DetNet                                                   P. Thubert, Ed.
Internet-Draft                                             Cisco Systems
Intended status: Standards Track                            11 June 2021
Expires: 13 December 2021


                   IPv6 Hop-by-Hop Options for DetNet
                   draft-pthubert-detnet-ipv6-hbh-03

Abstract

   RFC 8938, the Deterministic Networking Data Plane Framework relies on
   the 6-tuple to identify an IPv6 flow.  But the full DetNet operations
   require also the capabilities to signal meta-information such as a
   sequence within that flow, and to transport different types of
   packets along the same path with the same treatment, e.g.,
   Operations, Administration, and Maintenance packets and/or multiple
   flows with fate and resource sharing.  This document introduces new
   IPv6 Hop-by-Hop options that signal that path and redundancy
   information to the intermediate DetNet relays.

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 13 December 2021.

Copyright Notice

   Copyright (c) 2021 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
   and restrictions with respect to this document.  Code Components



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   extracted from this document must include Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  The DetNet Options  . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  DetNet Redundancy Information Option  . . . . . . . . . .   4
     3.2.  DetNet Path Options . . . . . . . . . . . . . . . . . . .   8
       3.2.1.  DetNet Strict Path Option . . . . . . . . . . . . . .   8
       3.2.2.  DetNet Loose Path Option  . . . . . . . . . . . . . .   9
     3.3.  RPL Packet Information  . . . . . . . . . . . . . . . . .  10
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
     5.1.  New Subregistry for the Redundancy Type . . . . . . . . .  10
     5.2.  New Hop-by-Hop Options  . . . . . . . . . . . . . . . . .  11
   6.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  12
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  13
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   Section 2 of the Deterministic Networking Problem Statement
   [DetNet-PBST] introduces the concept of Deterministic Networking
   (DetNet) to the IETF.  DetNet extends the reach of lower layer
   technologies such as Time-Sensitive Networking (TSN) [IEEE 802.1 TSN]
   and Timeslotted Channel Hopping (TSCH) [IEEE Std. 802.15.4] over IPv6
   and MPLS [RFC8938].

   The "Deterministic Networking Architecture" [DetNet-ARCH] details the
   contribution of layer-3 protocols, and defines three planes: the
   Application (User) Plane, the Controller Plane, and the Network
   Plane.  [DetNet-ARCH] places an emphasis on the centralized model
   whereby a controller instantiates per-flow state in the routers to
   perform adequate forwading operations so as to provide end-to-end
   reliability and bounded latency guarantees.

   The "6TiSCH Architecture" [6TiSCH-ARCH] leverages RPL, the "Routing
   Protocol for Low Power and Lossy Networks" [RPL] and introduces
   concept of a Track as a highly redundant RPL Destination Oriented
   Directed Acyclic Graph (DODAG) rooted at the Track Ingress node, that
   can be installed using so-called projected routes [RPL-PDAO].  In
   that case, the TrackId is an index from a namespace associated to one
   IPv6 address of the Track Ingress node, and the Track that an IPv6



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   packet follows is signaled by the combination of the source address
   (of the Track Ingress node), and the TrackID placed in a RPL Option
   [RFC6553] located in an IPv6 Hop-by-Hop (HbH) Options Header [IPv6]
   in the IPv6 packet.

   The "Reliable and Available Wireless (RAW) Architecture/Framework"
   [RAW-ARCH], extends the DetNet Network Plane to accomodate one or
   multiple hops of homogeneous or heterogeneous wireless technologies,
   e.g. a Wi-Fi6 Mesh or parallel radio access links combining Wi-Fi and
   5G.  The RAW Architecture reuses the concept of Track and introduces
   a new dataplane component, the Path Selection Engine (PSE), to
   dynamically select a subpath and maintain the required quality of
   service within a Track in the face of the rapid evolution of the
   medium properties.

   With [IPv6], the behavior of a router upon an IPv6 packet with a HbH
   Options Header has evolved, making the examination of the header by
   routers along the path optional, as opposed to previously mandatory.
   Additionally, the Option Type for any option in a HbH Options Header
   encodes in the leftmost bits whether a router that inspects the
   header should drop the packet or ignore the option when encountering
   an unknown option.  Combined, these capabilities enable a larger use
   of the header beyond the boundaries of a limited domain, as
   examplified by the change of behavior of the RPL data plane, that was
   changed to allow a packet with a RPL option to escape the RPL domain
   in the larger Internet [RFC9008].

