< draft-ietf-lpwan-schc-over-lorawan-03.txt		draft-ietf-lpwan-schc-over-lorawan-04.txt >
	lpwan Working Group O. Gimenez, Ed.		lpwan Working Group O. Gimenez, Ed.
	Internet-Draft Semtech		Internet-Draft Semtech
	Intended status: Informational I. Petrov, Ed.		Intended status: Informational I. Petrov, Ed.
	Expires: April 11, 2020 Acklio		Expires: May 7, 2020 Acklio
	J. Catalano		November 04, 2019
	Kerlink
	October 09, 2019
	Static Context Header Compression (SCHC) over LoRaWAN		Static Context Header Compression (SCHC) over LoRaWAN
	draft-ietf-lpwan-schc-over-lorawan-03		draft-ietf-lpwan-schc-over-lorawan-04
	Abstract		Abstract
	The Static Context Header Compression (SCHC) specification describes		The Static Context Header Compression (SCHC) specification describes
	generic header compression and fragmentation techniques for LPWAN		generic header compression and fragmentation techniques for LPWAN
	(Low Power Wide Area Networks) technologies. SCHC is a generic		(Low Power Wide Area Networks) technologies. SCHC is a generic
	mechanism designed for great flexibility so that it can be adapted		mechanism designed for great flexibility so that it can be adapted
	for any of the LPWAN technologies.		for any of the LPWAN technologies.
	This document provides the adaptation of SCHC for use in LoRaWAN		This document provides the adaptation of SCHC for use in LoRaWAN
	skipping to change at page 1, line 41 ¶		skipping to change at page 1, line 39 ¶
	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 April 11, 2020.		This Internet-Draft will expire on May 7, 2020.
	Copyright Notice		Copyright Notice
	Copyright (c) 2019 IETF Trust and the persons identified as the		Copyright (c) 2019 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
	skipping to change at page 2, line 22 ¶		skipping to change at page 2, line 20 ¶
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
	2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3		2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
	3. Static Context Header Compression Overview . . . . . . . . . 3		3. Static Context Header Compression Overview . . . . . . . . . 3
	4. LoRaWAN Architecture . . . . . . . . . . . . . . . . . . . . 5		4. LoRaWAN Architecture . . . . . . . . . . . . . . . . . . . . 5
	4.1. End-Device classes (A, B, C) and interactions . . . . . . 6		4.1. End-Device classes (A, B, C) and interactions . . . . . . 6
	4.2. End-Device addressing . . . . . . . . . . . . . . . . . . 7		4.2. End-Device addressing . . . . . . . . . . . . . . . . . . 7
	4.3. General Message Types . . . . . . . . . . . . . . . . . . 7		4.3. General Message Types . . . . . . . . . . . . . . . . . . 7
	4.4. LoRaWAN MAC Frames . . . . . . . . . . . . . . . . . . . 8		4.4. LoRaWAN MAC Frames . . . . . . . . . . . . . . . . . . . 8
			4.5. Unicast and multicast technology . . . . . . . . . . . . 8
	5. SCHC-over-LoRaWAN . . . . . . . . . . . . . . . . . . . . . . 8		5. SCHC-over-LoRaWAN . . . . . . . . . . . . . . . . . . . . . . 8
	5.1. LoRaWAN FPort . . . . . . . . . . . . . . . . . . . . . . 8		5.1. LoRaWAN FPort . . . . . . . . . . . . . . . . . . . . . . 8
	5.2. Rule ID management . . . . . . . . . . . . . . . . . . . 9		5.2. Rule ID management . . . . . . . . . . . . . . . . . . . 9
	5.3. IID computation . . . . . . . . . . . . . . . . . . . . . 9		5.3. IID computation . . . . . . . . . . . . . . . . . . . . . 10
	5.4. Padding . . . . . . . . . . . . . . . . . . . . . . . . . 10		5.4. Padding . . . . . . . . . . . . . . . . . . . . . . . . . 10
	5.5. Compression . . . . . . . . . . . . . . . . . . . . . . . 10		5.5. Compression . . . . . . . . . . . . . . . . . . . . . . . 10
	5.6. Fragmentation . . . . . . . . . . . . . . . . . . . . . . 10		5.6. Fragmentation . . . . . . . . . . . . . . . . . . . . . . 10
	5.6.1. DTag . . . . . . . . . . . . . . . . . . . . . . . . 10		5.6.1. DTag . . . . . . . . . . . . . . . . . . . . . . . . 11
	5.6.2. Uplink fragmentation: From device to SCHC gateway . . 10		5.6.2. Uplink fragmentation: From device to SCHC gateway . . 11
	5.6.3. Downlink fragmentation: From SCHC gateway to a device 13		5.6.3. Downlink fragmentation: From SCHC gateway to a device 13
