--- 1/draft-ietf-roll-turnon-rfc8138-08.txt 2020-07-27 08:13:16.277637035 -0700 +++ 2/draft-ietf-roll-turnon-rfc8138-09.txt 2020-07-27 08:13:16.301637646 -0700 @@ -1,43 +1,43 @@ ROLL P. Thubert, Ed. Internet-Draft L. Zhao Updates: 8138 (if approved) Cisco Systems -Intended status: Standards Track 8 July 2020 -Expires: 9 January 2021 +Intended status: Standards Track 27 July 2020 +Expires: 28 January 2021 A RPL DODAG Configuration Option for the 6LoWPAN Routing Header - draft-ietf-roll-turnon-rfc8138-08 + draft-ietf-roll-turnon-rfc8138-09 Abstract - This document updates RFC 8138 and RFC 6550 by defining a bit in the - RPL DODAG Configuration Option to indicate whether RFC 8138 - compression is used within the RPL Instance, and specify the behavior - of RFC 8138-capable nodes when the bit is set and reset. + This document updates RFC 8138 by defining a bit in the RPL DODAG + Configuration Option to indicate whether compression is used within + the RPL Instance, and specify the behavior of RFC 8138-capable nodes + when the bit is set and reset. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on 9 January 2021. + This Internet-Draft will expire on 28 January 2021. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights @@ -54,22 +54,22 @@ 2.2. Glossary . . . . . . . . . . . . . . . . . . . . . . . . 3 2.3. Requirements Language . . . . . . . . . . . . . . . . . . 4 3. The RPL DODAG Configuration Option . . . . . . . . . . . . . 4 4. Updating RFC 8138 . . . . . . . . . . . . . . . . . . . . . . 5 5. Transition Scenarios . . . . . . . . . . . . . . . . . . . . 5 5.1. Coexistence . . . . . . . . . . . . . . . . . . . . . . . 6 5.2. Inconsistent State While Migrating . . . . . . . . . . . 6 5.3. Rolling Back . . . . . . . . . . . . . . . . . . . . . . 6 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 - 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8 - 9. Normative References . . . . . . . . . . . . . . . . . . . . 8 + 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 7 + 9. Normative References . . . . . . . . . . . . . . . . . . . . 7 10. Informative References . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 1. Introduction The packet compression technique defined in [RFC8138] can only be activated in a RPL [RFC6550] network when all the nodes support it. Otherwise, a non-capable node acting as leaf-only would fail to communicate, and acting as a router it would drop the compressed packets and black-hole a portion of the network. @@ -168,35 +168,35 @@ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type = 0x04 |Opt Length = 14| Flags |A| ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | ... | Figure 1: DODAG Configuration Option (Partial View) This specification defines a new flag "Enable RFC8138 Compression" (T). The "T" flag is set to turn-on the use of the compression of RPL artifacts with [RFC8138] within the DODAG. The new "T" flag is - encoded in one of the reserved bits in the RPL DODAG Configuration - Option. The suggested bit position of the "T" flag is indicated in - Section 6. + encoded in the Flags field in the RPL DODAG Configuration Option. + The suggested bit position of the "T" flag is indicated in Section 6. - /[RFC6550] states, [RFC6550] states, when referring to the DODAG - Configuration Option, that "Nodes other than the DODAG Root MUST NOT - modify this information when propagating the DODAG Configuration - option". Therefore, even a legacy parent propagates the "T" flag as - set by the Root whether it supports this specification or not. So - when the "T" flag is set, it is transparently flooded to all the - nodes in the DODAG. + [RFC6550] states, when referring to the DODAG Configuration Option, + that "Nodes other than the DODAG Root MUST NOT modify this + information when propagating the DODAG Configuration option". + Therefore, a legacy parent propagates the "T" flag as set by the Root + whether it supports this specification or not. So when the "T" flag + is set, it is transparently flooded to all the nodes in the DODAG. - Section 6.3.1. of [RFC6550] defines a 3-bit Mode of Operation (MOP) - in the DIO Base Object. The new "T" flag is defined only for MOP - value between 0 to 6. + Section 6.3.1 of [RFC6550] defines a 3-bit Mode of Operation (MOP) in + the DIO Base Object. For MOP values 0 to 6, the use of compression + depends on the "T" flag as specified in this document. A MOP value + of 7 and above MUST use compression by default and ignore the setting + of the "T" flag. 4. Updating RFC 8138 A node SHOULD source packets in the compressed form using [RFC8138] if and only if the "T" flag is set. This behaviour can be overridden by e.g., configuration or network management. Overriding may be needed e.g., to cope with a legacy implementations of the Root that supports [RFC8138] but not this specification and cannot set the "T" flag. @@ -251,23 +251,23 @@ able to handle compressed packets in the compressed form. A node that cannot do so may remain connected to the network as a RUL, but how the node is modified to turn into a RUL is out of scope. 