value of the window it controls		originating peer MUST set the initial credit value of the window it
	(e.g. the Modem Receive Window, or Router Receive Window) to an		controls (e.g. the Modem Receive Window, or Router Receive Window) to
	initial, non-zero value. If the receiver of a Neighbor Up message		an initial, non-zero value. If the receiver of a Destination Up
	with a Credit Grant Request TLV supports credits, the receiver MUST		message with a Credit Grant Request TLV supports credits, the
	either reject the use of credits, via a Neighbor Up ACK response with		receiver MUST either reject the use of credits, via a Destination Up
	the correct Status TLV, or set the initial value from the data		ACK response with the correct Status TLV, or set the initial value
	contained in the Credit Window Status TLV. If the initialization		from the data contained in the Credit Window Status TLV. If the
	completes successfully, the receiver MUST respond to the Neighbor Up		initialization completes successfully, the receiver MUST respond to
	message with a Neighbor Up ACK message that contains a Credit Window		the Destination Up message with a Destination Up ACK message that
	Status TLV, initializing its receive window.		contains a Credit Window Status TLV, initializing its receive window.
	The Credit Grant TLV contains the following fields:		The Credit Grant TLV contains the following fields:
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 8 | Credit Increment |		|TLV Type =TBD |Length = 8 | Credit Increment |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Credit Increment |		| Credit Increment |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 28, line 30 ¶		skipping to change at page 30, line 28 ¶
	additional credits to be assigned to the credit		additional credits to be assigned to the credit
	window. Since credits can only be granted by the		window. Since credits can only be granted by the
	receiver on a window, the applicable credit window		receiver on a window, the applicable credit window
	(either the MRW or the RRW) is derived from the		(either the MRW or the RRW) is derived from the
	sender of the grant. The Credit Increment MUST NOT		sender of the grant. The Credit Increment MUST NOT
	cause the window to overflow; if this condition		cause the window to overflow; if this condition
	occurs, implementations MUST set the credit window		occurs, implementations MUST set the credit window
	to the maximum value contained in a 64-bit		to the maximum value contained in a 64-bit
	quantity.		quantity.
	9.21 Credit Request		9.22 Credit Request
	The Credit Request TLV is an OPTIONAL TLV. If credits are supported,		The Credit Request TLV is an OPTIONAL TLV. If credits are supported,
	the Credit Request TLV MAY be sent from either DLEP participant, via		the Credit Request TLV MAY be sent from either DLEP participant, via
	a Neighbor Update signal, to indicate the desire for the partner to		a Destination Update signal, to indicate the desire for the partner
	grant additional credits in order for data transfer to proceed on the		to grant additional credits in order for data transfer to proceed on
	session. If the corresponding Neighbor Up message for this session		the session. If the corresponding Destination Up message for this
	did NOT contain a Credit Window Status TLV, indicating that credits		session did NOT contain a Credit Window Status TLV, indicating that
	are to be used on the session, then the Credit Request TLV MUST be		credits are to be used on the session, then the Credit Request TLV
	rejected by the receiver via a Neighbor Update ACK message.		MUST be rejected by the receiver via a Destination Update ACK
			message.
	The Credit Request TLV contains the following fields:		The Credit Request TLV contains the following fields:
	0 1 2		0 1 2
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|TLV Type =TBD |Length = 0 | Reserved, MUST|		|TLV Type =TBD |Length = 0 | Reserved, MUST|
	| | | be set to 0 |		| | | be set to 0 |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	skipping to change at page 29, line 47 ¶		skipping to change at page 31, line 47 ¶
	10.1 Signal TLV Values		10.1 Signal TLV Values
	As mentioned above, all DLEP messages begin with the Type value of		As mentioned above, all DLEP messages begin with the Type value of
	the appropriate DLEP signal. Valid DLEP signals are:		the appropriate DLEP signal. Valid DLEP signals are:
	TLV TLV		TLV TLV
	Value Description		Value Description
	=========================================		=========================================
	TBD Peer Discovery		TBD Peer Discovery
	TBD Peer Offer		TBD Peer Offer
	TBD Peer Offer ACK		TBD Peer Initialization
	TBD Peer Update		TBD Peer Update
	TBD Peer Update ACK		TBD Peer Update ACK
	TBD Peer Termination		TBD Peer Termination
	TBD Peer Termination ACK		TBD Peer Termination ACK
	TBD Neighbor Up		TBD Destination Up
	TBD Neighbor Up ACK		TBD Destination Up ACK
	TBD Neighbor Down		TBD Destination Down
	TBD Neighbor Down ACK		TBD Destination Down ACK
	TBD Neighbor Update		TBD Destination Update
	TBD Heartbeat		TBD Heartbeat
	TBD Link Characteristics Request		TBD Link Characteristics Request
	TBD Link Characteristics ACK		TBD Link Characteristics ACK
	11. Peer Discovery Message		10.2 Peer Discovery Message
	The Peer Discovery Message is sent by a modem to begin a new DLEP
	association. The Peer Offer message is required to complete the
	discovery process. Implementations MAY implement their own retry
	heuristics in cases where it is determined the Peer Discovery Message
	has timed out. A Peer Discovery Message received from a modem that is
	already in session MUST be processed as if a Peer Termination Message
	had been received. A router implementation MAY then process the
	received Peer Discovery Message.
	Note that metric data items MAY be supplied with the Peer Discovery,		The Peer Discovery Message is sent by a modem to discover DLEP
	in order to populate default metric values, or to indicate a static,		routers in the network. The Peer Offer message is required to
	modem-wide environment. If metrics are supplied with the Peer		complete the discovery process. Implementations MAY implement their
	Discovery message, these metrics MUST be used as the initial values		own retry heuristics in cases where it is determined the Peer
	for all neighbors (remote nodes) established via the modem.		Discovery Message has timed out.
	Given the packet format described in section 11, the initial TLV Type		Given the packet format described in section 11, the initial TLV Type
	value is set to DLEP_PEER_DISCOVERY (value TBD). OPTIONAL TLVs are		value is set to DLEP_PEER_DISCOVERY (value TBD).
	then placed into the packet:
	Optional Data Item TLVs:		There are NO Data Item TLVs associated with the Peer Discovery
	- DLEP Version		message.
	- DLEP Peer Type
	- Heartbeat Interval
	- Heartbeat Threshold
	- Link Characteristics ACK Timer
	- Maximum Data Rate (Receive)
	- Maximum Data Rate (Transmit)
	- Current Data Rate (Receive)
	- Current Data Rate (Transmit)
	- Latency
	- Expected Forwarding Time
	- Resources (Receive)
	- Resources (Transmit)
	- Relative Link Quality (Receive)
	- Relative Link Quality (Transmit)
	12. Peer Offer Message		10.3 Peer Offer Message
	The Peer Offer Message is sent by a DLEP router in response to a Peer		The Peer Offer Message is sent by a DLEP router in response to a Peer
	Discovery Message. Upon receipt, and processing, of a Peer Offer		Discovery Message. Upon receipt, and processing, of a Peer Offer
	message, the modem MUST respond with a Peer Offer ACK message,		message, the modem responds by issuing a TCP connect to the
	completing the discovery phase of DLEP. Both DLEP participants		address/port combination specified in the received Peer Offer.