	6. Security considerations . . . . . . . . . . . . . . . . . . . 16		6. Security considerations . . . . . . . . . . . . . . . . . . . 17
	Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 17		Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 17
	Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 17		Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 17
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . 17		9. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
	9.1. Normative References . . . . . . . . . . . . . . . . . . 17		9.1. Normative References . . . . . . . . . . . . . . . . . . 18
	9.2. Informative References . . . . . . . . . . . . . . . . . 18		9.2. Informative References . . . . . . . . . . . . . . . . . 19
	Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 18		Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 19
	A.1. Uplink - Compression example - No fragmentation . . . . . 18		A.1. Uplink - Compression example - No fragmentation . . . . . 19
	A.2. Uplink - Compression and fragmentation example . . . . . 19		A.2. Uplink - Compression and fragmentation example . . . . . 20
	A.3. Downlink . . . . . . . . . . . . . . . . . . . . . . . . 20		A.3. Downlink . . . . . . . . . . . . . . . . . . . . . . . . 22
	Appendix B. Note . . . . . . . . . . . . . . . . . . . . . . . . 22		Appendix B. Note . . . . . . . . . . . . . . . . . . . . . . . . 23
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23
	1. Introduction		1. Introduction
	The Static Context Header Compression (SCHC) specification		The Static Context Header Compression (SCHC) specification
	[I-D.ietf-lpwan-ipv6-static-context-hc] describes generic header		[I-D.ietf-lpwan-ipv6-static-context-hc] describes generic header
	compression and fragmentation techniques that can be used on all		compression and fragmentation techniques that can be used on all
	LPWAN (Low Power Wide Area Networks) technologies defined in		LPWAN (Low Power Wide Area Networks) technologies defined in
	[RFC8376]. Even though those technologies share a great number of		[RFC8376]. Even though those technologies share a great number of
	common features like star-oriented topologies, network architecture,		common features like star-oriented topologies, network architecture,
	devices with mostly quite predictable communications, etc; they do		devices with mostly quite predictable communications, etc; they do
	skipping to change at page 8, line 19 ¶		skipping to change at page 8, line 19 ¶
	and a random nonce that will be used for session key derivation.		and a random nonce that will be used for session key derivation.
	o JoinAccept: To on-board an end-device, the Network Server responds		o JoinAccept: To on-board an end-device, the Network Server responds
	to the JoinRequest end-device's message with a JoinAccept message.		to the JoinRequest end-device's message with a JoinAccept message.
	That message is encrypted with the end-device's AppKey and		That message is encrypted with the end-device's AppKey and
	contains (amongst other fields) the major network's settings and a		contains (amongst other fields) the major network's settings and a
	network random nonce used to derive the session keys.		network random nonce used to derive the session keys.
	o Data		o Data
			4.5. Unicast and multicast technology
			LoRaWAN technology supports unicast downlinks, but also multicast: a
			packet send over LoRaWAN radio link can be received by several
			devices. It is useful to address many end-devices with same content,
			either a large binary file (firmware upgrade), or same command (e.g:
			lighting control). As IPv6 is also a multicast technology this
			feature MAY be used to address a group of devices.
			_Note 1_: IPv6 multicast addresses must be defined as per [RFC4291].
			LoRaWAN multicast group definition in a network server and the
			relation between those groups and IPv6 groupID are out of scope of
			this document.
			_Note 2_: LoRa Alliance defined [lora-alliance-remote-multicast-set]
			as RECOMMENDED way to setup multicast groups on devices and create a
			synchronized reception window.
