draft-ietf-6lo-routing-dispatch-02.txt   draft-ietf-6lo-routing-dispatch-03.txt 
6lo P. Thubert, Ed. 6lo P. Thubert, Ed.
Internet-Draft Cisco Internet-Draft Cisco
Intended status: Standards Track C. Bormann Intended status: Standards Track C. Bormann
Expires: July 17, 2016 Uni Bremen TZI Expires: July 18, 2016 Uni Bremen TZI
L. Toutain L. Toutain
IMT-TELECOM Bretagne IMT-TELECOM Bretagne
R. Cragie R. Cragie
ARM ARM
January 14, 2016 January 15, 2016
6LoWPAN Routing Header And Paging Dispatches 6LoWPAN Routing Header And Paging Dispatches
draft-ietf-6lo-routing-dispatch-02 draft-ietf-6lo-routing-dispatch-03
Abstract Abstract
This specification introduces a new 6LoWPAN dispatch type for use in This specification introduces a new 6LoWPAN dispatch type for use in
6LoWPAN Route-Over topologies, that initially covers the needs of RPL 6LoWPAN Route-Over topologies, that initially covers the needs of RPL
(RFC6550) data packets compression. Using this dispatch type, this (RFC6550) data packets compression. Using this dispatch type, this
specification defines a method to compress RPL Option (RFC6553) specification defines a method to compress RPL Option (RFC6553)
information and Routing Header type 3 (RFC6554), an efficient IP-in- information and Routing Header type 3 (RFC6554), an efficient IP-in-
IP technique and is extensible for more applications. IP technique and is extensible for more applications.
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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-
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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 July 17, 2016. This Internet-Draft will expire on July 18, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 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
(http://trustee.ietf.org/license-info) in effect on the date of (http://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 1, line 67 skipping to change at page 1, line 67
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Using the Page Dispatch . . . . . . . . . . . . . . . . . . . 5 3. Using the Page Dispatch . . . . . . . . . . . . . . . . . . . 5
3.1. New Routing Header Dispatch (6LoRH) . . . . . . . . . . . 6 3.1. New Routing Header Dispatch (6LoRH) . . . . . . . . . . . 6
3.2. Placement Of The 6LoRH . . . . . . . . . . . . . . . . . 6 3.2. Placement Of The 6LoRH . . . . . . . . . . . . . . . . . 6
4. 6LoWPAN Routing Header General Format . . . . . . . . . . . . 6 4. 6LoWPAN Routing Header General Format . . . . . . . . . . . . 6
4.1. Elective Format . . . . . . . . . . . . . . . . . . . . . 7 4.1. Elective Format . . . . . . . . . . . . . . . . . . . . . 7
4.2. Critical Format . . . . . . . . . . . . . . . . . . . . . 7 4.2. Critical Format . . . . . . . . . . . . . . . . . . . . . 7
5. The Routing Header Type 3 (RH3) 6LoRH . . . . . . . . . . . . 8 5. The Routing Header Type 3 (RH3) 6LoRH Header . . . . . . . . 8
6. The RPL Packet Information 6LoRH . . . . . . . . . . . . . . 10 6. The RPL Packet Information 6LoRH . . . . . . . . . . . . . . 10
6.1. Compressing the RPLInstanceID . . . . . . . . . . . . . . 11 6.1. Compressing the RPLInstanceID . . . . . . . . . . . . . . 11
6.2. Compressing the SenderRank . . . . . . . . . . . . . . . 11 6.2. Compressing the SenderRank . . . . . . . . . . . . . . . 11
6.3. The Overall RPI-6LoRH encoding . . . . . . . . . . . . . 12 6.3. The Overall RPI-6LoRH encoding . . . . . . . . . . . . . 12
7. The IP-in-IP 6LoRH . . . . . . . . . . . . . . . . . . . . . 14 7. The IP-in-IP 6LoRH Header . . . . . . . . . . . . . . . . . . 14
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15 8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
9.1. Reserving Space in 6LoWPAN Dispatch Page 1 . . . . . . . 15 9.1. Reserving Space in 6LoWPAN Dispatch Page 1 . . . . . . . 15
9.2. Nex 6LoWPAN Routing Header Type Registry . . . . . . . . 15 9.2. Nex 6LoWPAN Routing Header Type Registry . . . . . . . . 16
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16 10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
11.1. Normative References . . . . . . . . . . . . . . . . . . 16 11.1. Normative References . . . . . . . . . . . . . . . . . . 16
11.2. Informative References . . . . . . . . . . . . . . . . . 17 11.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 18 Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction 1. Introduction
The design of Low Power and Lossy Networks (LLNs) is generally The design of Low Power and Lossy Networks (LLNs) is generally
skipping to change at page 1, line 125 skipping to change at page 1, line 125
the case when the additional routing information is inserted by a the case when the additional routing information is inserted by a
router on the path of a packet, for instance a mesh root, as opposed router on the path of a packet, for instance a mesh root, as opposed
to the source node. This is also the case when some routing to the source node. This is also the case when some routing
information must be removed from a packet that flows outside the LLN. information must be removed from a packet that flows outside the LLN.
When to use RFC 6553, 6554 and IPv6-in-IPv6 When to use RFC 6553, 6554 and IPv6-in-IPv6
[I-D.robles-roll-useofrplinfo] details different cases where RFC [I-D.robles-roll-useofrplinfo] details different cases where RFC
6553, RFC 6554 and IPv6-in-IPv6 encapsulation is required to set the 6553, RFC 6554 and IPv6-in-IPv6 encapsulation is required to set the
bases to help defining the compression of RPL routing information in bases to help defining the compression of RPL routing information in
LLN environments. LLN environments.
When using [RFC6282] the outter IP header of an IP-in-IP When using [RFC6282] the outer IP header of an IP-in-IP encapsulation
encapsulation may be compressed down to 2 octets in stateless may be compressed down to 2 octets in stateless compression and down
compression and down to 3 octets in case of a stateful compression to 3 octets in stateful compression when context information must be
when a context information must be added. added.
0 1 0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
| 0 | 1 | 1 | TF |NH | HLIM |CID|SAC| SAM | M |DAC| DAM | | 0 | 1 | 1 | TF |NH | HLIM |CID|SAC| SAM | M |DAC| DAM |
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
Figure 1: LOWPAN_IPHC base Encoding (RFC6282). Figure 1: LOWPAN_IPHC base Encoding (RFC6282).
