< draft-ietf-bfd-unaffiliated-echo-00.txt		draft-ietf-bfd-unaffiliated-echo-01.txt >
	BFD Working Group W. Cheng		BFD Working Group W. Cheng
	Internet-Draft R. Wang		Internet-Draft R. Wang
	Updates: 5880 (if approved) China Mobile		Updates: 5880 (if approved) China Mobile
	Intended status: Standards Track X. Min		Intended status: Standards Track X. Min
	Expires: March 13, 2021 A. Liu		Expires: May 6, 2021 ZTE Corp.
	ZTE Corp.
	R. Rahman		R. Rahman
	Cisco Systems		Cisco Systems
	R. Boddireddy		R. Boddireddy
	Juniper Networks		Juniper Networks
	September 9, 2020		November 2, 2020
	Unaffiliated BFD Echo Function		Unaffiliated BFD Echo Function
	draft-ietf-bfd-unaffiliated-echo-00		draft-ietf-bfd-unaffiliated-echo-01
	Abstract		Abstract
	Bidirectional Forwarding Detection (BFD) is a fault detection		Bidirectional Forwarding Detection (BFD) is a fault detection
	protocol that can quickly determine a communication failure between		protocol that can quickly determine a communication failure between
	two forwarding engines. This document proposes a use of BFD echo		two forwarding engines. This document proposes a use of the BFD Echo
	where the local system supports BFD but the neighboring system does		function where the local system supports BFD but the neighboring
	not support BFD.		system does not support BFD.
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	provisions of BCP 78 and BCP 79.		provisions of BCP 78 and BCP 79.
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at https://datatracker.ietf.org/drafts/current/.		Drafts is at https://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	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."
	This Internet-Draft will expire on March 13, 2021.		This Internet-Draft will expire on May 6, 2021.
	Copyright Notice		Copyright Notice
	Copyright (c) 2020 IETF Trust and the persons identified as the		Copyright (c) 2020 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(https://trustee.ietf.org/license-info) in effect on the date of		(https://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	carefully, as they describe your rights and restrictions with respect		carefully, as they describe your rights and restrictions with respect
	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
	include Simplified BSD License text as described in Section 4.e of		include Simplified BSD License text as described in Section 4.e of
	the Trust Legal Provisions and are provided without warranty as		the Trust Legal Provisions and are provided without warranty as
	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
	2. Unaffiliated BFD Echo Behavior . . . . . . . . . . . . . . . 3		2. Updates to RFC 5880 . . . . . . . . . . . . . . . . . . . . . 3
	3. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . 4		3. Unaffiliated BFD Echo Procedures . . . . . . . . . . . . . . 6
	4. Security Considerations . . . . . . . . . . . . . . . . . . . 4		4. Unaffilicated BFD Echo Applicability . . . . . . . . . . . . 7
	5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4		5. Security Considerations . . . . . . . . . . . . . . . . . . . 8
	6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5		6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
	7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5		7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
	7.1. Normative References . . . . . . . . . . . . . . . . . . 5		8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 8
	7.2. Informative References . . . . . . . . . . . . . . . . . 5		9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 5		9.1. Normative References . . . . . . . . . . . . . . . . . . 8
			9.2. Informative References . . . . . . . . . . . . . . . . . 9
			Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
	1. Introduction		1. Introduction
	To minimize the impact of device faults on services and improve		To minimize the impact of device/link faults on services and improve
	network availability, a network device must be able to quickly detect		network availability, a network device must be able to quickly detect
	faults in communication with adjacent devices. Measures can then be		faults in communication with adjacent devices. Measures can then be
	taken to promptly rectify the faults to ensure service continuity.		taken to promptly rectify the faults to ensure service continuity.
	BFD [RFC5880] is a low-overhead, short-duration method to detect		BFD [RFC5880] is a low-overhead, short-duration method to detect
	faults on the path between adjacent forwarding engines. The faults		faults on the communication path between adjacent forwarding engines.
	can be interface, data link, and even forwarding engine faults. It		The faults can be on interface, data link, and even forwarding
	is a single, unified mechanism to monitor any media and protocol		engine. It is a single, unified mechanism to monitor any media and
	layers in real time.		protocol layers in real time.
	BFD defines asynchronous mode to satisfy various deployment		BFD defines Asynchronous mode to satisfy various deployment
	scenarios, also supports echo function to reduce the device		scenarios, and also supports Echo function to reduce the device
	requirement for BFD. When the echo function is activated, the local		requirement for BFD. When the Echo function is activated, the local
	system sends a BFD echo packet and the remote system loops back the		system sends BFD Echo packets and the remote system loops back the
	packet through the forwarding path. If several consecutive echo		received Echo packets through the forwarding path. If several
	packets are not received, the session is declared to be Down.		consecutive BFD Echo packets are not received by the local system,
			then the BFD session is declared to be Down.