	5. SCHC-over-LoRaWAN		5. SCHC-over-LoRaWAN
	5.1. LoRaWAN FPort		5.1. LoRaWAN FPort
	The LoRaWAN MAC layer features a frame port field in all frames.		The LoRaWAN MAC layer features a frame port field in all frames.
	This field (FPort) is 8-bit long and the values from 1 to 223 can be		This field (FPort) is 8 bits long and the values from 1 to 223 can be
	used. It allows LoRaWAN networks and applications to identify data.		used. It allows LoRaWAN networks and applications to identify data.
	The FPort field is part of the SCHC Packet or the SCHC Fragment, as		The FPort field is part of the SCHC Packet or the SCHC Fragment, as
	shown in Figure 5. The SCHC C/D and the SCHC F/R SHALL concatenate		shown in Figure 5. The SCHC C/D and the SCHC F/R SHALL concatenate
	the FPort field with the LoRaWAN payload to retrieve their payload as		the FPort field with the LoRaWAN payload to retrieve their payload as
	it is used as a part of the ruleId field.		it is used as a part of the ruleId field.
	| FPort | LoRaWAN payload |		| FPort | LoRaWAN payload |
	+ ------------------------ +		+ ------------------------ +
	| SCHC payload |		| SCHC payload |
	skipping to change at page 9, line 7 ¶		skipping to change at page 9, line 27 ¶
	data downlink and its associated SCHC control uplinks, named		data downlink and its associated SCHC control uplinks, named
	FPortDown in this document.		FPortDown in this document.
	FPorts can use arbitrary values inside the allowed FPort range and		FPorts can use arbitrary values inside the allowed FPort range and
	MUST be shared by the end-device, the Network Server and SCHC gateway		MUST be shared by the end-device, the Network Server and SCHC gateway
	prior to the communication. The uplink and downlink fragmentation		prior to the communication. The uplink and downlink fragmentation
	FPorts MUST be different.		FPorts MUST be different.
	5.2. Rule ID management		5.2. Rule ID management
	RuleID minimum length MUST be 8 bits, and RECOMMENDED length is 8		RuleID MUST be 8 bits, encoded in the LoRaWAN FPort as described in
	bits. RuleID MSB is encoded in the LoRaWAN FPort as described in
	Section 5.1. LoRaWAN supports up to 223 application FPorts in the		Section 5.1. LoRaWAN supports up to 223 application FPorts in the
	range [1;223] as defined in section 4.3.2 of [lora-alliance-spec], it		range [1;223] as defined in section 4.3.2 of [lora-alliance-spec], it
	implies that RuleID MSB SHOULD be inside this range. An application		implies that RuleID MSB SHOULD be inside this range. An application
	MAY reserve some FPort values for other needs as long as they don't		MAY reserve some FPort values for other needs as long as they don't
	conflict with FPorts used for SCHC C/D and SCHC F/R.		conflict with FPorts used for SCHC C/D and SCHC F/R.
	A RuleID SHOULD be reserved to tag packets for which SCHC compression		In order to improve interoperability RECOMMENDED fragmentation RuleID
	was not possible (no matching Rule was found). RuleIDs FPortUp and		values are:
	FPortDown are reserved for fragmentation, in order to improve
	interoperability RECOMMENDED values are:
	o RuleID = 20 (8-bit) for uplink fragmentation, named FPortUp		o RuleID = 20 (8-bit) for uplink fragmentation, named FPortUp
	o RuleID = 21 (8-bit) for downlink fragmentation, named FPortDown		o RuleID = 21 (8-bit) for downlink fragmentation, named FPortDown
	o RuleID = 22 (8-bit) for which SCHC compression was not possible		o RuleID = 22 (8-bit) for which SCHC compression was not possible
			(no matching rule was found)
	The remaining RuleIDs are available for compression. RuleIDs are		The remaining RuleIDs are available for compression. RuleIDs are
	shared between uplink and downlink sessions. A RuleID different from		shared between uplink and downlink sessions. A RuleID different from
	FPortUp or FPortDown means that the fragmentation is not used, thus		FPortUp or FPortDown means that the fragmentation is not used, thus
	the packet SHOULD be sent to C/D layer.		the packet SHOULD be sent to C/D layer.