The Stateless Compression of an IPv6 addresses can only happen if the The Stateless Compression of an IPv6 addresses can only happen if the
IPv6 address can de deduced from the MAC addresses, meaning that the IPv6 address can de deduced from the MAC addresses, meaning that the
IP end point is also the MAC-layer endpoint. This is generally not IP end point is also the MAC-layer endpoint. This is generally not
the case in a RPL network which is generally a multi-hop route-over the case in a RPL network which is generally a multi-hop route-over
(operated at Layer-3) network. A better compression, that does not (i.e., operated at Layer-3) network. A better compression, which
involve variable compressions depending on the hop in the mesh, can does not involve variable compressions depending on the hop in the
be achieved based on the fact that the outter encapsulation is mesh, can be achieved based on the fact that the outer encapsulation
usually between the source (or destination) of the inner packet and is usually between the source (or destination) of the inner packet
the root. Also, the inner IP header can only be compressed by and the root. Also, the inner IP header can only be compressed by
[RFC6282] if all the fields up to it are also compressed. This [RFC6282] if all the fields preceding it are also compressed. This
specification makes it so that the inner IP header is the first specification makes the inner IP header the first header to be
header that is compressed by [RFC6282], and conserves the inner compressed by [RFC6282], and keeps the inner packet encoded the same
packet encoded the same way whether it is encapsulated or not, way whether it is encapsulated or not, thus preserving existing
conserving existing implementation. implementations.
As an example, the Routing Protocol for Low Power and Lossy Networks As an example, the Routing Protocol for Low Power and Lossy Networks
[RFC6550] (RPL) is designed to optimize the routing operations in [RFC6550] (RPL) is designed to optimize the routing operations in
constrained LLNs. As part of this optimization, RPL requires the constrained LLNs. As part of this optimization, RPL requires the
addition of RPL Packet Information (RPI) in every packet, as defined addition of RPL Packet Information (RPI) in every packet, as defined
in Section 11.2 of [RFC6550]. in Section 11.2 of [RFC6550].
The RPL Option for Carrying RPL Information in Data-Plane Datagrams The RPL Option for Carrying RPL Information in Data-Plane Datagrams
[RFC6553] specification indicates how the RPI can be placed in a RPL [RFC6553] specification indicates how the RPI can be placed in a RPL
Option for use in an IPv6 Hop-by-Hop header. This representation Option for use in an IPv6 Hop-by-Hop header.
demands a total of 8 bytes when in most cases the actual RPI payload
requires only 19 bits. Since the Hop-by-Hop header must not flow
outside of the RPL domain, it must be removed from packets that leave
the domain, and be inserted in packets entering the domain. In both
cases, this operation implies an IP-in-IP encapsulation.
------+--------- ^ This representation demands a total of 8 bytes, while in most cases
| Internet | the actual RPI payload requires only 19 bits. Since the Hop-by-Hop
| | Native IPv6 header must not flow outside of the RPL domain, it must be inserted
+-----+ | in packets entering the domain and be removed from packets that leave
| | Border Router (RPL Root) ^ | ^ the domain. In both cases, this operation implies an IP-in-IP
| | | | | encapsulation.
+-----+ | | | IPv6 in
| | | | IPv6 ------+--------- ^
o o o o | | | + RPI | Internet |
o o o o o o o o o | | | or RH3 | | Native IPv6
o o o o o o o o o o | | | +-----+ |
o o o o o o o o o | | | | | Border Router (RPL Root) ^ | ^
o o o o o o o o v v v | | | | |
o o o o +-----+ | | | IPv6 in
LLN | | | | IPv6
o o o o | | | + RPI
o o o o o o o o o | | | or RH3
o o o o o o o o o o | | |
o o o o o o o o o | | |
o o o o o o o o v v v
o o o o
LLN
Figure 2: IP-in-IP Encapsulation within the LLN. Figure 2: IP-in-IP Encapsulation within the LLN.
Additionally, in the case of the Non-Storing Mode of Operation (MOP), Additionally, in the case of the Non-Storing Mode of Operation (MOP),
RPL requires a Routing Header type 3 (RH3) as defined in the IPv6 RPL requires a Routing Header type 3 (RH3) as defined in the IPv6
Routing Header for Source Routes with RPL [RFC6554] specification, Routing Header for Source Routes with RPL [RFC6554] specification,
for all packets that are routed down a RPL graph. With Non-Storing for all packets that are routed down a RPL graph. With Non-Storing
RPL, even if the source is a node in the same LLN, the packet must RPL, even if the source is a node in the same LLN, the packet must
first reach up the graph to the root so that the root can insert the first reach up the graph to the root so that the root can insert the
RH3 to go down the graph. In any fashion, whether the packet was RH3 to go down the graph. In any fashion, whether the packet was
originated in a node in the LLN or outside the LLN, and regardless of originated in a node in the LLN or outside the LLN, and regardless of
whether the packet stays within the LLN or not, as long as the source whether the packet stays within the LLN or not, as long as the source
of the packet is not the root itself, the source-routing operation of the packet is not the root itself, the source-routing operation
also implies an IP-in-IP encapsulation at the root in order to insert also implies an IP-in-IP encapsulation at the root in order to insert
the RH3. the RH3.
6TiSCH [I-D.ietf-6tisch-architecture] specifies the operation of IPv6 6TiSCH [I-D.ietf-6tisch-architecture] specifies the operation of IPv6
over the TimeSlotted Channel Hopping [RFC7554] (TSCH) mode of over the TimeSlotted Channel Hopping [RFC7554] (TSCH) mode of
operation of IEEE 802.15.4. The architecture requires the use of operation of IEEE 802.15.4. The architecture requires the use of
both RPL and the 6lo adaptation layer over IEEE 802.15.4. Because it both RPL and the 6lo adaptation layer over IEEE 802.15.4. Because it
inherits the constraints on the frame size from the MAC layer, 6TiSCH inherits the constraints on frame size from the MAC layer, 6TiSCH
cannot afford to spend 8 bytes per packet on the RPI. Hence the cannot afford to allocate 8 bytes per packet on the RPI. Hence the
requirement for a 6LoWPAN header compression of the RPI. requirement for 6LoWPAN header compression of the RPI.