	When using BFD echo function, it is not clear whether the devices		When using BFD Echo function, there are two typical scenarios as
	using echo function need to support the full BFD procotol, including		below:
	maintaining the state machine of BFD session as described in
	[RFC5880] and [RFC5881]. According to different understanding, there
	are two typical scenarios as below:
	1. Full BFD procotol capability with affiliated echo function:		o Full BFD protocol capability with affiliated Echo function: this
	this scenario requires both the local device and the neighboring		scenario requires both the local device and the neighboring device
	device to support BFD protocol.		to support full BFD protocol.
	2. Only BFD echo function without full BFD procotol capability:		o Only BFD Echo function without full BFD protocol capability:
	this scenario requires only the local device to support sending		this scenario requires only the local device to support sending
	BFD packets.		and demultiplexing BFD Control packets.
	The two typical scenarios are both reasonable and useful, and the		The two typical scenarios are both reasonable and useful, and the
	latter is referred to as unaffiliated BFD echo function in this		latter is referred to as Unaffiliated BFD Echo function in this
	document.		document.
	Unaffiliated BFD echo function described in this document reuses the
	BFD echo function as described in [RFC5880] and [RFC5881], but
	independent of BFD asynchronous mode, that means it doesn't need BFD
	protocol capability of state machine, but only BFD echo function to a
	deployed device supporting BFD detection. When using unaffiliated
	BFD echo function, just the local device works on BFD protocol and
	the BFD peer doesn't, which only loopback the received BFD echo
	packets as usual data packets without enabling BFD protocol.
	Section 6.2.2 of [BBF-TR-146] describes one use case of the		Section 6.2.2 of [BBF-TR-146] describes one use case of the
	unaffiliated BFD echo function, and at least one more use case is		Unaffiliated BFD Echo function, and at least one more use case is
	known in the field BFD deployment.		known in the field BFD deployment.
	2. Unaffiliated BFD Echo Behavior		This document describes the use of the Unaffiliated BFD Echo function
			over IPv4 and IPv6 for single IP hop.
	With the more and more application of BFD detection, there are some		2. Updates to RFC 5880
	scenarios the BFD echo function is deployed. And due to the
	different capabilities of the devices deploying BFD echo function,
	it's required to apply unaffiliated BFD echo to the devices that
	couldn't afford the overhead of the full BFD protocol capablity, such
	as the servers running virtual machines or some Internet of Things
	(IoT) devices. Unaffiliated BFD echo can be used when two devices
	are connected and only one of them supports BFD protocol capability.
	A BFD echo session can be established at the device that supports
	BFD, and the device will send the BFD echo packets with the IP
	address destined for itself, whereas the other peer device just
	loopback the received BFD echo packets.
	After receiving a BFD echo packet, the device that does not support		The Unaffiliated BFD Echo function described in this document reuses
	BFD protocol immediately loops back the packet by normal IP		the BFD Echo function as described in [RFC5880] and [RFC5881], but
	forwarding, implementing quick link failure detection. As shown in		does not require BFD asynchronous mode. When using the Unaffiliated
	Figure 1, device A supports BFD, whereas device B does not support		BFD Echo function, only the local system has the BFD protocol
	BFD. To rapidly detect any faults with the IP link between device A		enabled, the remote system just loops back the received BFD Echo
	and device B, a BFD echo session can be provisioned and created at		packets as regular data packets.
	device A, and device A starts sending BFD echo packets, which should
	include a BFD echo session demultiplexing field, such as BFD		With that said, this document updates [RFC5880] with respect to its
	discriminator defined in [RFC5880]. After receiving the BFD echo		descriptions on the BFD Echo function as follows.
	packets sent from device A, device B immediately loops back them,
	this allows device A to rapidly detect a connectivity loss to device		o [RFC5880] states in the 4th paragraph of Section 3.2:
	B.
			An adjunct to both modes is the Echo function. When the Echo
			function is active, a stream of BFD Echo packets is transmitted in
			such a way as to have the other system loop them back through its
			forwarding path. If a number of packets of the echoed data stream
			are not received, the session is declared to be down. The Echo
			function may be used with either Asynchronous or Demand mode.
			Since the Echo function is handling the task of detection, the
			rate of periodic transmission of Control packets may be reduced
			(in the case of Asynchronous mode) or eliminated completely (in
			the case of Demand mode).