   "IPv6 Hop-by-Hop Options Processing Procedures" [HbH-UPDT] further
   specifies the procedures for how IPv6 Hop-by-Hop options are
   processed to make their processing even more practical and increase
   their use in the Internet.  In that context, it makes sense to
   consider Hop-by-Hop Options to transport the information that is
   relevant to DetNet.

   The "Deterministic Networking Data Plane Framework" [RFC8938] relies
   on the 6-tuple to identify an IPv6 flow.  But the full DetNet
   operations require also the capabilities to signal meta-information
   such as a sequence within that flow, and to transport different types
   of packets along the same path with the same treatment.  For
   instance, it is required that Operations, Administration, and
   Maintenance (OAM) [RFC6291] packets and/or multiple flows share the
   same fate and resource sharing over the same Track or the same
   Traffic Engineered (TE) [RFC3272] DetNet path.

   This document introduces new IPv6 Hop-by-Hop options that signal
   DetNet path and redundancy information to the intermediate relays in
   an abstract form that is independent of the transport layer.
   Transported in IPv6 HbH Options, the DetNet information is available



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   early in the header chain of the packet and can be added by a service
   instance as part of the encapsulation by the Ingress of the DetNet
   path.  It can then be accessed by the intermediate DetNet routers
   without the need of a deep packet inspection (e.g., beyond UDP).

2.  Terminology

   Timestamp semantics and timestamp formats used in this document are
   defined in "Guidelines for Defining Packet Timestamps" [RFC8877].

   The Deterministic Networking terms used in this document are defined
   in the "Deterministic Networking Architecture" [DetNet-ARCH].

   The terms Track and TrackID are defined in the "6TiSCH Architecture"
   [6TiSCH-ARCH].

3.  The DetNet Options

   This document defines new IPv6 options for DetNet to signal path and
   a sequence to the DetNet layers.  Those options are to be placed in
   an IPv6 HbH Options Header.  The format of the options follow the
   generic definition in section 4.2 of [IPv6].

   If a DetNet Path option (see Section 3.2), including the RPL Option,
   is present in the same HbH Option Header as a DetNet Redundancy
   Information option (see Section 3.1), then the redundancy information
   applies to the signaled path across all flows that traverse that
   path; else the redundancy information applies to the flow indicated
   by the 6-tuple [RFC8938].

3.1.  DetNet Redundancy Information Option

   The DetNet Redundancy Information Option helps discriminate copies of
   a same packet vs. different packets, and is useful for service-
   sublayer Packet Replication Elimination and Ordering Functions
   (PREOF).  The typical expression redundancy information is a sequence
   counter, but it is not the only way to identify a packet.  It is also
   possible that a packet is divided in elements such as network-coded
   fragments.  In that case, the pieces are discriminated with an opaque
   8-bit fragment tag.











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   A packet sequence can be expressed uniquely as a wrapping counter,
   represented as an unsigned integer in the option.  In that case, the
   size of the representation MUST be large enough to cover at least 3
   times the upper bound on out-of-order packet delivery in terms of
   number of packets.  The sequence counter may be copied from a field
   in another protocol, and it is possible that the value 0 is reserved
   when wrapping, to the option offers both possibilities, wrapping to
   either 0 or to 1.

   This specification also allows to use a time stamp for the packet
   redundancy information, in conformance with the recommendations in
   [RFC8877].  This can be accomplished by utilizing the Precision Time
   Protocol (PTP) format defined in IEEE Std. 1588 [IEEE Std. 1588] or
   Network Time Protocol (NTP) [RFC5905] formats.  In that case, the
   timestamp resolution at the origin node that builds the option MUST
   be fine enough to ensure that two consecutive packets are never
   stamped with the same value.  There is no requirement for this
   particular stamping function that the sense of time at the origin
   node is synchronized with the rest of the DetNet network.