	The only uplink messages using the FPortDown port are the		The only uplink messages using the FPortDown port are the
	fragmentation SCHC control messages of a downlink fragmentation		fragmentation SCHC control messages of a downlink fragmentation
	session (ex ACKs). Similarly, the only downlink messages using the		session (ex ACKs). Similarly, the only downlink messages using the
	FPortUp port are the fragmentation SCHC control messages of an uplink		FPortUp port are the fragmentation SCHC control messages of an uplink
	skipping to change at page 10, line 14 ¶		skipping to change at page 10, line 33 ¶
	5.4. Padding		5.4. Padding
	All padding bits MUST be 0.		All padding bits MUST be 0.
	5.5. Compression		5.5. Compression
	SCHC C/D MUST concatenate FPort and LoRaWAN payload to retrieve the		SCHC C/D MUST concatenate FPort and LoRaWAN payload to retrieve the
	SCHC packet as per Section 5.1.		SCHC packet as per Section 5.1.
	SCHC C/D RuleID size SHOULD be 8 bits to fit the LoRaWAN FPort field.
	RuleIDs matching FPortUp and FPortDown are reserved for SCHC		RuleIDs matching FPortUp and FPortDown are reserved for SCHC
	Fragmentation.		Fragmentation.
	5.6. Fragmentation		5.6. Fragmentation
	The L2 word size used by LoRaWAN is 1 byte (8 bits). The SCHC		The L2 word size used by LoRaWAN is 1 byte (8 bits). The SCHC
	fragmentation over LoRaWAN uses the ACK-on-Error for uplink		fragmentation over LoRaWAN uses the ACK-on-Error for uplink
	fragmentation and Ack-Always for downlink fragmentation. A LoRaWAN		fragmentation and Ack-Always for downlink fragmentation. A LoRaWAN
	end-device cannot support simultaneous interleaved fragmentation		end-device cannot support simultaneous interleaved fragmentation
	sessions in the same direction (uplink or downlink). This means that		sessions in the same direction (uplink or downlink). This means that
	skipping to change at page 10, line 48 ¶		skipping to change at page 11, line 21 ¶
	sessions with one or more SCHC gateway(s) thanks to distinct sets of		sessions with one or more SCHC gateway(s) thanks to distinct sets of
	FPorts, cf Section 5.2		FPorts, cf Section 5.2
	5.6.2. Uplink fragmentation: From device to SCHC gateway		5.6.2. Uplink fragmentation: From device to SCHC gateway
	In that case the device is the fragmentation transmitter, and the		In that case the device is the fragmentation transmitter, and the
	SCHC gateway the fragmentation receiver. A single fragmentation rule		SCHC gateway the fragmentation receiver. A single fragmentation rule
	is defined. SCHC F/R MUST concatenate FPort and LoRaWAN payload to		is defined. SCHC F/R MUST concatenate FPort and LoRaWAN payload to
	retrieve the SCHC fragment as per Section 5.1.		retrieve the SCHC fragment as per Section 5.1.
	o Minimum SCHC header is two bytes (the FPort byte + 1 additional		o SCHC header size is two bytes (the FPort byte + 1 additional
	byte) and the RECOMMENDED header size is two bytes.		byte).
	o RuleID: Recommended size is 8 bits in SCHC header.		o RuleID: 8 bits stored in LoRaWAN FPort.
	o SCHC fragmentation reliability mode: "ACK-on-Error"		o SCHC fragmentation reliability mode: "ACK-on-Error"
	o DTag: Size is 0 bit, not used		o DTag: Size is 0 bit, not used
	o FCN: The FCN field is encoded on N = 6 bits, so WINDOW_SIZE = 64		o FCN: The FCN field is encoded on N = 6 bits, so WINDOW_SIZE = 63
	tiles are allowed in a window		tiles are allowed in a window
	o Window index: encoded on W = 2 bits. So 4 windows are available.		o Window index: encoded on W = 2 bits. So 4 windows are available.