An extensible compression technique is required that simplifies IP- An extensible compression technique is required that simplifies IP-
in-IP encapsulation when it is needed, and optimally compresses in-IP encapsulation when it is needed, and optimally compresses
existing routing artifacts found in RPL LLNs. existing routing artifacts found in RPL LLNs.
This specification extends the 6lo adaptation layer framework This specification extends the 6lo adaptation layer framework
([RFC4944],[RFC6282]) so as to carry routing information for route- ([RFC4944],[RFC6282]) so as to carry routing information for route-
over networks based on RPL. The specification includes the formats over networks based on RPL. The specification includes the formats
necessary for RPL and is extensible for additional formats. necessary for RPL and is extensible for additional formats.
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The terms Route-over and Mesh-under are defined in [RFC6775]. The terms Route-over and Mesh-under are defined in [RFC6775].
Other terms in use in LLNs are found in [RFC7228]. Other terms in use in LLNs are found in [RFC7228].
The term "byte" is used in its now customary sense as a synonym for The term "byte" is used in its now customary sense as a synonym for
"octet". "octet".
3. Using the Page Dispatch 3. Using the Page Dispatch
The6LoWPAN Paging Dispatch [I-D.ietf-paging-dispatch] specification The6LoWPAN Paging Dispatch [I-D.ietf-6lo-paging-dispatch]
extends the 6lo adaptation layer framework ([RFC4944], [RFC6282]) by specification extends the 6lo adaptation layer framework ([RFC4944],
introducing a concept of "context" in the 6LoWPAN parser, a context [RFC6282]) by introducing a concept of "context" in the 6LoWPAN
being identified by a Page number. The specification defines 16 parser, a context being identified by a Page number. The
Pages. specification defines 16 Pages.
This draft operates within the Page 1, which is indicated by a This draft operates within Page 1, which is indicated by a Dispatch
Dispatch Value of binary 11110001. Value of binary 11110001.
3.1. New Routing Header Dispatch (6LoRH) 3.1. New Routing Header Dispatch (6LoRH)
This specification introduces a new 6LoWPAN Routing Header (6LoRH) to This specification introduces a new 6LoWPAN Routing Header (6LoRH) to
carry IPv6 routing information. The 6LoRH may contain source routing carry IPv6 routing information. The 6LoRH may contain source routing
information such as a compressed form of RH3, as well as other sorts information such as a compressed form of RH3, as well as other sorts
of routing information such as the RPL Packet Information and IP-in- of routing information such as the RPI and IP-in-IP encapsulation.
IP encapsulation.
The 6LoRH is expressed in a 6loWPAN packet as a Type-Length-Value The 6LoRH is expressed in a 6loWPAN packet as a Type-Length-Value
(TLV) field, which is extensible for future use. (TLV) field, which is extensible for future use.
This specification uses the bit pattern 10xxxxxx in Page 1 for the This specification uses the bit pattern 10xxxxxx in Page 1 for the
new 6LoRH Dispatch and Section 4 describes how RPL artifacts in data new 6LoRH Dispatch. Section 4 describes how RPL artifacts in data
packets can be compressed as 6LoRH headers. packets can be compressed as 6LoRH headers.
3.2. Placement Of The 6LoRH 3.2. Placement Of The 6LoRH
In a zone of a packet where Page 1 is active, which means once a Page Paging Dispatch is parsed and no subsequent Paging Dispatch has been
1 Paging Dispatch is parsed, and as long as no other Paging Dispatch parsed, the parsing of the packet MUST follow this specification if
is parsed, the parsing of the packet MUST follow this specification the 6LoRH Bit Pattern Section 3.1 is found.
if the 6LoRH Bit Pattern Section 3.1 is found.
With this specification, the 6LoRH Dispatch is only defined in Page With this specification, the 6LoRH Dispatch is only defined in Page
context is active. context is active.
One or more 6LoRH header(s) MAY be placed in a 6LoWPAN packet. A One or more 6LoRH header(s) MAY be placed in a 6LoWPAN packet. A
6LoRH header MUST always be placed before the LOWPAN_IPHC as defined 6LoRH header MUST always be placed before the LOWPAN_IPHC as defined
in 6LoWPAN Header Compression [RFC6282]. in 6LoWPAN Header Compression [RFC6282].
A 6LoRH header being always placed in a Page 1 context, it MUST Because a 6LoRH header requires a Page 1 context, it MUST always be
always be placed after any Fragmentation Header and/or Mesh Header placed after any Fragmentation Header and/or Mesh Header [RFC4944].
[RFC4944].
4. 6LoWPAN Routing Header General Format 4. 6LoWPAN Routing Header General Format
The 6LoRH reuses in Page 1 the Dispatch Value Bit Pattern of The 6LoRH reuses in Page 1 the Dispatch Value Bit Pattern of
10xxxxxx. 10xxxxxx.
The Dispatch Value Bit Pattern is split in two forms of 6LoRH: The Dispatch Value Bit Pattern is split in two forms of 6LoRH:
Elective (6LoRHE) that may skipped if not understood Elective (6LoRHE) that may skipped if not understood
skipping to change at page 1, line 308 skipping to change at page 1, line 307
|1|0|1| Length | Type | | |1|0|1| Length | Type | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+
<-- Length --> <-- Length -->
Figure 3: Elective 6LoWPAN Routing Header. Figure 3: Elective 6LoWPAN Routing Header.
Length: Length:
Length of the 6LoRHE expressed in bytes, excluding the first 2 Length of the 6LoRHE expressed in bytes, excluding the first 2
bytes. This enables a node to skip a 6LoRHE header that it does bytes. This enables a node to skip a 6LoRHE header that it does
not support and/or cannot parse, for instance if the Type is not not support and/or cannot parse, for instance if the Type is not
known. recognized.
Type: Type:
Type of the 6LoRHE Type of the 6LoRHE
4.2. Critical Format 4.2. Critical Format
The 6LoRHC uses the Dispatch Value Bit Pattern of 100xxxxx. The 6LoRHC uses the Dispatch Value Bit Pattern of 100xxxxx.
A node which does not support the 6LoRHC Type MUST silently discard A node which does not support the 6LoRHC Type MUST silently discard
the packet. the packet.