   IEEEE TSN [IEEE 802.1 TSN] defined a redundancy tag (R-Tag) for the
   IEEE Std. 802.1CB Frame Replication and Elimination for Reliability
   (FRER).  The R-Tag is a structured field and its content is subject
   to evolve; but the expectation for this specification is that the
   overall size remains 48 bits and that the 48-bit value is different
   for a large number of contiguous frames.  When transporting TSN
   frames in a DetNet packet, it is possible to leverage the R-Tag as
   Redundancy information, though it cannot be assumed that the R-Tag is
   sequentially incremented; so it can be used for packet duplicate
   elimination but it is not suitable not for packet re-ordering.

   This specification also allows for an hybrid model with a coarse
   grained packet sequence within a coarse grained time stamp.  In that
   case, both a time stamp option and a wrapping counter options are
   found, and the counter is used to compare packets with the same time
   stamp and ignored otherwise In that case, the size of the
   representation of the counter MUST be large enough to cover at least
   3 times the number of packets that may be sent with the same value of
   time stamp.












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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Option Type  |  Opt Data Len |  R.I. Type    | Fragment Tag  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     .                                                               .
     .          Redundancy Information (variable Size)               .
     .                                                               .
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 1: Redundancy Information Option Format

   Redundancy Information Option fields:

   Option Type:  8-bit identifier of the type of option.  Value TBD by
      IANA; if the processing IPv6 node does not recognize the Option
      Type it MUST skip over this option and continue processing the
      header (act =00); the Option Data of that option cannot change en
      route to the packet's final destination (chg=0).  The

   Opt Data Len:  8-bit length of the option data.

   Fragment Tag:  8-bit field, set to 0 when the packet is sent in
      entirety; packets with the same Redundancy Information and
      different fragments tags MUST be considered as different by the
      elimination function and are not subject to ordering based on the
      Tag.

   Redundancy Information Type:  8-bit identifier of the type of
      Redundancy information.  Value to be confirmed by IANA.



















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      +=======+============+===============+===========================+
      |  Seq. | Category   | Common Name   | Redundancy                |
      |  Type |            |               | Information Format        |
      | Value |            |               |                           |
      +=======+============+===============+===========================+
      |   1   | Wrapping   | Basic         | 32-bit unsigned           |
      |       | Counter    | Sequence      | integer                   |
      |       |            | Counter       |                           |
      +-------+============+---------------+---------------------------+
      |   2   | Wrapping   | Zero-avoiding | 32-bit unsigned           |
      |       | Counter    | Sequence      | integer, wraps to 1       |
      |       |            | Counter       |                           |
      +-------+============+---------------+---------------------------+
      |   3   | Wrapping   | RPL Sequence  | 8-bit RPL sequence,       |
      |       | Counter    | Counter       | see section 7.  of        |
      |       |            |               | [RPL]                     |
      +-------+============+---------------+---------------------------+
      |   11  | Time Stamp | Fractional    | NTP 64-bit Timestamp      |
      |       |            | NTP           | Format, see section       |
      |       |            |               | 4.2.1.  of [RFC8877]      |
      +-------+============+---------------+---------------------------+
      |   12  | Time Stamp | Short NTP     | NTP 32-bit Timestamp      |
      |       |            |               | Format, see section       |
      |       |            |               | 4.2.2.  of [RFC8877]      |
      +-------+============+---------------+---------------------------+
      |   13  | Time Stamp | PTP           | PTP 80-bit Timestamp      |
      |       |            |               | Format, see [IEEE         |
      |       |            |               | Std. 1588]                |
      +-------+============+---------------+---------------------------+
      |   14  | Time Stamp | Short PTP     | PTP 64-bit Truncated      |
      |       |            |               | Timestamp Format,         |
      |       |            |               | see section 4.3. of       |
      |       |            |               | [RFC8877]                 |
      +-------+============+---------------+---------------------------+
      |   24  | Structured | TSN           | 48-bit opaque             |
      |       | Unique Tag | Redundancy    |                           |
      |       |            | Tag           |                           |
      +-------+============+---------------+---------------------------+

           Table 1: Redundancy Information Type values (suggested)

   Redundancy Information:  Variable size, as indicated in Table 1.









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3.2.  DetNet Path Options

   The DetNet Path Options carry path information that is independent
   from the flows transported.  When present, it is the information that
   MUST be used to select the DetNet state at the DetNet forwarding
   sublayer.