	(router and modem) would then enter an "in session" state. Any
	subsequent Discovery messages sent or received on this session MUST
	be considered an error, and the session MUST be terminated as if a
	Peer Termination Message had been received.
	The Peer Offer message MUST be sent to the unicast address of the		The Peer Offer message MUST be sent to the unicast address of the
	originator of Peer Discovery, regardless of whether the discovery was		originator of Peer Discovery.
	received on the DLEP multicast address (TBD) or on a unicast
	address.
	To construct a Peer Offer message, the initial TLV type value is set		To construct a Peer Offer message, the initial TLV type value is set
	to DLEP_PEER_OFFER (value TBD). The signal TLV is then followed by		to DLEP_PEER_OFFER (value TBD). The signal TLV is then followed by
	any OPTIONAL Data Item TLVs the implementation supports:		all MANDATORY Data Item TLVs, then by any OPTIONAL Data Item TLVs the
			implementation supports:
	Optional Data Item TLVs:
			Mandatory Data Item TLVs:
	- DLEP Version		- DLEP Version
			- Heartbeat Interval
			- At least one (1) IPv4 or IPv6 Address TLV
			- DLEP Port
			Optional Data Item TLVs:
	- Peer Type		- Peer Type
	- IPv4 Address
	- IPv6 Address
	- Status		- Status
	- Heartbeat Interval
	- Heartbeat Threshold
	- Link Characteristics ACK Timer
	13. Peer Offer ACK Message		10.4 Peer Initialization Message
	The Peer Offer ACK message acknowledges receipt of a Peer Offer		The Peer Initialization message is sent by a modem to start the DLEP
	message, and completes the router/modem session establishment for		TCP session. It is sent by the modem after a TCP connect to the
	DLEP. The Peer Offer ACK message MUST be sent to unicast address of		address/port combination in a received Peer Offer, or to an
	the originator of a Peer Offer message. The Peer Offer ACK message		address/port obtained from a-priori configuration.
	MUST contain an OPTIONAL Status data item, indicating success or
	failure of the attempt to establish a router/modem session.
	To construct a Peer Offer ACK message, the initial TLV type value is		All supported metric data items MUST be included in the Peer
	set to DLEP_PEER_OFFER_ACK (value TBD). Mandatory data item TLV's are		Initialization message, with default values to be used on a "modem-
	placed into the packet next:		wide" basis. This can be viewed as the modem "declaring" all
			supported metrics at DLEP session initialization. Receipt of any DLEP
			message containing a metric data item NOT included in Peer
			Initialization MUST be treated as an error, resulting in termination
			of the DLEP session between router and modem.
			To construct a Peer Initialization message, the initial TLV type
			value is set to DLEP_PEER_INIT (value TBD). The signal TLV is then
			followed by the required data items:
	Mandatory Data Item TLVs:		Mandatory Data Item TLVs:
	- Status		- DLEP Version
			- Heartbeat Interval
			- Maximum Data Rate Receive
			- Maximum Data Rate Transmit
			- Current Data Rate Receive
			- Current Data Rate Transmit
			- Latency
			- Relative Link Quality Receive
			- Relative Link Quality Transmit
			Optional Data Item TLVs:
			- Peer Type
			Note that metric data items MUST be supplied with the Peer
			Initialization, in order to populate default metric values. If, at
			any time, metrics are reported that were NOT in Peer Initialization,
			the receiving DLEP peer MUST treat this as a fatal error requiring
			termination of the DLEP session.
	Note that there are NO OPTIONAL data item TLVs specified for this		10.5 Peer Initialization ACK Message
	message.
	14. Peer Update Message		The Peer Initialization ACK message is a MANDATORY message, sent in
			response to a received Peer Initialization message. The Peer
			Initialization ACK message completes the TCP-level DLEP session
			establishment; the sender of the message should transition to an "in-
			session" state when the message is sent, and the receiver should
			transition to the "in-session" state upon receipt (and successful
			parsing) of Peer Initialization ACK.
			To construct a Peer Initialization ACK message, the initial TLV type
			value is set to DLEP_PEER_INIT_ACK (value TBD). The signal TLV is
			then followed by the required data items:
			Mandatory Data Item TLVs:
			- Status
			Optional Data Item TLVs:
			- Peer Type
			10.6 Peer Update Message
	The Peer Update message is an OPTIONAL message, sent by a DLEP peer		The Peer Update message is an OPTIONAL message, sent by a DLEP peer
	to indicate local Layer 3 address changes, or for metric changes on a		to indicate local Layer 3 address changes, or for metric changes on a
	modem-wide basis. For example, addition of an IPv4 address to the		modem-wide basis. For example, addition of an IPv4 address to the
	router would prompt a Peer Update message to its attached DLEP		router MAY prompt a Peer Update message to its attached DLEP modems.
	modems. Also, a modem that changes its Maximum Data Rate for all		Also, a modem that changes its Maximum Data Rate for all destinations
	destinations MAY reflect that change via a Peer Update Message to its		MAY reflect that change via a Peer Update Message to its attached
	attached router(s).		router(s).
	Concerning Layer 3 addresses, if the modem is capable of		Concerning Layer 3 addresses, if the modem is capable of
	understanding and forwarding this information (via proprietary		understanding and forwarding this information (via proprietary
	mechanisms), the address update would prompt any remote DLEP modems		mechanisms), the address update would prompt any remote DLEP modems
	(DLEP-enabled modems in a remote node) to issue a "Neighbor Update"		(DLEP-enabled modems in a remote node) to issue a "Destination
	message to their local routers with the new (or deleted) addresses.		Update" message to their local routers with the new (or deleted)
	Modems that do not track Layer 3 addresses SHOULD silently parse and		addresses. Modems that do not track Layer 3 addresses SHOULD silently
	ignore the Peer Update Message. Modems that track Layer 3 addresses		parse and ignore the Peer Update Message. Modems that track Layer 3
	MUST acknowledge the Peer Update with a Peer Update ACK message.		addresses MUST acknowledge the Peer Update with a Peer Update ACK
	Routers receiving a Peer Update with metric changes MUST apply the		message. Routers receiving a Peer Update with metric changes MUST
	new metric to all neighbors (remote nodes) accessible via the modem.		apply the new metric to all destinations (remote nodes) accessible
	Supporting implementations are free to employ heuristics to		via the modem. Supporting implementations are free to employ
	retransmit Peer Update messages. The sending of Peer Update Messages		heuristics to retransmit Peer Update messages. The sending of Peer
	for Layer 3 address changes SHOULD cease when a either participant		Update Messages for Layer 3 address changes SHOULD cease when a
	(router or modem) determines that the other implementation does NOT		either participant (router or modem) determines that the other
	support Layer 3 address tracking.		implementation does NOT support Layer 3 address tracking.