5.2. Inconsistent State While Migrating When the "T" flag is turned on by the Root, the information slowly percolates through the DODAG as the DIO gets propagated. Some nodes will see the flag and start sourcing packets in the compressed form while other nodes in the same RPL DODAG are still not aware of it. - Conversely, in non-storing mode, the Root will start using [RFC8138] - with a Source Routing Header 6LoRH (SRH-6LoRH) that routes all the - way to the parent router or to the leaf. + In non-storing mode, the Root will start using [RFC8138] with a + Source Routing Header 6LoRH (SRH-6LoRH) that routes all the way to + the parent router or to the leaf. To ensure that a packet is forwarded across the RPL DODAG in the form in which it was generated, it is required that all the RPL nodes support [RFC8138] at the time of the switch. Setting the "T" flag is ultimately the responsibility of the Network Administrator. The expectation is that the network management or upgrading tools in place enable the Network Administrator to know when all the nodes that may join a DODAG were migrated. In the case of a RPL instance with multiple Roots, all nodes that participate to @@ -293,30 +293,20 @@ as follows: +---------------+---------------------------------+-----------+ | Bit Number | Capability Description | Reference | +---------------+---------------------------------+-----------+ | 2 (suggested) | Turn on RFC8138 Compression (T) | THIS RFC | +---------------+---------------------------------+-----------+ Table 1: New DODAG Configuration Option Flag - The DODAG Configuration Option Flags defined so far will be obsolete - for RPL Mode of Operation (MOP) above and including 7. - - IANA is requested to update the name of the Registry from "DODAG - Configuration Option Flags" to "DODAG Configuration Option Flags for - RPL MOP 0..6". - - When MOP values of 7 and more are defined, a new registry will be - needed. - 7. Security Considerations First of all, it is worth noting that with [RFC6550], every node in the LLN that is RPL-aware can inject any RPL-based attack in the network. A trust model has to be put in place in an effort to exclude rogue nodes from participating to the RPL and the 6LoWPAN signaling, as well as from the data packet exchange. This trust model could be at a minimum based on a Layer-2 Secure joining and the Link-Layer security. This is a generic RPL and 6LoWPAN requirement, see Req5.1 in Appendix of [RFC8505]. @@ -363,45 +353,45 @@ [RFC7102] Vasseur, JP., "Terms Used in Routing for Low-Power and Lossy Networks", RFC 7102, DOI 10.17487/RFC7102, January 2014, . [RFC8138] Thubert, P., Ed., Bormann, C., Toutain, L., and R. Cragie, "IPv6 over Low-Power Wireless Personal Area Network (6LoWPAN) Routing Header", RFC 8138, DOI 10.17487/RFC8138, April 2017, . + [RFC8505] Thubert, P., Ed., Nordmark, E., Chakrabarti, S., and C. + Perkins, "Registration Extensions for IPv6 over Low-Power + Wireless Personal Area Network (6LoWPAN) Neighbor + Discovery", RFC 8505, DOI 10.17487/RFC8505, November 2018, + . + + [UNAWARE-LEAVES] + Thubert, P. and M. Richardson, "Routing for RPL Leaves", + Work in Progress, Internet-Draft, draft-ietf-roll-unaware- + leaves-18, 12 June 2020, . + 10. Informative References [RFC6553] Hui, J. and JP. Vasseur, "The Routing Protocol for Low- Power and Lossy Networks (RPL) Option for Carrying RPL Information in Data-Plane Datagrams", RFC 6553, DOI 10.17487/RFC6553, March 2012, . [RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for Constrained-Node Networks", RFC 7228, DOI 10.17487/RFC7228, May 2014, . - [RFC8505] Thubert, P., Ed., Nordmark, E., Chakrabarti, S., and C. - Perkins, "Registration Extensions for IPv6 over Low-Power - Wireless Personal Area Network (6LoWPAN) Neighbor - Discovery", RFC 8505, DOI 10.17487/RFC8505, November 2018, - . - - [UNAWARE-LEAVES] - Thubert, P. and M. Richardson, "Routing for RPL Leaves", - Work in Progress, Internet-Draft, draft-ietf-roll-unaware- - leaves-18, 12 June 2020, . - [USEofRPLinfo] Robles, I., Richardson, M., and P. Thubert, "Using RPI Option Type, Routing Header for Source Routes and IPv6-in- IPv6 encapsulation in the RPL Data Plane", Work in Progress, Internet-Draft, draft-ietf-roll-useofrplinfo-40, 25 June 2020, . Authors' Addresses