Note: The situation where a node receives a message with a Critical Note: The situation where a node receives a message with a Critical
6LoWPAN Routing Header that it does not understand is a critical 6LoWPAN Routing Header that it does not understand is a critical
administrative error whereby the wrong device is placed in a network. administrative error whereby the wrong device is placed in a network.
It makes no sense to overburden the constrained device with code that It makes no sense to overburden the constrained device with code that
would cause ICMP error to the source. Rather, it is expected that would send an ICMP error to the source. Rather, it is expected that
the device will raise some management alert indicating that it cannot the device will raise some management alert indicating that it cannot
operate in this network for that reason. It results that there is no operate in this network for that reason. As a result, there is no
provision for the exchange of error messages for this situation; it provision for the exchange of error messages for this situation, so
should be avoided by judicious use of administrative control and/or it should be avoided by judicious use of administrative control and/
capability indications by the device manufacturer. or capability indications by the device manufacturer.
0 1 0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+
|1|0|0| TSE | Type | | |1|0|0| TSE | Type | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+
<-- Length implied by Type/TSE --> <-- Length implied by Type/TSE -->
Figure 4: Critical 6LoWPAN Routing Header. Figure 4: Critical 6LoWPAN Routing Header.
skipping to change at page 1, line 351 skipping to change at page 1, line 350
Type Specific Extension. The meaning depends on the Type, which Type Specific Extension. The meaning depends on the Type, which
must be known in all of the nodes. The interpretation of the TSE must be known in all of the nodes. The interpretation of the TSE
depends on the Type field that follows. For instance, it may be depends on the Type field that follows. For instance, it may be
used to transport control bits, the number of elements in an used to transport control bits, the number of elements in an
array, or the length of the remainder of the 6LoRHC expressed in a array, or the length of the remainder of the 6LoRHC expressed in a
unit other than bytes. unit other than bytes.
Type: Type:
Type of the 6LoRHC Type of the 6LoRHC
5. The Routing Header Type 3 (RH3) 6LoRH 5. The Routing Header Type 3 (RH3) 6LoRH Header
The Routing Header type 3 (RH3) 6LoRH (RH3-6LoRH) is a Critical The Routing Header type 3 (RH3) 6LoRH (RH3-6LoRH) header is a
6LoWPAN Routing Header that provides a compressed form for the RH3, Critical 6LoWPAN Routing Header that provides a compressed form for
as defined in [RFC6554] for use by RPL routers. Routers that need to the RH3, as defined in [RFC6554] for use by RPL routers. Routers
forward a packet with a RH3-6LoRH are expected to be RPL routers and that need to forward a packet with a RH3-6LoRH are expected to be RPL
are expected to support this specification. If a non-RPL router routers and are expected to support this specification. If a non-RPL
receives a packet with a RH3-6LoRH, this means that there was a router receives a packet with a RH3-6LoRH, this means that there was
routing error and the packet should be dropped so the Type cannot be a routing error and the packet should be dropped so the Type cannot
ignored. be ignored.
0 1 0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- -+- -+ ... +- -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- -+- -+ ... +- -+
|1|0|0| Size |6LoRH Type 0..4| Hop1 | Hop2 | | HopN | |1|0|0| Size |6LoRH Type 0..4| Hop1 | Hop2 | | HopN |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- -+- -+ ... +- -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- -+- -+ ... +- -+
Size indicates the number of compressed addresses Size indicates the number of compressed addresses
Figure 5: The RH3-6LoRH. Figure 5: The RH3-6LoRH.
skipping to change at page 1, line 389 skipping to change at page 1, line 388
+-----------+-----------+ +-----------+-----------+
| 0 | 1 | | 0 | 1 |
| 1 | 2 | | 1 | 2 |
| 2 | 4 | | 2 | 4 |
| 3 | 8 | | 3 | 8 |
| 4 | 16 | | 4 | 16 |
+-----------+-----------+ +-----------+-----------+
Figure 6: The RH3-6LoRH Types. Figure 6: The RH3-6LoRH Types.
In the case of a RH3-6LoRH, the TSE field is used as a Size, which In the case of a RH3-6LoRH header, the TSE field is used as a Size,
encodes the number of hops minus 1; so a Size of 0 means one hop, and which encodes the number of hops minus 1; so a Size of 0 means one
the maximum that can be encoded is 32 hops. (If more than 32 hops hop, and the maximum that can be encoded is 32 hops. (If more than
need to be expressed, a sequence of RH3-6LoRH can be employed.) 32 hops need to be expressed, a sequence of RH3-6LoRH elements can be
employed.)
The Next Hop is indicated in the first entry of the first RH3-6LoRH. The Next Hop is indicated in the first entry of the first RH3-6LoRH
Upon reception, the router checks whether it owns the address header. Upon reception, the router checks whether the address
indicated as Next Hop, which MUST be the case in a strict source indicated as Next Hop is one of its own addresses, which MUST be the
routing environment. If it is so, the entry is removed from the case in a strict source-routing environment. In that case, the entry
RH3-6LoRH and the Size is decremented. If the Size is now zero, the is removed from the RH3-6LoRH header and the Size is decremented. If
whole RH3-6LoRH is removed. If there is no more RH3-6LoRH, the that makes the Size zero, the whole RH3-6LoRH header is removed. If
processing node is the last router on the way, which may or may not there are no more RH3-6LoRH headers, the processing node is the last
be collocated with the final destination. router on the path, which may or may not be collocated with the final
destination.
The last hop in the last RH3-6LoRH is the last router on the way to The last hop in the last RH3-6LoRH is the last router on the way to
the destination in the LLN. In a classical RPL network, all nodes the destination in the LLN. In a classical RPL network, all nodes
are routers so the last hop is effectively the destination as well. are routers so the last hop is effectively the destination as well,
But in the general case, even when there is a RH3-6LoRH header but in the general case, even when there is a RH3-6LoRH header
present, the address of the final destination is always indicated in present, the address of the final destination is always indicated in
the LoWPAN_IPHC [RFC6282]. the LoWPAN_IPHC [RFC6282].
If some bits of the first address in the RH3-6LoRH can be derived If some bits of the first address in the RH3-6LoRH header can be
from the final destination in the LoWPAN_IPHC, then that address may derived from the final destination in the LoWPAN_IPHC, then that
be compressed, otherwise it is expressed as a full IPv6 address of address may be compressed; otherwise it is expressed as a full IPv6
128 bits. Next addresses only need to express the delta from the address of 128 bits. Next addresses only need to express the delta
previous address. from the previous address.