	If metrics are supplied with the Peer Update message (e.g. Maximum		If metrics are supplied with the Peer Update message (e.g. Maximum
	Data Rate), these metrics are considered to be modem-wide, and		Data Rate), these metrics are considered to be modem-wide, and
	therefore MUST be applied to all neighbors in the information base		therefore MUST be applied to all destinations in the information base
	associated with the router/modem session.		associated with the router/modem session.
	To construct a Peer Update message, the initial TLV type value is set		To construct a Peer Update message, the initial TLV type value is set
	to DLEP_PEER_UPDATE (value TBD). The Signal TLV is followed by any		to DLEP_PEER_UPDATE (value TBD). The Signal TLV is followed by any
	OPTIONAL Data Item TLVs.		OPTIONAL Data Item TLVs.
	Optional Data Item TLVs:		Optional Data Item TLVs:
	- IPv4 Address		- IPv4 Address
	- IPv6 Address		- IPv6 Address
	- Maximum Data Rate (Receive)		- Maximum Data Rate (Receive)
	- Maximum Data Rate (Transmit)		- Maximum Data Rate (Transmit)
	- Current Data Rate (Receive)		- Current Data Rate (Receive)
	- Current Data Rate (Transmit)		- Current Data Rate (Transmit)
	- Latency		- Latency
	- Expected Forwarding Time		- Expected Forwarding Time
	- Resources (Receive)		- Resources (Receive)
	- Resources (Transmit)		- Resources (Transmit)
	- Relative Link Quality (Receive)		- Relative Link Quality (Receive)
	- Relative Link Quality (Transmit)		- Relative Link Quality (Transmit)
	15. Peer Update ACK Message		10.7 Peer Update ACK Message
	The Peer Update ACK message is an OPTIONAL message, and is sent by		The Peer Update ACK message is an OPTIONAL message, and is sent by
	implementations supporting Layer 3 address tracking and/or modem-wide		implementations supporting Layer 3 address tracking and/or modem-wide
	metrics to indicate whether a Peer Update Message was successfully		metrics to indicate whether a Peer Update Message was successfully
	processed. If the Peer Update ACK is issued, it MUST contain a Status		processed. If the Peer Update ACK is issued, it MUST contain a Status
	data item, indicating the success or failure of processing the		data item, indicating the success or failure of processing the
	received Peer Update.		received Peer Update.
	To construct a Peer Update ACK message, the initial TLV type value is		To construct a Peer Update ACK message, the initial TLV type value is
	set to DLEP_PEER_UPDATE_ACK (value TBD). The Status data item TLV is		set to DLEP_PEER_UPDATE_ACK (value TBD). The Status data item TLV is
	placed in the packet next, completing the Peer Update ACK.		placed in the packet next, completing the Peer Update ACK.
	Optional Data Item TLVs:		Mandatory Data Item TLVs:
	- Status		- Status
	Note that there are NO OPTIONAL data item TLVs specified for this		Note that there are NO OPTIONAL data item TLVs specified for this
	message.		message.
	16. Peer Termination Message		10.8 Peer Termination Message
	The Peer Termination Message is sent by a DLEP participant when the		The Peer Termination Message is sent by a DLEP participant when the
	router/modem session needs to be terminated. Implementations		router/modem session needs to be terminated. Implementations
	receiving a Peer Termination message MUST send a Peer Termination ACK		receiving a Peer Termination message MUST send a Peer Termination ACK
	message to confirm the termination process. The sender of a Peer		message to confirm the termination process. The sender of a Peer
	Termination message is free to define its heuristics in event of a		Termination message is free to define its heuristics in event of a
	timeout. The receiver of a Peer Termination Message MUST release all		timeout. The receiver of a Peer Termination Message MUST release all
	resources allocated for the router/modem session, and MUST eliminate		resources allocated for the router/modem session, and MUST eliminate
	all neighbors in the information base accessible via the router/modem		all destinations in the information base accessible via the
	pair represented by the session. Router and modem state machines are		router/modem pair represented by the session. Router and modem state
	returned to the "discovery" state. No Neighbor Down messages are		machines are returned to the "discovery" state. No Destination Down
	sent.		messages are sent.
	To construct a Peer Termination message, the initial TLV type value		To construct a Peer Termination message, the initial TLV type value
	is set to DLEP_PEER_TERMINATION (value TBD). The Signal TLV is		is set to DLEP_PEER_TERMINATION (value TBD). The Signal TLV is
	followed by any OPTIONAL Data Item TLVs the implementation supports:		followed by any OPTIONAL Data Item TLVs the implementation supports:
	Optional Data Item TLVs:		Optional Data Item TLVs:
	- Status		- Status
	17. Peer Termination ACK Message		10.9 Peer Termination ACK Message
	The Peer Termination Message ACK is sent by a DLEP peer in response		The Peer Termination Message ACK is sent by a DLEP peer in response
	to a received Peer Termination order. Receipt of a Peer Termination		to a received Peer Termination order. Receipt of a Peer Termination
	ACK message completes the teardown of the router/modem session.		ACK message completes the teardown of the router/modem session.
	To construct a Peer Termination ACK message, the initial TLV type		To construct a Peer Termination ACK message, the initial TLV type
	value is set to DLEP_PEER_TERMINATION_ACK (value TBD). The		value is set to DLEP_PEER_TERMINATION_ACK (value TBD). The
	Identification data item TLV is placed in the packet next, followed		Identification data item TLV is placed in the packet next, followed
	by any OPTIONAL TLVs the implementation supports:		by any OPTIONAL TLVs the implementation supports:
	Optional Data Item TLVs:		Optional Data Item TLVs:
	- Status		- Status
	18. Neighbor Up Message		10.10 Destination Up Message
	A DLEP participant sends the Neighbor Up message to report that a new		A DLEP participant sends the Destination Up message to report that a
	destination has been detected. A Neighbor Up ACK Message is required		new destination has been detected. A Destination Up ACK Message is
	to confirm a received Neighbor Up. A Neighbor Up message can be sent		required to confirm a received Destination Up. A Destination Up
	either by the modem, to indicate that a new remote node has been		message can be sent either by the modem, to indicate that a new
	detected, or by the router, to indicate the presence of a new logical		remote node has been detected, or by the router, to indicate the
	destination (e.g., a Multicast group) exists in the network.		presence of a new logical destination (e.g., a Multicast group)
			exists in the network.