			* This paragraph is now updated to:
			An adjunct or complement to both modes is the Echo function. When
			the Echo function is active, a stream of BFD Echo packets is
			transmitted in such a way as to have the other system loop them
			back through its forwarding path. If a number of packets of the
			echoed data stream are not received, the session is declared to be
			down. The Echo function may be used with either Asynchronous or
			Demand mode. Since the Echo function is handling the task of
			detection, the rate of periodic transmission of Control packets
			may be reduced (in the case of Asynchronous mode) or eliminated
			completely (in the case of Demand mode). The Echo function may
			also be used independently, with neither Asynchronous nor Demand
			mode.
			o [RFC5880] states in the 3rd and 9th paragraphs of Section 6.1:
			Once the BFD session is Up, a system can choose to start the Echo
			function if it desires and the other system signals that it will
			allow it. The rate of transmission of Control packets is
			typically kept low when the Echo function is active.
			If the session goes Down, the transmission of Echo packets (if
			any) ceases, and the transmission of Control packets goes back to
			the slow rate.
			* The two paragraphs are now updated to:
			When a system is running with Asynchronous mode, once the BFD
			session is Up, it can choose to start the Echo function if it
			desires and the other system signals that it will allow it. The
			rate of transmission of Control packets is typically kept low when
			the Echo function is active.
			In Asynchronous mode, if the session goes Down, the transmission
			of Echo packets (if any) ceases, and the transmission of Control
			packets goes back to the slow rate.
			o [RFC5880] states in the 2nd paragraph of Section 6.4:
			When a system is using the Echo function, it is advantageous to
			choose a sedate reception rate for Control packets, since liveness
			detection is being handled by the Echo packets. This can be
			controlled by manipulating the Required Min RX Interval field (see
			section 6.8.3).
			* This paragraph is now updated to:
			When a system is using the Echo function with Asynchronous mode,
			it is advantageous to choose a sedate reception rate for Control
			packets, since liveness detection is being handled by the Echo
			packets. This can be controlled by manipulating the Required Min
			RX Interval field (see section 6.8.3).
			o [RFC5880] states in the 2nd paragraph of Section 6.8:
			When a system is said to have "the Echo function active" it means
			that the system is sending BFD Echo packets, implying that the
			session is Up and the other system has signaled its willingness to
			loop back Echo packets.
			* This paragraph is now updated to:
			When a system in Asynchronous or Demand mode is said to have "the
			Echo function active" it means that the system is sending BFD Echo
			packets, implying that the session is Up and the other system has
			signaled its willingness to loop back Echo packets.
			o [RFC5880] states in the 7th paragraph of Section 6.8.3:
			When the Echo function is active, a system SHOULD set
			bfd.RequiredMinRxInterval to a value of not less than one second
			(1,000,000 microseconds). This is intended to keep received BFD
			Control traffic at a negligible level, since the actual detection
			function is being performed using BFD Echo packets.
			* This paragraph is now updated to:
			When the Echo function is active with Asynchronous mode, a system
			SHOULD set bfd.RequiredMinRxInterval to a value of not less than
			one second (1,000,000 microseconds). This is intended to keep
			received BFD Control traffic at a negligible level, since the
			actual detection function is being performed using BFD Echo
			packets.
			o [RFC5880] states in the 1st and 2nd paragraphs of Section 6.8.9:
			BFD Echo packets MUST NOT be transmitted when bfd.SessionState is
			not Up. BFD Echo packets MUST NOT be transmitted unless the last
			BFD Control packet received from the remote system contains a
			nonzero value in Required Min Echo RX Interval.
			BFD Echo packets MAY be transmitted when bfd.SessionState is Up.
			The interval between transmitted BFD Echo packets MUST NOT be less
			than the value advertised by the remote system in Required Min
			Echo RX Interval, except as follows:
			A 25% jitter MAY be applied to the rate of transmission, such
			that the actual interval MAY be between 75% and 100% of the
			advertised value. A single BFD Echo packet MAY be transmitted
			between normally scheduled Echo transmission intervals.
			* The two paragraphs are now updated to:
			When a system is using the Echo function with either Asynchronous
			or Demand mode, BFD Echo packets MUST NOT be transmitted when
			bfd.SessionState is not Up, and BFD Echo packets MUST NOT be
			transmitted unless the last BFD Control packet received from the
			remote system contains a nonzero value in Required Min Echo RX
			Interval.