All addresses in a given RH3-6LoRH header are compressed in a same All addresses in a given RH3-6LoRH header are compressed in an
fashion, down to the same number of bytes per address. In order to identical fashion, down to using the identical number of bytes per
get different forms of compression, multiple consecutive RH3-6LoRH address. In order to get different degrees of compression, multiple
must be used. consecutive RH3-6LoRH headers MUST be used
6. The RPL Packet Information 6LoRH 6. The RPL Packet Information 6LoRH
[RFC6550], Section 11.2, specifies the RPL Packet Information (RPI) [RFC6550], Section 11.2, specifies the RPL Packet Information (RPI)
as a set of fields that are placed by RPL routers in IP packets for as a set of fields that are placed by RPL routers in IP packets for
the purpose of Instance Identification, as well as Loop Avoidance and the purpose of Instance Identification, as well as Loop Avoidance and
Detection. Detection.
In particular, the SenderRank, which is the scalar metric computed by In particular, the SenderRank, which is the scalar metric computed by
an specialized Objective Function such as [RFC6552], indicates the a specialized Objective Function such as [RFC6552], indicates the
Rank of the sender and is modified at each hop. The SenderRank field Rank of the sender and is modified at each hop. The SenderRank field
is used to validate that the packet progresses in the expected is used to validate that the packet progresses in the expected
direction, either upwards or downwards, along the DODAG. direction, either upwards or downwards, along the DODAG.
RPL defines the RPL Option for Carrying RPL Information in Data-Plane RPL defines the RPL Option for Carrying RPL Information in Data-Plane
Datagrams [RFC6553] to transport the RPI, which is carried in an IPv6 Datagrams [RFC6553] to transport the RPI, which is carried in an IPv6
Hop-by-Hop Options Header [RFC2460], typically consuming eight bytes Hop-by-Hop Options Header [RFC2460], typically consuming eight bytes
per packet. per packet.
With [RFC6553], the RPL option is encoded as six Octets; it must be With [RFC6553], the RPL option is encoded as six octets, which must
placed in a Hop-by-Hop header that consumes two additional octets for be placed in a Hop-by-Hop header that consumes two additional octets
a total of eight. In order to limit its range to the inside the RPL for a total of eight octets. To limit the header's range to just the
domain, the Hop-by-Hop header must be added to (or removed from) RPL domain, the Hop-by-Hop header must be added to (or removed from)
packets that cross the border of the RPL domain. packets that cross the border of the RPL domain.
The 8-byte overhead is detrimental to the LLN operation, in The 8-byte overhead is detrimental to LLN operation, in particular
particular with regards to bandwidth and battery constraints. These with regards to bandwidth and battery constraints. These bytes may
bytes may cause a containing frame to grow above maximum frame size, cause a containing frame to grow above maximum frame size, leading to
leading to Layer 2 or 6LoWPAN [RFC4944] fragmentation, which in turn Layer 2 or 6LoWPAN [RFC4944] fragmentation, which in turn leads to
causes even more energy spending and issues discussed in the LLN even more energy expenditure and issues discussed in LLN Fragment
Fragment Forwarding and Recovery Forwarding and Recovery [I-D.thubert-6lo-forwarding-fragments].
[I-D.thubert-6lo-forwarding-fragments].
An additional overhead comes from the need, in certain cases, to add An additional overhead comes from the need, in certain cases, to add
an IP-in-IP encapsulation to carry the Hop-by-Hop header. This is an IP-in-IP encapsulation to carry the Hop-by-Hop header. This is
needed when the router that inserts the Hop-by-Hop header is not the needed when the router that inserts the Hop-by-Hop header is not the
source of the packet, so that an error can be returned to the router. source of the packet, so that an error can be returned to the router.
This is also the case when a packet originated by a RPL node must be This is also the case when a packet originated by a RPL node must be
stripped from the Hop-by-Hop header to be routed outside the RPL stripped from the Hop-by-Hop header to be routed outside the RPL
domain. domain.
This specification defines an IPinIP-6LoRH in Section 7 for that For that reason, this specification defines an IP-in-IP-6LoRH header
purpose, but it must be noted that stripping a 6LoRH does not require in Section 7, but it must be noted that removal of a 6LoRH header
a manipulation of the packet in the LOWPAN_IPHC, and thus, if the does not require manipulation of the packet in the LOWPAN_IPHC, and
source address in the LOWPAN_IPHC is the node that inserted the thus, if the source address in the LOWPAN_IPHC is the node that
IPinIP-6LoRH then this alone does not mandate an IPinIP-6LoRH. inserted the IP-in-IP-6LoRH header then this situation alone does not
mandate an IP-in-IP-6LoRH header.
Note: A typical packet in RPL non-storing mode going down the RPL Note: A typical packet in RPL non-storing mode going down the RPL
graph requires an IP-in-IP encapsulating the RH3, whereas the RPI is graph requires an IP-in-IP encapsulation of the RH3, whereas the RPI
usually (and quite illegally) omitted, unless it is important to is usually (and quite illegally) omitted, unless it is important to
indicate the RPLInstanceID. To match this structure, an optimized indicate the RPLInstanceID. To match this structure, an optimized
IP-in-IP 6LoRH is defined in Section 7. IP-in-IP 6LoRH header is defined in Section 7.
As a result, a RPL packet may bear only an RPI-6LoRH and no IPinIP- As a result, a RPL packet may bear only an RPI-6LoRH header and no
6LoRH. In that case, the source and destination of the packet are IP-in-IP-6LoRH header. In that case, the source and destination of
located in the LOWPAN_IPHC. the packet are specified by the LOWPAN_IPHC.
As with [RFC6553], the fields in the RPI include an 'O', an 'R', and As with [RFC6553], the fields in the RPI include an 'O', an 'R', and
an 'F' bit, an 8-bit RPLInstanceID (with some internal structure), an 'F' bit, an 8-bit RPLInstanceID (with some internal structure),
and a 16-bit SenderRank. and a 16-bit SenderRank.
The remainder of this section defines the RPI-6LoRH, a Critical The remainder of this section defines the RPI-6LoRH header, which is
6LoWPAN Routing Header that is designed to transport the RPI in a Critical 6LoWPAN Routing Header that is designed to transport the
6LoWPAN LLNs. RPI in 6LoWPAN LLNs.