	The sender of the Neighbor Up Message is free to define its retry		The sender of the Destination Up Message is free to define its retry
	heuristics in event of a timeout. When a Neighbor Up message is		heuristics in event of a timeout. When a Destination Up message is
	received and successfully parsed, the receiver should add knowledge		received and successfully parsed, the receiver should add knowledge
	of the new destination to its information base, indicating that the		of the new destination to its information base, indicating that the
	destination is accessible via the modem/router pair.		destination is accessible via the modem/router pair.
	To construct a Neighbor Up message, the initial TLV type value is set		To construct a Destination Up message, the initial TLV type value is
	to DLEP_NEIGHBOR_UP (value TBD). The MAC Address data item TLV is		set to DLEP_Destination_UP (value TBD). The MAC Address data item TLV
	placed in the packet next, followed by any supported OPTIONAL Data		is placed in the packet next, followed by any supported OPTIONAL Data
	Item TLVs into the packet:		Item TLVs into the packet:
	Optional Data Item TLVs:		Optional Data Item TLVs:
	- IPv4 Address		- IPv4 Address
	- IPv6 Address		- IPv6 Address
	- Maximum Data Rate (Receive)		- Maximum Data Rate (Receive)
	- Maximum Data Rate (Transmit)		- Maximum Data Rate (Transmit)
	- Current Data Rate (Receive)		- Current Data Rate (Receive)
	- Current Data Rate (Transmit)		- Current Data Rate (Transmit)
	- Latency		- Latency
	- Expected Forwarding Time		- Expected Forwarding Time
	- Resources (Receive)		- Resources (Receive)
	- Resources (Transmit)		- Resources (Transmit)
	- Relative Link Factor (Receive)		- Relative Link Factor (Receive)
	- Relative Link Factor (Transmit)		- Relative Link Factor (Transmit)
	- Credit Window Status		- Credit Window Status
	19. Neighbor Up ACK Message		10.11 Destination Up ACK Message
	A DLEP participant sends the Neighbor Up ACK Message to indicate		A DLEP participant sends the Destination Up ACK Message to indicate
	whether a Neighbor Up Message was successfully processed.		whether a Destination Up Message was successfully processed.
	To construct a Neighbor Up ACK message, the initial TLV type value is		To construct a Destination Up ACK message, the initial TLV type value
	set to DLEP_NEIGHBOR_UP_ACK (value TBD). The MAC Address data item		is set to DLEP_Destination_UP_ACK (value TBD). The MAC Address data
	TLV is placed in the packet next, containing the MAC address of the		item TLV is placed in the packet next, containing the MAC address of
	DLEP neighbor. The implementation would then place any supported		the DLEP destination. The implementation would then place any
	OPTIONAL Data Item TLVs into the packet:		supported OPTIONAL Data Item TLVs into the packet:
	Optional Data Item TLVs:		Optional Data Item TLVs:
	- Credit Window Status		- Credit Window Status
	20. Neighbor Down Message		10.12 Destination Down Message
	A DLEP peer sends the Neighbor Down message to report when a		A DLEP peer sends the Destination Down message to report when a
	destination (a remote node or a multicast group) is no longer		destination (a remote node or a multicast group) is no longer
	reachable. The Neighbor Down message MUST contain the MAC Address		reachable. The Destination Down message MUST contain the MAC Address
	data item TLV. Other TLVs as listed are OPTIONAL, and MAY be present		data item TLV. Other TLVs as listed are OPTIONAL, and MAY be present
	if an implementation supports them. A Neighbor Down ACK Message MUST		if an implementation supports them. A Destination Down ACK Message
	be sent by the recipient of a Neighbor Down message to confirm that		MUST be sent by the recipient of a Destination Down message to
	the relevant data has been removed from the information base. The		confirm that the relevant data has been removed from the information
	sender of the Neighbor Down message is free to define its retry		base. The sender of the Destination Down message is free to define
	heuristics in event of a timeout.		its retry heuristics in event of a timeout.
	To construct a Neighbor Down message, the initial TLV type value is		To construct a Destination Down message, the initial TLV type value
	set to DLEP_NEIGHBOR_DOWN (value TBD). The signal TLV is followed by		is set to DLEP_Destination_DOWN (value TBD). The signal TLV is
	the mandatory MAC Address data item TLV.		followed by the mandatory MAC Address data item TLV.
	Note that there are NO OPTIONAL data item TLVs for this message.		Note that there are NO OPTIONAL data item TLVs for this message.
	21. Neighbor Down ACK Message		10.13 Destination Down ACK Message
	A DLEP participant sends the Neighbor Down ACK Message to indicate		A DLEP participant sends the Destination Down ACK Message to indicate
	whether a received Neighbor Down Message was successfully processed.		whether a received Destination Down Message was successfully
	If successfully processed, the sender of the ACK MUST have removed		processed. If successfully processed, the sender of the ACK MUST have
	all entries in the information base that pertain to the referenced		removed all entries in the information base that pertain to the
	neighbor. As with the Neighbor Down message, there are NO OPTIONAL		referenced destination. As with the Destination Down message, there
	Data Item TLVs defined for the Neighbor Down ACK message.		are NO OPTIONAL Data Item TLVs defined for the Destination Down ACK
			message.
	To construct a Neighbor Down message, the initial TLV type value is		To construct a Destination Down message, the initial TLV type value
	set to DLEP_NEIGHBOR_DOWN_ACK (value TBD). The mandatory data item		is set to DLEP_Destination_DOWN_ACK (value TBD). The mandatory data
	TLVs follow:		item TLVs follow:
	- MAC Address Data item		- MAC Address Data item
	- Status data item		- Status data item
	22. Neighbor Update Message		10.14 Destination Update Message
	A DLEP participant sends the Neighbor Update message when it detects		A DLEP participant sends the Destination Update message when it
	some change in the information base for a given neighbor (remote node		detects some change in the information base for a given destination
	or multicast group). Some examples of changes that would prompt a		(remote node or multicast group). Some examples of changes that would
	Neighbor Update message are:		prompt a Destination Update message are:
	- Change in link metrics (e.g., Data Rates)		- Change in link metrics (e.g., Data Rates)
	- Layer 3 addressing change (for implementations that support it)		- Layer 3 addressing change (for implementations that support it)
	To construct a Neighbor Update message, the initial TLV type value is		To construct a Destination Update message, the initial TLV type value
	set to DLEP_NEIGHBOR_UPDATE (value TBD). Following the signal TLV are		is set to DLEP_Destination_UPDATE (value TBD). Following the signal
	the mandatory Data Item TLVs:		TLV are the mandatory Data Item TLVs:
	MAC Address data item TLV		MAC Address data item TLV
	After placing the mandatory data item TLV into the packet, the		After placing the mandatory data item TLV into the packet, the
	implementation would place any supported OPTIONAL data item TLVs.		implementation would place any supported OPTIONAL data item TLVs.