	o RCS calculation algorithm: CRC32 using 0xEDB88320 (i.e. the		o RCS calculation algorithm: CRC32 using 0xEDB88320 (i.e. the
	reverse representation of the polynomial used e.g. in the Ethernet		reverse representation of the polynomial used e.g. in the Ethernet
	standard [RFC3385]) as suggested in		standard [RFC3385]) as suggested in
	[I-D.ietf-lpwan-ipv6-static-context-hc].		[I-D.ietf-lpwan-ipv6-static-context-hc].
	o MAX_ACK_REQUESTS: 8		o MAX_ACK_REQUESTS: 8
	o Tile: size is 5 bytes		o Tile: size is 10 bytes
	o Retransmission and inactivity timers: LoRaWAN end-devices do not		o Retransmission and inactivity timers: LoRaWAN end-devices do not
	implement a "retransmission timer". At the end of a window or a		implement a "retransmission timer". At the end of a window or a
	fragmentation session, corresponding ACK(s) is (are) transmitted		fragmentation session, corresponding ACK(s) is (are) transmitted
	by the network gateway (LoRaWAN application server) in the RX1 or		by the network gateway (LoRaWAN application server) in the RX1 or
	RX2 receive slot of end-device. If this ACK is not received by		RX2 receive slot of end-device. If this ACK is not received by
	the end-device at the end of its RX windows, it sends an all-0 (or		the end-device at the end of its RX windows, it sends an all-0 (or
	an all-1) fragment with no payload to request an SCHC ACK		an all-1) fragment with no payload to request an SCHC ACK
	retransmission. The periodicity between retransmission of the		retransmission. The periodicity between retransmission of the
	all-0/all-1 fragments is device/application specific and MAY be		all-0/all-1 fragments is device/application specific and MAY be
	different for each device (not specified). The SCHC gateway		different for each device (not specified). The SCHC gateway
	implements an "inactivity timer". The default RECOMMENDED		implements an "inactivity timer". The default RECOMMENDED
	duration of this timer is 12 hours. This value is mainly driven		duration of this timer is 12 hours. This value is mainly driven
	by application requirements and MAY be changed by the application.		by application requirements and MAY be changed by the application.
	o Last tile: The last tile can be carried in the All-1 fragment.		o Last tile: The last tile can be carried in the All-1 fragment.
	With this set of parameters, the SCHC fragment header is 16 bits,		With this set of parameters, the SCHC fragment header is 16 bits,
	including FPort; payload overhead will be 8 bits as FPort is already		including FPort; payload overhead will be 8 bits as FPort is already
	a part of LoRaWAN payload. MTU is: _4 windows * 64 tiles * 5 bytes		a part of LoRaWAN payload. MTU is: _4 windows * 63 tiles * 10 bytes
	per tile = 1280 bytes_		per tile = 2520 bytes_
	5.6.2.1. Regular fragments		5.6.2.1. Regular fragments
	| FPort | LoRaWAN payload |		| FPort | LoRaWAN payload |
	+ ------ + ------------------------- +		+ ------ + ------------------------- +
	| RuleID | W | FCN | Payload |		| RuleID | W | FCN | Payload |
	+ ------ + ------ + ------ + ------- +		+ ------ + ------ + ------ + ------- +
	| 8 bits | 2 bits | 6 bits | |		| 8 bits | 2 bits | 6 bits | |
	Figure 6: All fragments except the last one. SCHC header size is 16		Figure 6: All fragments except the last one. SCHC header size is 16
	bits, including LoRaWAN FPort.		bits, including LoRaWAN FPort.
	5.6.2.2. Last fragment (All-1)		5.6.2.2. Last fragment (All-1)
	skipping to change at page 13, line 22 ¶		skipping to change at page 13, line 33 ¶
	Figure 10: SCHC ACK REQ format.		Figure 10: SCHC ACK REQ format.