			When a system is using the Echo function with either Asynchronous
			or Demand mode, BFD Echo packets MAY be transmitted when
			bfd.SessionState is Up, and the interval between transmitted BFD
			Echo packets MUST NOT be less than the value advertised by the
			remote system in Required Min Echo RX Interval, except as follows:
			A 25% jitter MAY be applied to the rate of transmission, such
			that the actual interval MAY be between 75% and 100% of the
			advertised value. A single BFD Echo packet MAY be transmitted
			between normally scheduled Echo transmission intervals.
			3. Unaffiliated BFD Echo Procedures
			As shown in Figure 1, device A supports BFD, whereas device B does
			not support BFD. To rapidly detect any IP forwarding faults between
			device A and device B, a BFD Echo session MUST be created at device
			A, and the BFD Echo session is RECOMMENDED to follow the BFD state
			machine defined in Section 6.2 of [RFC5880], except that the received
			state is not sent but echoed from the remote system. In this case,
			although BFD Echo packets are transmitted with destination UDP port
			3785 as defined in [RFC5881], the BFD Echo packets sent by device A
			are BFD Control packets too, the looped BFD Echo packets back from
			device B would drive BFD state change at device A, substituting the
			BFD Control packets sent from the BFD peer.
			Once a BFD Echo session is created at device A, it starts sending BFD
			Echo packets, which SHOULD include a BFD Echo session demultiplexing
			field, such as BFD Your Discriminator defined in [RFC5880] (BFD My
			Discriminator can be set to 0 to avoid confusion), except that device
			A can use IP source address or UDP source port to demultiplex BFD
			Echo session, or there is only one BFD Echo session running at device
			A. Device A would send BFD Echo packets with IP destination address
			destined for itself, such as the IP address of interface 1 of device
			A. All BFD Echo packets for the session MUST be sent with a Time to
			Live (TTL) or Hop Limit value of 255.
			Considering the BFD peer wouldn't advertise Required Min Echo RX
			Interval as defined in [RFC5880], the transmit interval for sending
			BFD Echo packets MUST be provisioned at device A, how to make sure
			the BFD peer is willing and able to loop back BFD Echo packets sent
			with the provisioned transmit interval is outside the scope of this
			document. Considering the BFD peer wouldn't advertise Detect Mult as
			defined in [RFC5880], the Detect Mult for calculating the Detection
			Time MUST be provisioned at device A, the Detection Time in device A
			is equal to the provisioned Detect Mult multiplied by the provisioned
			transmit interval.
			After receiving the BFD Echo packets sent from device A, the one-hop-
			away BFD peer device B immediately loops them back by normal IP
			forwarding, this allows device A to rapidly detect a connectivity
			loss to device B.
	Device A Device B		Device A Device B
	BFD echo session		BFD Echo session
	BFD Enabled BFD Echo packets loopback		BFD Enabled BFD Echo packets loopback
	+--------+ +---------+		+--------+ +---------+
	| A |---------------------------------| B |		| A |---------------------------------| B |
	| |Inf 1 Inf 1| |		| |Inf 1 Inf 1| |
	+--------+10.1.1.1/24 10.1.1.2/24+---------+		+--------+10.1.1.1/24 10.1.1.2/24+---------+
	BFD is supported. BFD is not supported.		BFD is supported. BFD is not supported.
	Figure 1: Unaffiliated BFD Echo deployment scenario		Figure 1: Unaffiliated BFD Echo deployment scenario
	3. Discussion		4. Unaffilicated BFD Echo Applicability
	Unaffiliated BFD echo function is reasonable and useful. Firstly,		With the more and more application of BFD detection, there are some
	unaffiliated BFD echo can use BFD protocol capability in the local		scenarios the BFD Echo function is deployed. And due to the
	BFD-supported device, while using IP forwarding capability in the		different capabilities of the devices deploying BFD Echo function,
	peer non-BFD-supported device, so unaffiliated BFD echo can support		it's required to apply Unaffiliated BFD Echo to the devices that
			couldn't afford the overhead of the full BFD protocol capability,
			such as the servers running virtual machines or some Internet of
			Things (IoT) devices. Unaffiliated BFD Echo can be used when two
			devices are connected and only one of them supports BFD protocol
			capability.
			Unaffiliated BFD Echo function is reasonable and useful. Firstly,
			Unaffiliated BFD Echo can use BFD protocol capability at the local
			BFD-supported device, while using IP forwarding capability at the
			peer BFD-unsupported device, so Unaffiliated BFD Echo can support
	fast detecting and manage BFD sessions very effectively. Secondly,		fast detecting and manage BFD sessions very effectively. Secondly,
	it is scalable when using unaffiliated BFD echo to adapt to different		it is scalable when using Unaffiliated BFD Echo to adapt to different
	capabilities of devices.		capabilities of devices.