	Possible OPTIONAL data item TLVs are:		Possible OPTIONAL data item TLVs are:
	- IPv4 Address		- IPv4 Address
	- IPv6 Address		- IPv6 Address
	- Maximum Data Rate (Receive)		- Maximum Data Rate (Receive)
	- Maximum Data Rate (Transmit)		- Maximum Data Rate (Transmit)
	- Current Data Rate (Receive)		- Current Data Rate (Receive)
	- Current Data Rate (Transmit)		- Current Data Rate (Transmit)
	- Latency		- Latency
	- Resources (Receive)		- Resources (Receive)
	- Resources (Transmit)		- Resources (Transmit)
	- Relative Link Quality (Receive)		- Relative Link Quality (Receive)
	- Relative Link Quality (Transmit)		- Relative Link Quality (Transmit)
	- Credit Window Status		- Credit Window Status
	- Credit Grant		- Credit Grant
	- Credit Request		- Credit Request
	23. Heartbeat Message		10.15 Heartbeat Message
	A Heartbeat Message is sent by a DLEP participant every N seconds,		A Heartbeat Message is sent by a DLEP participant every N seconds,
	where N is defined in the "Heartbeat Interval" field of the discovery		where N is defined in the "Heartbeat Interval" field of the discovery
	message. Note that implementations omitting the Heartbeat Interval		message. Note that implementations setting the Heartbeat Interval to
	effectively set the interval to an infinite value, therefore, in		0 effectively set the interval to an infinite value, therefore, in
	those cases, this message would NOT be sent.		those cases, this message would NOT be sent.
	The message is used by participants to detect when a DLEP session		The message is used by participants to detect when a DLEP session
	partner (either the modem or the router) is no longer communicating.		partner (either the modem or the router) is no longer communicating.
	Participants SHOULD allow some integral number of heartbeat intervals		Participants SHOULD allow two (2) heartbeat intervals to expire with
	(default 4) to expire with no traffic on the router/modem session		no traffic on the router/modem session before initiating DLEP session
	before initiating DLEP session termination procedures.		termination procedures.
	To construct a Heartbeat message, the initial TLV type value is set		To construct a Heartbeat message, the initial TLV type value is set
	to DLEP_PEER_HEARTBEAT (value TBD). The signal TLV is followed by the		to DLEP_PEER_HEARTBEAT (value TBD). The signal TLV is followed by the
	mandatory Heartbeat Interval/Threshold data item.		mandatory Heartbeat Interval/Threshold data item.
	Note that there are NO OPTIONAL data item TLVs for this message.		Note that there are NO OPTIONAL data item TLVs for this message.
	24. Link Characteristics Request Message		10.16 Link Characteristics Request Message
	The Link Characteristics Request Message is an OPTIONAL message, and		The Link Characteristics Request Message is an OPTIONAL message, and
	is sent by the router to request that the modem initiate changes for		is sent by the router to request that the modem initiate changes for
	specific characteristics of the link. Since the request specifies a		specific characteristics of the link. The request can reference
	neighbor, it can reference either a real destination (e.g., a remote		either a real (e.g., a remote node), or a logical (e.g., a multicast
	node), or a logical destination (e.g., a multicast destination)		group) destination within the network.
	within the network.
	The Link Characteristics Request message contains either a Current		The Link Characteristics Request message contains either a Current
	Data Rate (CDRR or CDRT) TLV to request a different amount of		Data Rate (CDRR or CDRT) TLV to request a different datarate than
	bandwidth than what is currently allocated, a Latency TLV to request		what is currently allocated, a Latency TLV to request that traffic
	that traffic delay on the link not exceed the specified value, or		delay on the link not exceed the specified value, or both. A Link
	both. A Link Characteristics ACK Message is required to complete the		Characteristics ACK Message is required to complete the request.
	request. Implementations are free to define their retry heuristics in		Implementations are free to define their retry heuristics in event of
	event of a timeout. Issuing a Link Characteristics Request with ONLY		a timeout. Issuing a Link Characteristics Request with ONLY the MAC
	the MAC Address TLV is a mechanism a peer MAY use to request metrics		Address TLV is a mechanism a peer MAY use to request metrics (via the
	(via the Link Characteristics ACK) from its partner.		Link Characteristics ACK) from its partner.
	To construct a Link Characteristics Request message, the initial TLV		To construct a Link Characteristics Request message, the initial TLV
	type value is set to DLEP_NEIGHBOR_LINK_CHAR_REQ (value TBD).		type value is set to DLEP_Destination_LINK_CHAR_REQ (value TBD).
	Following the signal TLV is the mandatory Data Item TLV:		Following the signal TLV is the mandatory Data Item TLV:
	MAC Address data item TLV		MAC Address data item TLV
	After placing the mandatory data item TLV into the packet, the		After placing the mandatory data item TLV into the packet, the
	implementation would place any supported OPTIONAL data item TLVs.		implementation would place any supported OPTIONAL data item TLVs.
	Possible OPTIONAL data item TLVs are:		Possible OPTIONAL data item TLVs are:
	Current Data Rate - If present, this value represents the NEW (or		Current Data Rate - If present, this value represents the NEW (or
	unchanged, if the request is denied) Current		unchanged, if the request is denied) Current
	Data Rate in bits per second (bps).		Data Rate in bits per second (bps).
	Latency - If present, this value represents the maximum		Latency - If present, this value represents the maximum
	desired latency (e.g., it is a not-to-exceed		desired latency (e.g., it is a not-to-exceed
	value) in milliseconds on the link.		value) in milliseconds on the link.
	25. Link Characteristics ACK Message		10.17 Link Characteristics ACK Message
	The LInk Characteristics ACK message is an OPTIONAL message, and is		The LInk Characteristics ACK message is an OPTIONAL message, and is
	sent by modems supporting it to the router letting the router know		sent by modems supporting it to the router letting the router know
	the success or failure of a requested change in link characteristics.		the success or failure of a requested change in link characteristics.
	The Link Characteristics ACK message SHOULD contain a complete set		The Link Characteristics ACK message SHOULD contain a complete set
	of metric data item TLVs. It MUST contain the same TLV types as the		of metric data item TLVs. It MUST contain the same TLV types as the
	request. The values in the metric data item TLVs in the Link		request. The values in the metric data item TLVs in the Link
	Characteristics ACK message MUST reflect the link characteristics		Characteristics ACK message MUST reflect the link characteristics
	after the request has been processed.		after the request has been processed.