   The path indicated therein is used by the service sublayer, as it is
   the scope where the redundancy information is unique across a number
   of packets large enough to ensure that a forwarding node never has to
   handle different packets with the same redundancy information, though
   the same value may be found for packets with a different path
   information.

   The typical DetNet path is is contained under a single administrative
   control or within a closed group of administrative control; these
   include campus-wide networks and private WANs [DetNet-ARCH].  The
   typical expectation is that all nodes along a DetNet path are aware
   of the path and actively maintain a forwarding state for it.  The
   DetNet Strict Path Option (see Section 3.2.1) is designed for that
   environment; if a packet escapes the local domain, a router that does
   not support the option will intercept it and return an error to the
   source.

   In other environments such as RAW, it might be that the service-layer
   protection concentrates on just segments of the end-to-end path.  In
   that case, the service-sublayer protection may require the signaling
   of both redundancy and path information, though the path information
   is potentially not used by some intermediate routers.  The path
   information may also relate to segments are installed along the path
   using a DetNet forwarding state as opposed to, say, SRv6.  In either
   case the DetNet Loose Path Option Section 3.2.2 can be used to signal
   the path without incurring an ICMP Error from an intermediate node.

   DetNet can also leverage the RPL Option that signals a Track in the
   RPL Packet Information (RPI) [RFC6553].  There are 2 versions of the
   RPL option, defined respectively in [RPL] with the act bits [IPv6]
   set to dropped the packet when the option is unknown, that defined
   in[RFC9008] which let the option be ignored.

3.2.1.  DetNet Strict Path Option

   In complement to the RPL option, this specification defines a
   protocol-independent Strict Path Identifier, which is also taken from
   a namespace indicated by the IPv6 source address of the packet.

   The DetNet Strict Path Option is to be used in a limited domain and
   all routers along the path are expected to support the option.



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   An intermediate router that supports the DetNet Strict Path Option
   but is missing the necessary state to forward along the indicated
   path must drop the packet and return an ICMP error.code 0 pointing at
   the offset of the Strict Path ID in the DetNet Strict Path Option.

     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Option Type  |  Opt Data Len |    Strict Path ID              |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                 Figure 2: DetNet Strict Path Option Format

   Redundancy Option fields:

   Option Type:  8-bit identifier of the type of option.  Value TBD by
      IANA; if the processing IPv6 node does not recognize the Option
      Type it must discard the packet and send an ICMP Parameter
      Problem, Code 2, message to the packet's Source Address (act =10);
      the Option Data of that option cannot change en route to the
      packet's final destination (chg=0).

   Opt Data Len:  8-bit length of the option data, set to 2.

   Strict Path ID:  16-bit identifier of the DetNet Path, taken from a
      local namespace associated with the IPv6 source address of the
      packet.

3.2.2.  DetNet Loose Path Option

   The DetNet Loose Path Option transports a Loose Path identifier which
   is taken from a namespace indicated by the Origin Autonomous System
   (AS).  When the DetNet path is contained within a single AS, the
   Origin Autonomous System field can be left to 0 indicating local AS.

   The DetNet Loose Path Option is to be used to signal a path that may
   be loose and may exceed the boundaries of a local domain; a portion
   of the hops may traverse routers in the wider internet that will not
   leverage the option and are expected to ignore it.

   An intermediate router that supports the DetNet Loose Path Option but
   is missing the necessary state to forward along the indicated path
   must ignore the DetNet Loose Path Option.








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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Option Type  |  Opt Data Len |   Origin Autonomous System    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Loose Path ID                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                 Figure 3: DetNet Loose Path Option Format

   Redundancy Option fields:

   Option Type:  8-bit identifier of the type of option.  Value TBD by
      IANA; if the processing IPv6 node does not recognize the Option
      Type it MUST skip over this option and continue processing the
      header (act =00); the Option Data of that option cannot change en
      route to the packet's final destination (chg=0).

   Opt Data Len:  8-bit length of the option data, set to 6.

   Origin Autonomous System:  16-bit identifier of the Autonomous
      Systems (AS) that originates the path.