	5.6.3. Downlink fragmentation: From SCHC gateway to a device		5.6.3. Downlink fragmentation: From SCHC gateway to a device
	In that case the device is the fragmentation receiver, and the SCHC		In that case the device is the fragmentation receiver, and the SCHC
	gateway the fragmentation transmitter. The following fields are		gateway the fragmentation transmitter. The following fields are
	common to all devices. SCHC F/R MUST concatenate FPort and LoRaWAN		common to all devices. SCHC F/R MUST concatenate FPort and LoRaWAN
	payload to retrieve the SCHC fragment as described in Section 5.1.		payload to retrieve the SCHC fragment as described in Section 5.1.
	o SCHC fragmentation reliability mode: ACK-Always.		o SCHC fragmentation reliability mode:
	o RuleID: Recommended size is 8 bits in SCHC header.		* Unicast downlinks: ACK-Always.
	o Window index: encoded on W=1 bit, as per		* Multicast downlinks: No-ACK, reliability has be be ensured by
			the upper layer. This feature is OPTIONAL and may not be
			implemented by SCHC gateway.
			o RuleID: 8 bits stored in LoRaWAN FPort.
			o Window index (unicast only): encoded on W=1 bit, as per
	[I-D.ietf-lpwan-ipv6-static-context-hc].		[I-D.ietf-lpwan-ipv6-static-context-hc].
	o DTag: Size is 0 bit, not used		o DTag: Size is 0 bit, not used
	o FCN: The FCN field is encoded on N=1 bit, so WINDOW_SIZE = 1 tile		o FCN: The FCN field is encoded on N=1 bit, so WINDOW_SIZE = 1 tile
	(FCN=All-1 is reserved for SCHC).		(FCN=All-1 is reserved for SCHC).
	o RCS calculation algorithm: CRC32 using 0xEDB88320 (i.e. the		o RCS calculation algorithm: CRC32 using 0xEDB88320 (i.e. the
	reverse representation of the polynomial used e.g. in the Ethernet		reverse representation of the polynomial used e.g. in the Ethernet
	standard [RFC3385]), as per		standard [RFC3385]), as per
	skipping to change at page 17, line 20 ¶		skipping to change at page 17, line 35 ¶
	excellent text, insightful discussions, reviews and suggestions.		excellent text, insightful discussions, reviews and suggestions.
	Contributors		Contributors
	Contributors ordered by family name.		Contributors ordered by family name.
	o ins: V. Audebert name: Vincent AUDEBERT org: EDF R&D street: 7 bd		o ins: V. Audebert name: Vincent AUDEBERT org: EDF R&D street: 7 bd
	Gaspard Monge city: 91120 PALAISEAU country: FRANCE email:		Gaspard Monge city: 91120 PALAISEAU country: FRANCE email:
	vincent.audebert@edf.fr		vincent.audebert@edf.fr
			o ins: J. Catalano name: Julien Catalano org: Kerlink street: 1 rue
			Jacqueline Auriol city: 35235 Thorigne-Fouillard country: France
			email: j.catalano@kerlink.fr
	o ins: M. Coracin name: Michael Coracin org: Semtech street: 14		o ins: M. Coracin name: Michael Coracin org: Semtech street: 14
	Chemin des Clos city: Meylan country: France email:		Chemin des Clos city: Meylan country: France email:
	mcoracin@semtech.com		mcoracin@semtech.com
	o ins: M. Le Gourrierec name: Marc Le Gourrierec org: SagemCom		o ins: M. Le Gourrierec name: Marc Le Gourrierec org: SagemCom
	street: 250 Route de l'Empereur city: 92500 Rueil Malmaison		street: 250 Route de l'Empereur city: 92500 Rueil Malmaison
	country: FRANCE email: marc.legourrierec@sagemcom.com		country: FRANCE email: marc.legourrierec@sagemcom.com
	o ins: N. Sornin name: Nicolas Sornin org: Semtech street: 14		o ins: N. Sornin name: Nicolas Sornin org: Semtech street: 14
	Chemin des Clos city: Meylan country: France email:		Chemin des Clos city: Meylan country: France email:
	skipping to change at page 18, line 37 ¶		skipping to change at page 19, line 11 ¶
	[RFC8376] Farrell, S., Ed., "Low-Power Wide Area Network (LPWAN)		[RFC8376] Farrell, S., Ed., "Low-Power Wide Area Network (LPWAN)
	Overview", RFC 8376, DOI 10.17487/RFC8376, May 2018,		Overview", RFC 8376, DOI 10.17487/RFC8376, May 2018,
	<https://www.rfc-editor.org/info/rfc8376>.		<https://www.rfc-editor.org/info/rfc8376>.