	4. Security Considerations		5. Security Considerations
	Unicast Reverse Path Forwarding (uRPF), as specified in [RFC3704] and		Unicast Reverse Path Forwarding (uRPF), as specified in [RFC3704] and
	[RFC8704], is a security feature that prevents the IP address		[RFC8704], is a security feature that prevents the IP address
	spoofing attacks which is commonly used in DoS, DDoS. uRPF has two		spoofing attacks which is commonly used in DoS, DDoS. uRPF has two
	modes called strict mode and loose mode. uRPF strict mode means that		modes called strict mode and loose mode. uRPF strict mode means that
	the router will perform checks for all incoming packets on a certain		the router will perform checks for all incoming packets on a certain
	interface: whether the router has a matching entry for the source IP		interface: whether the router has a matching entry for the source IP
	in the routing table and whether the router uses the same interface		in the routing table and whether the router uses the same interface
	to reach this source IP as where the router received this packet on.		to reach this source IP as where the router received this packet on.
	Note that the use of BFD echo function would prevent the use of uRPF		Note that the use of BFD Echo function would prevent the use of uRPF
	in strict mode.		in strict mode.
	5. IANA Considerations		6. IANA Considerations
	This document has no IANA action requested.		This document has no IANA action requested.
	6. Acknowledgements		7. Acknowledgements
	TBD.		The authors would like to acknowledge Ketan Talaulikar, Greg Mirsky
			and Santosh Pallagatti for their careful review and very helpful
			comments.
	7. References		8. Contributors
	7.1. Normative References		Liu Aihua
			ZTE
			Email: liu.aihua@zte.com.cn
			Qian Xin
			ZTE
			Email: qian.xin2@zte.com.cn
			Zhao Yanhua
			ZTE
			Email: zhao.yanhua3@zte.com.cn
			9. References
			9.1. Normative References
	[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection		[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
	(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,		(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
	<https://www.rfc-editor.org/info/rfc5880>.		<https://www.rfc-editor.org/info/rfc5880>.
	[RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection		[RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
	(BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,		(BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
	DOI 10.17487/RFC5881, June 2010,		DOI 10.17487/RFC5881, June 2010,
	<https://www.rfc-editor.org/info/rfc5881>.		<https://www.rfc-editor.org/info/rfc5881>.
	7.2. Informative References		9.2. Informative References
	[BBF-TR-146]		[BBF-TR-146]
	Broadband Forum, "BBF Technical Report - Subscriber		Broadband Forum, "BBF Technical Report - Subscriber
	Sessions Issue 1", 2013, <https://www.broadband-		Sessions Issue 1", 2013, <https://www.broadband-
	forum.org/technical/download/TR-146.pdf>.		forum.org/technical/download/TR-146.pdf>.
	[RFC3704] Baker, F. and P. Savola, "Ingress Filtering for Multihomed		[RFC3704] Baker, F. and P. Savola, "Ingress Filtering for Multihomed
	Networks", BCP 84, RFC 3704, DOI 10.17487/RFC3704, March		Networks", BCP 84, RFC 3704, DOI 10.17487/RFC3704, March
	2004, <https://www.rfc-editor.org/info/rfc3704>.		2004, <https://www.rfc-editor.org/info/rfc3704>.
	skipping to change at page 6, line 4 ¶		skipping to change at page 9, line 34 ¶
	<https://www.rfc-editor.org/info/rfc8704>.		<https://www.rfc-editor.org/info/rfc8704>.
	Authors' Addresses		Authors' Addresses
	Weiqiang Cheng		Weiqiang Cheng
	China Mobile		China Mobile
	Beijing		Beijing
	CN		CN
	Email: chengweiqiang@chinamobile.com		Email: chengweiqiang@chinamobile.com
	Ruixue Wang		Ruixue Wang
	China Mobile		China Mobile
	Beijing		Beijing
	CN		CN
	Email: wangruixue@chinamobile.com		Email: wangruixue@chinamobile.com
	Xiao Min		Xiao Min
	ZTE Corp.		ZTE Corp.
	Nanjing		Nanjing
	CN		CN
	Email: xiao.min2@zte.com.cn		Email: xiao.min2@zte.com.cn
	Aihua Liu
	ZTE Corp.
	Shenzhen
	CN
	Email: liu.aihua@zte.com.cn
	Reshad Rahman		Reshad Rahman
	Cisco Systems		Cisco Systems
	Kanata		Kanata
	CA		CA
	Email: rrahman@cisco.com		Email: rrahman@cisco.com
	Raj Chetan Boddireddy		Raj Chetan Boddireddy
	Juniper Networks		Juniper Networks
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