	To construct a Link Characteristics Request ACK message, the initial		To construct a Link Characteristics Request ACK message, the initial
	TLV type value is set to DLEP_NEIGHBOR_LINK_CHAR_ACK (value TBD).		TLV type value is set to DLEP_Destination_LINK_CHAR_ACK (value TBD).
	Following the signal TLV is the mandatory Data Item TLV:		Following the signal TLV is the mandatory Data Item TLV:
	MAC Address data item TLV		MAC Address data item TLV
	After placing the mandatory data item TLV into the packet, the		After placing the mandatory data item TLV into the packet, the
	implementation would place any supported OPTIONAL data item TLVs.		implementation would place any supported OPTIONAL data item TLVs.
	Possible OPTIONAL data item TLVs are:		Possible OPTIONAL data item TLVs are:
	Current Data Rate - If present, this value represents the requested		Current Data Rate - If present, this value represents the requested
	data rate in bits per second (bps).		data rate in bits per second (bps).
	Latency - If present, this value represents the NEW		Latency - If present, this value represents the NEW
	maximum latency (or unchanged, if the request		maximum latency (or unchanged, if the request
	is denied), expressed in milliseconds, on the		is denied), expressed in milliseconds, on the
	link.		link.
	26. Security Considerations		11. Security Considerations
	The protocol does not contain any mechanisms for security (e.g.		The protocol does not contain any mechanisms for security (e.g.
	authentication or encryption). The protocol assumes that any security		authentication or encryption). The protocol assumes that any security
	would be implemented in the underlying transport (for example, by use		would be implemented in the underlying transport (for example, by use
	of DTLS or some other mechanism), and is therefore outside the scope		of DTLS or some other mechanism), and is therefore outside the scope
	of this document.		of this document.
	27. IANA Considerations		12. IANA Considerations
	This section specifies requests to IANA.		This section specifies requests to IANA.
	27.1 Registrations		12.1 Registrations
	This specification defines:		This specification defines:
	o A new repository for DLEP signals, with fifteen values currently		o A new repository for DLEP signals, with fifteen values currently
	assigned.		assigned.
	o Reservation of numbering space for Experimental DLEP signals.		o Reservation of numbering space for Experimental DLEP signals.
	o A new repository for DLEP Data Items, with twenty-one values		o A new repository for DLEP Data Items, with twenty-one values
	currently assigned.		currently assigned.
	o Reservation of numbering space in the Data Items repository for		o Reservation of numbering space in the Data Items repository for
	experimental data items.		experimental data items.
	o A request for allocation of a well-known port for DLEP		o A request for allocation of a well-known port for DLEP
	communication.		communication.
	o A request for allocation of a multicast address for DLEP		o A request for allocation of a multicast address for DLEP
	discovery.		discovery.
	27.2 Expert Review: Evaluation Guidelines		12.2 Expert Review: Evaluation Guidelines
	No additional guidelines for expert review are anticipated.		No additional guidelines for expert review are anticipated.
	27.3 Signal (Message) TLV Type Registration		12.3 Message (Signal) TLV Type Registration
	A new repository must be created with the values of the DLEP signals.		A new repository must be created with the values of the DLEP
	Valid signals are:		messages. Valid signals are:
	o Peer Discovery		o Peer Discovery
	o Peer Offer		o Peer Offer
	o Peer Offer ACK		o Peer Initialization
			o Peer Initialization ACK
	o Peer Update		o Peer Update
	o Peer Update ACK		o Peer Update ACK
	o Peer Termination		o Peer Termination
	o Peer Termination ACK		o Peer Termination ACK
	o Neighbor Up		o Destination Up
	o Neighbor Up ACK		o Destination Up ACK
	o Neighbor Down		o Destination Down
	o Neighbor Down ACK		o Destination Down ACK
	o Neighbor Update		o Destination Update
	o Heartbeat		o Heartbeat
	o Link Characteristics Request		o Link Characteristics Request
	o Link Characteristics ACK		o Link Characteristics ACK
	It is also requested that the repository contain space for		It is also requested that the repository contain space for
	experimental signal types.		experimental signal types.
	27.4 DLEP Data Item Registrations		12.4 DLEP Data Item Registrations
	A new repository for DLEP Data Items must be created. Valid Data		A new repository for DLEP Data Items must be created. Valid Data
	Items are:		Items are:
	o DLEP Version		o DLEP Version
	o Peer Type		o Peer Type
	o MAC Address		o MAC Address
	o IPv4 Address		o IPv4 Address
	o IPv6 Address		o IPv6 Address
	o Maximum Data Rate (Receive)		o Maximum Data Rate (Receive)
	skipping to change at page 40, line 30 ¶		skipping to change at page 42, line 38 ¶
	o Status		o Status
	o Heartbeat Interval/Threshold		o Heartbeat Interval/Threshold
	o Link Characteristics ACK Timer		o Link Characteristics ACK Timer
	o Credit Window Status		o Credit Window Status
	o Credit Grant		o Credit Grant
	o Credit Request		o Credit Request
	It is also requested that the registry allocation contain space for		It is also requested that the registry allocation contain space for
	experimental data items.		experimental data items.
	27.5 DLEP Well-known Port		12.5 DLEP Well-known Port
	It is requested that IANA allocate a well-known port number for DLEP		It is requested that IANA allocate a well-known port number for DLEP
	communication.		communication.
	27.6 DLEP Multicast Address		12.6 DLEP Multicast Address
	It is requested that IANA allocate a multicast address for DLEP		It is requested that IANA allocate a multicast address for DLEP
	discovery messages.		discovery messages.
	30. Appendix A.		13. Appendix A.
	30.1 Peer Level Message Flows
	30.1.1 Modem Device Restarts Discovery		13.1 Peer Level Message Flows
			13.1.1 Modem Device Restarts Discovery
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Discovery--------- Modem initiates discovery		<-------Peer Discovery--------- Modem initiates discovery
	---------Peer Offer-----------> Router detects a problem, sends		---------Peer Offer-----------> Router detects a problem, sends
	w/ Non-zero Status TLV Peer Offer w/Status TLV indicating		w/ Non-zero Status TLV Peer Offer w/Status TLV indicating
	the error.		the error.
	Modem accepts failure, restarts		Modem accepts failure, restarts
	discovery process.		discovery process.
	<-------Peer Discovery--------- Modem initiates discovery		<-------Peer Discovery--------- Modem initiates discovery
	---------Peer Offer-----------> Router accepts, sends Peer Offer		---------Peer Offer-----------> Router accepts, sends Peer Offer
	w/ Zero Status TLV w/ Status TLV indicating success.		w/ Zero Status TLV w/ Status TLV indicating success.
	Discovery completed.		Discovery completed.
	30.1.2 Modem Device Detects Peer Offer Timeout		13.1.2 Modem Device Detects Peer Offer Timeout
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Discovery--------- Modem initiates discovery, starts		<-------Peer Discovery--------- Modem initiates discovery, starts
	a guard timer.		a guard timer.