   Loose Path ID:  32-bit identifier of the DetNet Path, taken from a
      local namespace associated with the origin AS of the DetNet path.
      The value of 0 signals a DetNet path that is constrained within
      the local AS or the local administrative DetNet domain.

3.3.  RPL Packet Information

   6TiSCH [6TiSCH-ARCH] and RAW [RAW-ARCH] signal a Track using a RPL
   Option [RFC6553] with a RPLInstanceID used as TrackID.  This
   specification reuses the RPL option as a method to signal a DetNet
   path.  In that case, the Projected-Route 'P' flag [RPL-PDAO] MUST be
   set to 1, and the O, R, F flags, as well as the Sender Rank field,
   MUST be set to 0 by the originator, forwarded as-is, and ignored on
   reception.

4.  Security Considerations

5.  IANA Considerations

5.1.  New Subregistry for the Redundancy Type

   This specification creates a new Subregistry for the "Redundancy Type
   of the Redundancy Option" under the "Internet Protocol Version 6
   (IPv6) Parameters" registry [IPV6-PARMS].




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   *  Possible values are 8-bit unsigned integers (0..255).

   *  Registration procedure is "IETF Review" [RFC8126].

   *  Initial allocation is as Suggested in Table 2:

     +-----------------+--------------------------------+-----------+
     | Suggested Value | Meaning                        | Reference |
     +-----------------+--------------------------------+-----------+
     |        1        | Basic Sequence Counter         | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        2        | Zero-avoiding Sequence Counter | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        3        | RPL Sequence Counter           | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        11       | Fractional NTP time stamp      | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        12       | Short NTP time stamp           | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        13       | PTP time stamp                 | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        14       | Short PTP time stamp           | THIS RFC  |
     +-----------------+--------------------------------+-----------+
     |        24       | TSN Redundancy Tag             | THIS RFC  |
     +-----------------+--------------------------------+-----------+

               Table 2: Redundancy Information Type values

5.2.  New Hop-by-Hop Options

   This specification updates the "Destination Options and Hop-by-Hop
   Options" under the "Internet Protocol Version 6 (IPv6) Parameters"
   registry [IPV6-PARMS] with the (suggested) values below:

       +------+-----+-----+-------+--------------------+-----------+
       | Hexa | act | chg | rest  | Description        | Reference |
       +------+-----+-----+-------+--------------------+-----------+
       | 0x12 | 00  | 0   | 10010 | DetNet Redundancy  | THIS RFC  |
       |      |     |     |       | Information Option |           |
       +------+-----+-----+-------+--------------------+-----------+
       | 0x93 | 10  | 0   | 10011 | DetNet Strict Path | THIS RFC  |
       |      |     |     |       | Option             |           |
       +------+-----+-----+-------+--------------------+-----------+
       | 0x14 | 00  | 0   | 10100 | DetNet Loose Path  | THIS RFC  |
       |      |     |     |       | Option             |           |
       +------+-----+-----+-------+--------------------+-----------+

                     Table 3: DetNet Hop-by-Hop Options



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6.  Acknowledgments

   TBD

7.  References

7.1.  Normative References

   [RPL]      Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J.,
              Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur,
              JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
              Low-Power and Lossy Networks", RFC 6550,
              DOI 10.17487/RFC6550, March 2012,
              <https://www.rfc-editor.org/info/rfc6550>.

   [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,
              <https://www.rfc-editor.org/info/rfc6553>.

   [IPv6]     Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", STD 86, RFC 8200,
              DOI 10.17487/RFC8200, July 2017,
              <https://www.rfc-editor.org/info/rfc8200>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [RFC8877]  Mizrahi, T., Fabini, J., and A. Morton, "Guidelines for
              Defining Packet Timestamps", RFC 8877,
              DOI 10.17487/RFC8877, September 2020,
              <https://www.rfc-editor.org/info/rfc8877>.

   [HbH-UPDT] Hinden, R. M. and G. Fairhurst, "IPv6 Hop-by-Hop Options
              Processing Procedures", Work in Progress, Internet-Draft,
              draft-hinden-6man-hbh-processing-00, 3 December 2020,
              <https://tools.ietf.org/html/draft-hinden-6man-hbh-
              processing-00>.