6.1. Compressing the RPLInstanceID 6.1. Compressing the RPLInstanceID
RPL Instances are discussed in [RFC6550], Section 5. A number of RPL Instances are discussed in [RFC6550], Section 5. A number of
simple use cases do not require more than one instance, and in such simple use cases do not require more than one instance, and in such
cases, the instance is expected to be the global Instance 0. A cases, the instance is expected to be the global Instance 0. A
global RPLInstanceID is encoded in a RPLInstanceID field as follows: global RPLInstanceID is encoded in a RPLInstanceID field as follows:
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
skipping to change at page 1, line 525 skipping to change at page 1, line 526
idea is used in [RFC6550] by defining DEFAULT_MIN_HOP_RANK_INCREASE idea is used in [RFC6550] by defining DEFAULT_MIN_HOP_RANK_INCREASE
as 256 and in [RFC6552] that defaults MinHopRankIncrease to as 256 and in [RFC6552] that defaults MinHopRankIncrease to
DEFAULT_MIN_HOP_RANK_INCREASE. DEFAULT_MIN_HOP_RANK_INCREASE.
This specification allows to encode the SenderRank as either one or This specification allows to encode the SenderRank as either one or
two bytes, and defines a K flag that, when set, signals that a single two bytes, and defines a K flag that, when set, signals that a single
byte is used. byte is used.
6.3. The Overall RPI-6LoRH encoding 6.3. The Overall RPI-6LoRH encoding
The RPI-6LoRH provides a compressed form for the RPL RPI. Routers The RPI-6LoRH header provides a compressed form for the RPL RPI.
that need to forward a packet with a RPI-6LoRH are expected to be RPL Routers that need to forward a packet with a RPI-6LoRH header are
routers and expected to support this specification. If a non-RPL expected to be RPL routers that support this specification. If a
router receives a packet with a RPI-6LoRH, this means that there was non-RPL router receives a packet with a RPI-6LoRH header, there was a
a routing error and the packet should be dropped so the Type cannot routing error and the packet should be dropped. Thus the Type field
be ignored. MUST NOT be ignored.
Since the I flag is not set, the TSE field does not need to be a Since the I flag is not set, the TSE field does not need to be a
length expressed in bytes. The field is fully reused for control length expressed in bytes. In that case the field is fully reused
bits so as to encode the O, R and F flags from the RPI, and the I and for control bits that encode the O, R and F flags from the RPI, as
K flags that indicate the compression that is taking place. well as the I and K flags that indicate the compression format.
The Type for the RPI-6LoRH is 5. The Type for the RPI-6LoRH is 5.
The RPI-6LoRH is immediately followed by the RPLInstanceID field, The RPI-6LoRH header is immediately followed by the RPLInstanceID
unless that field is fully elided, and then the SenderRank, which is field, unless that field is fully elided, and then the SenderRank,
either compressed into one byte or fully in-lined as the whole 2 which is either compressed into one byte or fully in-lined as two
bytes. The I and K flags in the RPI-6LoRH indicate whether the bytes. The I and K flags in the RPI-6LoRH header indicate whether
RPLInstanceID is elided and/or the SenderRank is compressed and the RPLInstanceID is elided and/or the SenderRank is compressed.
depending on these bits, the Length of the RPI-6LoRH may vary as Depending on these bits, the Length of the RPI-6LoRH may vary as
described hereafter. described hereafter.
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 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... -+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... -+-+-+
|1|0|0|O|R|F|I|K| 6LoRH Type=5 | Compressed fields | |1|0|0|O|R|F|I|K| 6LoRH Type=5 | Compressed fields |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... -+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... -+-+-+
Figure 8: The Generic RPI-6LoRH Format. Figure 8: The Generic RPI-6LoRH Format.
O, R, and F bits: O, R, and F bits: The O, R, and F bits are defined in [RFC6550],
The O, R, and F bits as defined in [RFC6550], Section 11.2. section 11.2.
I bit: I bit: If it is set, the Instance ID is elided and the RPLInstanceID
If it is set, the Instance ID is elided and the RPLInstanceID
is the Global RPLInstanceID 0. If it is not set, the octet is the Global RPLInstanceID 0. If it is not set, the octet
immediately following the type field contains the RPLInstanceID immediately following the type field contains the RPLInstanceID
as specified in [RFC6550] section 5.1. as specified in [RFC6550], section 5.1.
K bit: K bit: If it is set, the SenderRank is compressed into one octet,
If it is set, the SenderRank is be compressed into one octet, with the least significant octet elided. If it is not set, the
and the lowest significant octet is elided. If it is not set, SenderRank, is fully inlined as two octets.
the SenderRank, is fully inlined as 2 octets.
In Figure 9, the RPLInstanceID is the Global RPLInstanceID 0, and the In Figure 9, the RPLInstanceID is the Global RPLInstanceID 0, and the
MinHopRankIncrease is a multiple of 256 so the least significant byte MinHopRankIncrease is a multiple of 256 so the least significant byte
is all zeros and can be elided: is all zeros and can be elided:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|0|0|O|R|F|1|1| 6LoRH Type=5 | SenderRank | |1|0|0|O|R|F|1|1| 6LoRH Type=5 | SenderRank |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 1, line 621 skipping to change at page 1, line 620
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|0|0|O|R|F|0|0| 6LoRH Type=5 | RPLInstanceID | Sender-... |1|0|0|O|R|F|0|0| 6LoRH Type=5 | RPLInstanceID | Sender-...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...-Rank | ...-Rank |
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
I=0, K=0 I=0, K=0
Figure 12: Least compressed form of RPI-6LoRH. Figure 12: Least compressed form of RPI-6LoRH.
7. The IP-in-IP 6LoRH 7. The IP-in-IP 6LoRH Header
The IP-in-IP 6LoRH (IPinIP-6LoRH) is an Elective 6LoWPAN Routing The IP-in-IP 6LoRH (IP-in-IP-6LoRH) header is an Elective 6LoWPAN
Header that provides a compressed form for the encapsulating IPv6 Routing Header that provides a compressed form for the encapsulating
Header in the case of an IP-in-IP encapsulation. IPv6 Header in the case of an IP-in-IP encapsulation.