	Modem guard timer expires. Modem		Modem guard timer expires. Modem
	restarts discovery process.		restarts discovery process.
	<-------Peer Discovery--------- Modem initiates discovery, starts		<-------Peer Discovery--------- Modem initiates discovery, starts
	a guard timer.		a guard timer.
	---------Peer Offer-----------> Router accepts, sends Peer Offer		---------Peer Offer-----------> Router accepts, sends Peer Offer
	w/ Zero Status TLV w/ Status TLV indicating success.		w/ Zero Status TLV w/ Status TLV indicating success.
	Discovery completed.		Discovery completed.
	30.1.3 Router Peer Offer Lost		13.1.3 Router Peer Offer Lost
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Discovery--------- Modem initiates discovery, starts		<-------Peer Discovery--------- Modem initiates discovery, starts
	a guard timer.		a guard timer.
	---------Peer Offer-------|| Router offers availability		---------Peer Offer-------|| Router offers availability
	Modem times out on Peer Offer,		Modem times out on Peer Offer,
	skipping to change at page 42, line 28 ¶		skipping to change at page 44, line 28 ¶
	<-------Peer Discovery--------- Modem initiates discovery		<-------Peer Discovery--------- Modem initiates discovery
	---------Peer Offer-----------> Router detects subsequent		---------Peer Offer-----------> Router detects subsequent
	discovery, internally terminates		discovery, internally terminates
	the previous, accepts the new		the previous, accepts the new
	association, sends Peer Offer		association, sends Peer Offer
	w/Status TLV indicating success.		w/Status TLV indicating success.
	Discovery completed.		Discovery completed.
	30.1.4 Discovery Success		13.1.4 Discovery Success
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Discovery--------- Modem initiates discovery		<-------Peer Discovery--------- Modem initiates discovery
	---------Peer Offer-----------> Router offers availability		---------Peer Offer-----------> Router offers availability
	-------Peer Heartbeat--------->		<-----Peer Initialization------ Modem Connects on TCP Port
	<-------Peer Heartbeat---------		<------Peer Heartbeat----------
	-------Peer Heartbeat--------->		-------Peer Heartbeat--------->
	<==============================> Neighbor Sessions		<==============================> Message flow about destinations
			(i.e. Destination Up, Destination
			Down, Destination update)
	<-------Peer Heartbeat---------		<-------Peer Heartbeat---------
	-------Peer Heartbeat--------->		-------Peer Heartbeat--------->
	--------Peer Term Req---------> Terminate Request		--------Peer Term Req---------> Terminate Request
	<--------Peer Term Res--------- Terminate Response		<--------Peer Term Res--------- Terminate Response
	30.1.5 Router Detects a Heartbeat timeout		29.1.5 Router Detects a Heartbeat timeout
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Heartbeat---------		<-------Peer Heartbeat---------
	-------Peer Heartbeat--------->		-------Peer Heartbeat--------->
	||---Peer Heartbeat---------		||---Peer Heartbeat---------
	~ ~ ~ ~ ~ ~ ~		~ ~ ~ ~ ~ ~ ~
	-------Peer Heartbeat--------->		-------Peer Heartbeat--------->
	||---Peer Heartbeat---------		||---Peer Heartbeat---------
	Router Heartbeat Timer expires,		Router Heartbeat Timer expires,
	detects missing heartbeats. Router		detects missing heartbeats. Router
	takes down all neighbor sessions		takes down all destination sessions
	and terminates the Peer		and terminates the Peer
	association.		association.
	------Peer Terminate ---------> Peer Terminate Request		------Peer Terminate ---------> Peer Terminate Request
	Modem takes down all neighbor		Modem takes down all destination
	sessions, then acknowledges the		sessions, then acknowledges the
	Peer Terminate		Peer Terminate
	<----Peer Terminate ACK--------- Peer Terminate ACK		<----Peer Terminate ACK--------- Peer Terminate ACK
	30.1.6 Modem Detects a Heartbeat timeout		29.1.6 Modem Detects a Heartbeat timeout
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<-------Peer Heartbeat---------		<-------Peer Heartbeat---------
	-------Peer Heartbeat------||		-------Peer Heartbeat------||
	<-------Peer Heartbeat---------		<-------Peer Heartbeat---------
	~ ~ ~ ~ ~ ~ ~		~ ~ ~ ~ ~ ~ ~
	-------Peer Heartbeat------||		-------Peer Heartbeat------||
	<-------Peer Heartbeat---------		<-------Peer Heartbeat---------
	Modem Heartbeat Timer expires,		Modem Heartbeat Timer expires,
	detects missing heartbeats. Modem		detects missing heartbeats. Modem
	takes down all neighbor sessions		takes down all destination sessions
	<-------Peer Terminate-------- Peer Terminate Request		<-------Peer Terminate-------- Peer Terminate Request
	Router takes down all neighbor		Router takes down all destination
	sessions, then acknowledges the		sessions, then acknowledges the
	Peer Terminate		Peer Terminate
	------Peer Terminate ACK-----> Peer Terminate ACK		------Peer Terminate ACK-----> Peer Terminate ACK
	30.1.7 Peer Terminate (from Modem) Lost		29.1.7 Peer Terminate (from Modem) Lost
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	||------Peer Terminate-------- Modem Peer Terminate Request		||------Peer Terminate-------- Modem Peer Terminate Request
	Router Heartbeat times out,		Router Heartbeat times out,
	terminates association.		terminates association.
	--------Peer Terminate-------> Router Peer Terminate		--------Peer Terminate-------> Router Peer Terminate
	<-----Peer Terminate ACK------ Modem sends Peer Terminate ACK		<-----Peer Terminate ACK------ Modem sends Peer Terminate ACK
	30.1.8 Peer Terminate (from Router) Lost		29.1.8 Peer Terminate (from Router) Lost
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	-------Peer Terminate--------> Router Peer Terminate Request		-------Peer Terminate--------> Router Peer Terminate Request
	Modem HB times out,		Modem HB times out,
	terminates association.		terminates association.
	<------Peer Terminate-------- Modem Peer Terminate		<------Peer Terminate-------- Modem Peer Terminate
	------Peer Terminate ACK-----> Peer Terminate ACK		------Peer Terminate ACK-----> Peer Terminate ACK
	30.2 Neighbor Specific Message Flows		29.2 Destination Specific Message Flows
	30.2.1 Modem Neighbor Up Lost		29.2.1 Modem Destination Up Lost
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	||-----Neighbor Up ------------ Modem sends Neighbor Up		||-----Destination Up ------------ Modem sends Destination Up
	Modem timesout on ACK		Modem timesout on ACK
	<------Neighbor Up ------------ Modem sends Neighbor Up		<------Destination Up ------------ Modem sends Destination Up
	------Neighbor Up ACK---------> Router accepts the neighbor		------Destination Up ACK---------> Router accepts the destination
	session		session
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	. . . . . . . .		. . . . . . . .