	9.2. Informative References		9.2. Informative References
	[I-D.ietf-lpwan-ipv6-static-context-hc]		[I-D.ietf-lpwan-ipv6-static-context-hc]
	Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and J.		Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and J.
	Zuniga, "Static Context Header Compression (SCHC) and		Zuniga, "Static Context Header Compression (SCHC) and
	fragmentation for LPWAN, application to UDP/IPv6", draft-		fragmentation for LPWAN, application to UDP/IPv6", draft-
	ietf-lpwan-ipv6-static-context-hc-21 (work in progress),		ietf-lpwan-ipv6-static-context-hc-22 (work in progress),
	July 2019.		October 2019.
			[lora-alliance-remote-multicast-set]
			Alliance, L., "LoRaWAN Remote Multicast Setup
			Specification Version 1.0.0", <https://lora-
			alliance.org/sites/default/files/2018-09/
			remote_multicast_setup_v1.0.0.pdf>.
	[lora-alliance-spec]		[lora-alliance-spec]
	Alliance, L., "LoRaWAN Specification Version V1.0.3",		Alliance, L., "LoRaWAN Specification Version V1.0.3",
	<https://lora-alliance.org/sites/default/files/2018-07/		<https://lora-alliance.org/sites/default/files/2018-07/
	lorawan1.0.3.pdf>.		lorawan1.0.3.pdf>.
	Appendix A. Examples		Appendix A. Examples
	A.1. Uplink - Compression example - No fragmentation		A.1. Uplink - Compression example - No fragmentation
	skipping to change at page 19, line 39 ¶		skipping to change at page 20, line 39 ¶
	with fragmentation.		with fragmentation.
	An applicative payload of 478 bytes is passed to SCHC compression layer		An applicative payload of 478 bytes is passed to SCHC compression layer
	using rule 1, allowing to compress it to 282 bytes and 5 bits: 1 byte		using rule 1, allowing to compress it to 282 bytes and 5 bits: 1 byte
	ruleID, 21 bits residue + 279 bytes payload.		ruleID, 21 bits residue + 279 bytes payload.
	| RuleID | Compression residue | Payload |		| RuleID | Compression residue | Payload |
	+ ------ + ------------------- + --------- +		+ ------ + ------------------- + --------- +
	| 1 | 21 bits | 279 bytes |		| 1 | 21 bits | 279 bytes |
	The current LoRaWAN MTU is 11 bytes, although 2 bytes FOpts are used by		The current LoRaWAN MTU is 11 bytes, 0 bytes FOpts are used by LoRaWAN
	LoRaWAN protocol: 9 bytes are available for SCHC payload + 1 byte FPort		protocol: 11 bytes are available for SCHC payload + 1 byte FPort field.
	field. SCHC header is 2 bytes (including FPort) so 1 tile is sent in		SCHC header is 2 bytes (including FPort) so 1 tile is sent in first
	first fragment.		fragment.
	| LoRaWAN Header | LoRaWAN payload (6 bytes) |		| LoRaWAN Header | LoRaWAN payload (11 bytes) |
	+ ------------------------------------- + ------------------------- +		+ -------------------------- + -------------------------- +
	| | FOpts | RuleID=20 | W | FCN | 1 tile |		| | RuleID=20 | W | FCN | 1 tile |
	+ -------------- + ------- + ---------- + ----- + ------ + -------- +		+ -------------- + --------- + ----- + ------ + --------- +
	| XXXX | 2 bytes | 1 byte | 0 0 | 62 | 5 bytes |		| XXXX | 1 byte | 0 0 | 62 | 10 bytes |
	Content of the tile is:		Content of the tile is:
	| RuleID | Compression residue | Payload |		| RuleID | Compression residue | Payload |
	+ ------ + ------------------- + ----------------- +		+ ------ + ------------------- + ----------------- +
	| 1 | 21 bits | 1 byte + 3 bits |		| 1 | 21 bits | 6 byte + 3 bits |
	Next transmission MTU is 242 bytes, no FOpts. 48 tiles are transmitted:		Next transmission MTU is 11 bytes, although 2 bytes FOpts are used by
			LoRaWAN protocol: 9 bytes are available for SCHC payload + 1 byte FPort
			field, a tile does not fit inside so LoRaWAN stack will send only FOpts.