An IP-in-IP encapsulation is used to insert a field such as a Routing An IP-in-IP encapsulation is used to insert a field such as a Routing
Header or an RPI at a router that is not the source of the packet. Header or an RPI at a router that is not the source of the packet.
In order to send an error back regarding the inserted field, the In order to send an error back regarding the inserted field, the
address of the router that performs the insertion must be provided. address of the router that performs the insertion must be provided.
The encapsulation can also enable the last router prior to The encapsulation can also enable the last router prior to
Destination to remove a field such as the RPI, but this can be done Destination to remove a field such as the RPI, but this can be done
in the compressed form by removing the RPI-6LoRH, so an IPinIP-6LoRH in the compressed form by removing the RPI-6LoRH, so an IP-in-IP-
encapsulation is not required for that sole purpose. 6LoRH encapsulation is not required for that sole purpose.
This field is not critical for routing so the Type can be ignored, This field is not critical for routing so the Type can be ignored,
and the TSE field contains the Length in bytes. and the TSE field contains the Length in bytes.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+
|1|0|1| Length | 6LoRH Type 6 | Hop Limit | Encaps. Address | |1|0|1| Length | 6LoRH Type 6 | Hop Limit | Encaps. Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ... -+
Figure 13: The IPinIP-6LoRH. Figure 13: The IP-in-IP-6LoRH.
The Length of an IPinIP-6LoRH is expressed in bytes and MUST be at The Length of an IP-in-IP-6LoRH header is expressed in bytes and MUST
least 1, to indicate a Hop Limit (HL), that is decremented at each be at least 1, to indicate a Hop Limit (HL), that is decremented at
hop. When the HL reaches 0, the packet is dropped per [RFC2460] each hop. When the HL reaches 0, the packet is dropped per [RFC2460]
If the Length of an IPinIP-6LoRH is exactly 1, then the Encapsulator If the Length of an IP-in-IP-6LoRH header is exactly 1, then the
Address is elided, which means that the Encapsulator is a well-known Encapsulator Address is elided, which means that the Encapsulator is
router, for instance the root in a RPL graph. a well-known router, for instance the root in a RPL graph.
If the Length of an IPinIP-6LoRH is strictly more than 1, then an If the Length of an IP-in-IP-6LoRH header is greater than 1, then an
Encapsulator Address is placed in a compressed form after the Hop Encapsulator Address is placed in a compressed form after the Hop
Limit field. The value of the Length indicates which compression is Limit field. The value of the Length indicates which compression is
performed on the Encapsulator Address. For instance, a Size of 3 performed on the Encapsulator Address. For instance, a Size of 3
indicates that the Encapsulator Address is compressed to 2 bytes. indicates that the Encapsulator Address is compressed to 2 bytes.
When it cannot be elided, the destination IP address of the IP-in-IP When it cannot be elided, the destination IP address of the IP-in-IP
header is transported in a RH3-6LoRH as the first address of the header is transported in a RH3-6LoRH header as the first address of
list. the list.
With RPL, the destination address in the IP-in-IP header is With RPL, the destination address in the IP-in-IP header is
implicitly the root in the RPL graph for packets going upwards, and implicitly the root in the RPL graph for packets going upwards, and
the destination address in the IPHC for packets going downwards. If the destination address in the IPHC for packets going downwards. If
the implicit value is correct, the destination IP address of the IP- the implicit value is correct, the destination IP address of the IP-
in-IP encapsulation can be elided. in-IP encapsulation can be elided.
If the final destination of the packet is a leaf that does not If the final destination of the packet is a leaf that does not
support this specification, then the chain of 6LoRH must be stripped support this specification, then the chain of 6LoRH headers must be
by the RPL/6LR router to which the leaf is attached. In that stripped by the RPL/6LR router to which the leaf is attached. In
example, the destination IP address of the IP-in-IP header cannot be that example, the destination IP address of the IP-in-IP header
elided. cannot be elided.
In the special case where the 6LoRH is used to route 6LoWPAN In the special case where a 6LoRH header is used to route 6LoWPAN
fragments, the destination address is not accessible in the IPHC on fragments, the destination address is not accessible in the IPHC on
all fragments and can be elided only for the first fragment and for all fragments and can be elided only for the first fragment and for
packets going upwards. packets going upwards.
8. Security Considerations 8. Security Considerations
The security considerations of [RFC4944], [RFC6282], and [RFC6553] The security considerations of [RFC4944], [RFC6282], and [RFC6553]
apply. apply.
Using a compressed format as opposed to the full in-line format is Using a compressed format as opposed to the full in-line format is
logically equivalent and does not create an opening for a new threat logically equivalent and is believed to not create an opening for a
when compared to [RFC6550], [RFC6553] and [RFC6554]. new threat when compared to [RFC6550], [RFC6553] and [RFC6554].
9. IANA Considerations 9. IANA Considerations
This specification reserves the Dispatch Value Bit Patterns of This specification reserves Dispatch Value Bit Patterns within the
10xxxxxx within the 6LoWPAN Dispatch Page 1. 6LoWPAN Dispatch Page 1 as follows:
101xxxxx: for Elective 6LoWPAN Routing Headers
100xxxxx: for Critical 6LoWPAN Routing Headers.
9.2. Nex 6LoWPAN Routing Header Type Registry 9.2. Nex 6LoWPAN Routing Header Type Registry
This document creates a IANA registry for the 6LoWPAN Routing Header This document creates an IANA registry for the 6LoWPAN Routing Header
Type, and assigns the following values: Type, and assigns the following values:
0..4 : RH3-6LoRH [RFCthis] 0..4: RH3-6LoRH [RFCthis]
5 : RPI-6LoRH [RFCthis] 5: RPI-6LoRH [RFCthis]
6 : IPinIP-6LoRH [RFCthis] 6: IP-in-IP-6LoRH [RFCthis]
10. Acknowledgments 10. Acknowledgments
The authors wish to thank Thomas Watteyne, Tengfei Chang, Martin The authors wish to thank Tom Phinney, Thomas Watteyne, Tengfei
Turon, James Woodyatt, Samita Chakrabarti, Jonathan Hui, Gabriel Chang, Martin Turon, James Woodyatt, Samita Chakrabarti, Jonathan
Montenegro and Ralph Droms for constructive reviews to the design in Hui, Gabriel Montenegro and Ralph Droms for constructive reviews to
the 6lo Working Group. The overall discussion involved participants the design in the 6lo Working Group. The overall discussion involved
to the 6MAN, 6TiSCH and ROLL WGs, thank you all. Special thanks to participants to the 6MAN, 6TiSCH and ROLL WGs, thank you all.
the chairs of the ROLL WG, Michael Richardson and Ines Robles, and Special thanks to the chairs of the ROLL WG, Michael Richardson and
Brian Haberman, Internet Area A-D, and Adrian Farrel, Routing Area Ines Robles, and Brian Haberman, Internet Area A-D, and Adrian
A-D, for driving this complex effort across Working Groups and Areas. Farrel, Routing Area A-D, for driving this complex effort across
Working Groups and Areas.