   [DetNet-ARCH]
              Finn, N., Thubert, P., Varga, B., and J. Farkas,
              "Deterministic Networking Architecture", RFC 8655,
              DOI 10.17487/RFC8655, October 2019,
              <https://www.rfc-editor.org/info/rfc8655>.




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   [RFC9008]  Robles, M.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", RFC 9008,
              DOI 10.17487/RFC9008, April 2021,
              <https://www.rfc-editor.org/info/rfc9008>.

   [6TiSCH-ARCH]
              Thubert, P., Ed., "An Architecture for IPv6 over the Time-
              Slotted Channel Hopping Mode of IEEE 802.15.4 (6TiSCH)",
              RFC 9030, DOI 10.17487/RFC9030, May 2021,
              <https://www.rfc-editor.org/info/rfc9030>.

   [RAW-ARCH] Thubert, P., Papadopoulos, G. Z., and R. Buddenberg,
              "Reliable and Available Wireless Architecture/Framework",
              Work in Progress, Internet-Draft, draft-pthubert-raw-
              architecture-05, 15 November 2020,
              <https://tools.ietf.org/html/draft-pthubert-raw-
              architecture-05>.

7.2.  Informative References

   [RPL-PDAO] Thubert, P., Jadhav, R. A., and M. Gillmore, "Root
              initiated routing state in RPL", Work in Progress,
              Internet-Draft, draft-ietf-roll-dao-projection-16, 15
              January 2021, <https://tools.ietf.org/html/draft-ietf-
              roll-dao-projection-16>.

   [RFC6291]  Andersson, L., van Helvoort, H., Bonica, R., Romascanu,
              D., and S. Mansfield, "Guidelines for the Use of the "OAM"
              Acronym in the IETF", BCP 161, RFC 6291,
              DOI 10.17487/RFC6291, June 2011,
              <https://www.rfc-editor.org/info/rfc6291>.

   [RFC5905]  Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
              "Network Time Protocol Version 4: Protocol and Algorithms
              Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
              <https://www.rfc-editor.org/info/rfc5905>.

   [DetNet-PBST]
              Finn, N. and P. Thubert, "Deterministic Networking Problem
              Statement", RFC 8557, DOI 10.17487/RFC8557, May 2019,
              <https://www.rfc-editor.org/info/rfc8557>.

   [RFC3272]  Awduche, D., Chiu, A., Elwalid, A., Widjaja, I., and X.
              Xiao, "Overview and Principles of Internet Traffic
              Engineering", RFC 3272, DOI 10.17487/RFC3272, May 2002,
              <https://www.rfc-editor.org/info/rfc3272>.




Thubert                 Expires 13 December 2021               [Page 13]


Internet-Draft             DetNet HbH Options                  June 2021


   [RFC8938]  Varga, B., Ed., Farkas, J., Berger, L., Malis, A., and S.
              Bryant, "Deterministic Networking (DetNet) Data Plane
              Framework", RFC 8938, DOI 10.17487/RFC8938, November 2020,
              <https://www.rfc-editor.org/info/rfc8938>.

   [IEEE Std. 802.15.4]
              IEEE standard for Information Technology, "IEEE Std.
              802.15.4, Part. 15.4: Wireless Medium Access Control (MAC)
              and Physical Layer (PHY) Specifications for Low-Rate
              Wireless Personal Area Networks".

   [IEEE 802.1 TSN]
              IEEE 802.1, "Time-Sensitive Networking (TSN) Task Group",
              <http://www.ieee802.org/1/pages/tsn.html>.

   [IEEE Std. 1588]
              IEEE, "IEEE Standard for a Precision Clock Synchronization
              Protocol for Networked Measurement and Control Systems",
              IEEE Standard 1588,
              <https://ieeexplore.ieee.org/document/4579760/>.

   [IPV6-PARMS]
              IANA, "Internet Protocol Version 6 (IPv6) Parameters",
              <https://www.iana.org/assignments/ipv6-parameters/
              ipv6-parameters.xhtml>.

Author's Address

   Pascal Thubert (editor)
   Cisco Systems, Inc
   France

   Phone: +33 497 23 26 34
   Email: pthubert@cisco.com

















Thubert                 Expires 13 December 2021               [Page 14]