	| LoRaWAN Header | LoRaWAN payload (241 bytes) |		Next transmission MTU is 242 bytes, 4 bytes FOpts. 23 tiles are transmitted:
	+ -------------- + -----------+ --------------------------- +
	| | RuleID=20 | W | FCN | 48 tiles |
	+ -------------- + ---------- + ----- + ------ + ---------- +
	| XXXX | 1 byte | 0 0 | 61 | 240 bytes |
	Next transmission MTU is 242 bytes, no FOpts. All 8 remaining tiles are		| LoRaWAN Header | LoRaWAN payload (231 bytes) |
			+ --------------------------------------+ --------------------------- +
			| | FOpts | RuleID=20 | W | FCN | 23 tiles |
			+ -------------- + ------- + ---------- + ----- + ----- + ----------- +
			| XXXX | 4 bytes | 1 byte | 0 0 | 61 | 230 bytes |
			Next transmission MTU is 242 bytes, no FOpts. All 5 remaining tiles are
	transmitted, the last tile is only 2 bytes + 5 bits. Padding is added for		transmitted, the last tile is only 2 bytes + 5 bits. Padding is added for
	the remaining 3 bits.		the remaining 3 bits.
	| LoRaWAN Header | LoRaWAN payload (39 bytes) |		| LoRaWAN Header | LoRaWAN payload (44 bytes) |
	+ ---- + -----------+ ----------------------------------------------- +		+ ---- + -----------+ ----------------------------------------------- +
	| | RuleID=20 | W | FCN | 8 tiles | Padding=b'000 |		| | RuleID=20 | W | FCN | 5 tiles | Padding=b'000 |
	+ ---- + ---------- + -- + ------ + ----------------- + ------------- +		+ ---- + ---------- + ----- + ----- + ----------------- + ------------- +
	| XXXX | 1 byte | 00 | 13 | 37 bytes + 5 bits | 3 bits |		| XXXX | 1 byte | 0 0 | 38 | 42 bytes + 5 bits | 3 bits |
	All packets have been received by the SCHC gateway, computed RCS is		All packets have been received by the SCHC gateway, computed RCS is
	correct so the following ACK is sent to the device:		correct so the following ACK is sent to the device:
	| LoRaWAN Header | LoRaWAN payload |		| LoRaWAN Header | LoRaWAN payload |
	+ -------------- + --------- + ------------------- +		+ -------------- + --------- + ------------------- +
	| | RuleID=20 | W | C | Padding |		| | RuleID=20 | W | C | Padding |
	+ -------------- + --------- + ----- + - + ------- +		+ -------------- + --------- + ----- + - + ------- +
	| XXXX | 1 byte | 0 0 | 1 | 5 bits |		| XXXX | 1 byte | 0 0 | 1 | 5 bits |
	skipping to change at page 22, line 33 ¶		skipping to change at page 24, line 4 ¶
	Authors' Addresses		Authors' Addresses
	Olivier Gimenez (editor)		Olivier Gimenez (editor)
	Semtech		Semtech
	14 Chemin des Clos		14 Chemin des Clos
	Meylan		Meylan
	France		France
	Email: ogimenez@semtech.com		Email: ogimenez@semtech.com
	Ivaylo Petrov (editor)		Ivaylo Petrov (editor)
	Acklio		Acklio
	1137A Avenue des Champs Blancs		1137A Avenue des Champs Blancs
	35510 Cesson-Sevigne Cedex		35510 Cesson-Sevigne Cedex
	France		France
	Email: ivaylo@ackl.io		Email: ivaylo@ackl.io
	Julien Catalano
	Kerlink
	1 rue Jacqueline Auriol
	35235 Thorigne-Fouillard
	France
	Email: j.catalano@kerlink.fr
End of changes. 35 change blocks.
	61 lines changed or deleted		95 lines changed or added
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