11. References 11. References
11.1. Normative References 11.1. Normative References
[I-D.ietf-paging-dispatch] [I-D.ietf-6lo-paging-dispatch]
Thubert, P., "6LoWPAN Paging Dispatch", draft-ietf-paging- Thubert, P., "6LoWPAN Paging Dispatch", draft-ietf-6lo-
dispatch-00 (work in progress), January 2016. paging-dispatch-01 (work in progress), January 2016.
[IEEE802154] [IEEE802154]
IEEE standard for Information Technology, "IEEE std. IEEE standard for Information Technology, "IEEE std.
802.15.4, Part. 15.4: Wireless Medium Access Control (MAC) 802.15.4, Part. 15.4: Wireless Medium Access Control (MAC)
and Physical Layer (PHY) Specifications for Low-Rate and Physical Layer (PHY) Specifications for Low-Rate
Wireless Personal Area Networks", 2015. Wireless Personal Area Networks", 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/ Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
RFC2119, March 1997, RFC2119, March 1997,
skipping to change at page 18, line 36 skipping to change at page 18, line 41
Appendix A. Examples Appendix A. Examples
The example in Figure 14 illustrates the 6LoRH compression of a The example in Figure 14 illustrates the 6LoRH compression of a
classical packet in Storing Mode in all directions, as well as in classical packet in Storing Mode in all directions, as well as in
non-Storing mode for a packet going up the DODAG following the non-Storing mode for a packet going up the DODAG following the
default route to the root. In this particular example, a default route to the root. In this particular example, a
fragmentation process takes place per [RFC4944], and the fragment fragmentation process takes place per [RFC4944], and the fragment
headers must be placed in Page 0 before switching to Page 1: headers must be placed in Page 0 before switching to Page 1:
+- ... -+- ... -+-+ ... -+-+ ... -+- ... +-+-+-+-+-+-+-+-+-+-+- ... +- ... -+- ... -+-+ ... -+-+ ... -+- ... +-+-+-+-+-+-+-+-+-+-+...
|Frag type|Frag hdr |11110001| IPinIP | RPI | Dispatch + LOWPAN_IPHC |Frag type|Frag hdr |11110001|IP-in-IP| RPI | RFC 6282 Dispatch
|RFC 4944 |RFC 4944 | Page 1 | 6LoRH | 6LoRH | RFC 6282 |RFC 4944 |RFC 4944 | Page 1 | 6LoRH | 6LoRH | + LOWPAN_IPHC
+- ... -+- ... -+-+ ... -+-+ ... -+- ... +-+-+-+-+-+-+-+-+-+-+- ... +- ... -+- ... -+-+ ... -+-+ ... -+- ... +-+-+-+-+-+-+-+-+-+-+...
<- RFC 6282 -> <- RFC 6282 ->
No RPL artifact No RPL artifact
Figure 14: Example Compressed Packet with RPI. Figure 14: Example Compressed Packet with RPI.
The example illustrated in Figure 15 is a classical packet in non- The example illustrated in Figure 15 is a classical packet in non-
Storing mode for a packet going down the DODAG following a source Storing mode for a packet going down the DODAG following a source
routed path from the root; in this particular example, addresses in routed path from the root; in this particular example, addresses in
the DODAG are assigned to share a same /112 prefix, for instance the DODAG are assigned to share a same /112 prefix, for instance
taken from a /64 subnet with the first 6 octets of the suffix set to taken from a /64 subnet with the first 6 octets of the suffix set to
a constant such as all zeroes. In that case, all addresses but the a constant such as all zeroes. In that case, all addresses but the
first can be compressed to 2 octets, which means that there will be 2 first can be compressed to 2 octets, which means that there will be 2
RH3_6LoRH headers, one to store the first complete address and the RH3_6LoRH headers, one to store the first complete address and the
one to store the sequence of addresses compressed to 2 octets (in one to store the sequence of addresses compressed to 2 octets (in
this example, 3 of them): this example, 3 of them):
+- ... -+- ... -+-+-+- ... -+-+-+-+-+ ... -+-+-+-+-+-+-+-+-+-+-+- ... +- ... -+- ... -+-+-+- ... -+-+-+-+-+ ... -+-+-+-+-+-+-+-+-+-+-+...
|11110001| IPinIP | RH3(128bits)| RH3(3*16bits)| Dispatch + LOWPAN_IPHC |11110001|IP-in-IP| RH3(128bits)| RH3(3*16bits)| RFC 6282 Dispatch
|Page 1 | 6LoRH | 6LoRH | 6LoRH | RFC 6282 |Page 1 | 6LoRH | 6LoRH | 6LoRH | + LOWPAN_IPHC
+- ... -+- ... +-+-+-+- ... -+-+-+-+-+ ... -+-+-+-+-+-+-+-+-+-+-+- ... +- ... -+- ... +-+-+-+- ... -+-+-+-+-+ ... -+-+-+-+-+-+-+-+-+-+-+...
<- RFC 6282 -> <- RFC 6282 ->
No RPL artifact No RPL artifact
Figure 15: Example Compressed Packet with RH3. Figure 15: Example Compressed Packet with RH3.
Note: the RPI is not represented since most implementations actually Note: the RPI is not represented since most implementations actually
refrain from placing it in a source routed packet though [RFC6550] refrain from placing it in a source routed packet though [RFC6550]
generally expects it. generally expects it.
Authors' Addresses Authors' Addresses
Pascal Thubert (editor) Pascal Thubert (editor)
 End of changes. 64 change blocks. 
207 lines changed or deleted 211 lines changed or added

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