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	30.2.2 Router Detects Duplicate Neighbor Ups		29.2.2 Router Detects Duplicate Destination Ups
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<------Neighbor Up ------------ Modem sends Neighbor Up		<------Destination Up ------------ Modem sends Destination Up
	------Neighbor Up ACK-------|| Router accepts the neighbor		------Destination Up ACK-------|| Router accepts the destination
	session		session
	Modem timesout on ACK		Modem timesout on ACK
	<------Neighbor Up ------------ Modem resends Neighbor Up		<------Destination Up ------------ Modem resends Destination Up
	Router detects duplicate Neighbor,		Router detects duplicate
	takes down the previous, accepts		Destination, takes down the
	the new Neighbor.		previous, accepts the new
			Destination.
	------Neighbor Up ACK---------> Router accepts the neighbor		------Destination Up ACK---------> Router accepts the destination
	session		session
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	. . . . . . . .		. . . . . . . .
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	30.2.3 Neighbor Up, No Layer 3 Addresses		29.2.3 Destination Up, No Layer 3 Addresses
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<------Neighbor Up ------------ Modem sends Neighbor Up		<------Destination Up ------------ Modem sends Destination Up
	------Neighbor Up ACK---------> Router accepts the neighbor		------Destination Up ACK---------> Router accepts the destination
	session		session
	Router ARPs for IPv4 if defined.		Router ARPs for IPv4 if defined.
	Router drives ND for IPv6 if		Router drives ND for IPv6 if
	defined.		defined.
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	. . . . . . . .		. . . . . . . .
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	30.2.4 Neighbor Up with IPv4, No IPv6		29.2.4 Destination Up with IPv4, No IPv6
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<------Neighbor Up ------------ Modem sends Neighbor Up with		<------Destination Up ------------ Modem sends Destination Up with
	the IPv4 TLV		the IPv4 TLV
	------Neighbor Up ACK---------> Router accepts the neighbor		------Destination Up ACK---------> Router accepts the destination
	session		session
	Router drives ND for IPv6 if		Router drives ND for IPv6 if
	defined.		defined.
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	. . . . . . . .		. . . . . . . .
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	30.2.5 Neighbor Up with IPv4 and IPv6		29.2.5 Destination Up with IPv4 and IPv6
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	<------Neighbor Up ------------ Modem sends Neighbor Up with		<------Destination Up ------------ Modem sends Destination Up with
	the IPv4 and IPv6 TLVs		the IPv4 and IPv6 TLVs
	------Neighbor Up ACK---------> Router accepts the neighbor		------Destination Up ACK---------> Router accepts the destination
	session		session
	<------Neighbor Update--------- Modem Neighbor Metrics		<------Destination Update--------- Modem Destination Metrics
	. . . . . . . .		. . . . . . . .
	30.2.6 Neighbor Session Success		29.2.6 Destination Session Success
	Router Modem Message Description		Router Modem Message Description
	====================================================================		====================================================================
	---------Peer Offer-----------> Router offers availability		---------Peer Offer-----------> Router offers availability
	-------Peer Heartbeat--------->		-------Peer Heartbeat--------->
	<------Neighbor Up ----------- Modem		<------Destination Up ----------- Modem
	------Neighbor Up ACK--------> Router		------Destination Up ACK--------> Router
	<------Neighbor Update--------- Modem		<------Destination Update--------- Modem
	. . . . . . . .		. . . . . . . .
	<------Neighbor Update--------- Modem		<------Destination Update--------- Modem
	Modem initiates the terminate		Modem initiates the terminate
	<------Neighbor Down ---------- Modem		<------Destination Down ---------- Modem
	------Neighbor Down ACK-------> Router		------Destination Down ACK-------> Router
	or		or
	Router initiates the terminate		Router initiates the terminate
	------Neighbor Down ----------> Router		------Destination Down ----------> Router
	<------Neighbor Down ACK------- Modem		<------Destination Down ACK------- Modem
	Acknowledgements		Acknowledgements
	The authors would like to acknowledge the influence and contributions		The authors would like to acknowledge and thank the members of the
	of Chris Olsen, Teco Boot, Subir Das, Jaewon Kang, Vikram Kaul, Rick		DLEP design team, who have provided invaluable insight. The members
	Taylor, John Dowdell, Nelson Powell, Bow-Nan Cheng, and Henning		of the design team are: Teco Boot, Bow-Nan Cheng, John Dowdell,
	Rogge.		Henning Rogge, and Rick Taylor.
			The authors would also like to acknowledge the influence and
			contributions of Chris Olsen, Martin Duke, Subir Das, Jaewon Kang,
			Vikram Kaul, and Nelson Powell.
	Normative References		Normative References
	[RFC5578] Berry, B., Ed., "PPPoE with Credit Flow and Metrics",		[RFC5578] Berry, B., Ed., "PPPoE with Credit Flow and Metrics",
	RFC 5578, February 2010.		RFC 5578, February 2010.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Informative References		Informative References
	[DTLS] Rescorla, E., Ed,. "Datagram Transport Layer Security",		[TLS] Dierks, T. and Rescorla, E. "The Transport Layer Security
	RFC 4347, April 2006.		(TLS) Protocol", RFC 5246, August 2008.
	Author's Addresses		Author's Addresses
	Stan Ratliff		Stan Ratliff
	Cisco		Cisco
	170 West Tasman Drive		170 West Tasman Drive
	San Jose, CA 95134		San Jose, CA 95134
	USA		USA
	EMail: sratliff@cisco.com		EMail: sratliff@cisco.com
	skipping to change at page 48, line 37 ¶		skipping to change at page 50, line 41 ¶
	EMail: boberry@cisco.com		EMail: boberry@cisco.com
	Greg Harrison		Greg Harrison
	Cisco		Cisco
	170 West Tasman Drive		170 West Tasman Drive
	San Jose, CA 95134		San Jose, CA 95134
	USA		USA
	EMail: greharri@cisco.com		EMail: greharri@cisco.com
	Shawn Jury		Shawn Jury
	NetApp		Cisco
	7301 Kit Creek Road, Building 2		170 West Tasman Drive
	Research Triangle Park, NC 27709		San Jose, CA 95134
	USA		USA
	Email: shawn.jury@netapp.com		Email: sjury@cisco.com
	Darryl Satterwhite		Darryl Satterwhite
	Broadcom		Broadcom
	USA		USA
	Email: dsatterw@broadcom.com		Email: dsatterw@broadcom.com
End of changes. 264 change blocks.
	719 lines changed or deleted		824 lines changed or added
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