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Versions: 00

DetNet                                                     B. Varga, Ed.
Internet-Draft                                                 J. Farkas
Intended status: Standards Track                                Ericsson
Expires: November 6, 2019                                       A. Malis
                                                               S. Bryant
                                                     Huawei Technologies
                                                             J. Korhonen
                                                             May 5, 2019


 DetNet Data Plane: IP over IEEE 802.1 Time Sensitive Networking (TSN)
                    draft-ietf-detnet-ip-over-tsn-00

Abstract

   This document specifies the Deterministic Networking IP data plane
   when operating over a TSN network.

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 November 6, 2019.

Copyright Notice

   Copyright (c) 2019 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 extracted from this document must
   include Simplified BSD License text as described in Section 4.e of




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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Terms Used In This Document . . . . . . . . . . . . . . .   3
     2.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Requirements Language . . . . . . . . . . . . . . . . . . . .   4
   4.  DetNet IP Data Plane Overview . . . . . . . . . . . . . . . .   4
   5.  DetNet IP Data Plane Considerations . . . . . . . . . . . . .   7
     5.1.  DetNet Routers  . . . . . . . . . . . . . . . . . . . . .   8
     5.2.  Networks With Multiple Technology Segments  . . . . . . .   9
   6.  Mapping DetNet IP Flows to IEEE 802.1 TSN . . . . . . . . . .  10
     6.1.  TSN Stream ID Mapping . . . . . . . . . . . . . . . . . .  11
     6.2.  TSN Usage of FRER . . . . . . . . . . . . . . . . . . . .  13
     6.3.  Procedures  . . . . . . . . . . . . . . . . . . . . . . .  14
   7.  Management and Control Implications . . . . . . . . . . . . .  14
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  16
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  16
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  16
     11.1.  Normative references . . . . . . . . . . . . . . . . . .  16
     11.2.  Informative references . . . . . . . . . . . . . . . . .  18
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  21

1.  Introduction

   [Editor's note: Introduction to be made specific to DetNet IP over
   TSN scenario.  May be similar to intro of DetNet MPLS over TSN.].

   Deterministic Networking (DetNet) is a service that can be offered by
   a network to DetNet flows.  DetNet provides these flows extremely low
   packet loss rates and assured maximum end-to-end delivery latency.
   General background and concepts of DetNet can be found in the DetNet
   Architecture [I-D.ietf-detnet-architecture].

   This document specifies the DetNet data plane operation for IP hosts
   and routers that provide DetNet service to IP encapsulated data.  No
   DetNet specific encapsulation is defined to support IP flows, rather
   existing IP and higher layer protocol header information is used to
   support flow identification and DetNet service delivery.

   The DetNet Architecture decomposes the DetNet related data plane
   functions into two sub-layers: a service sub-layer and a forwarding
   sub-layer.  The service sub-layer is used to provide DetNet service
   protection and reordering.  The forwarding sub-layer is used to



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   provides congestion protection (low loss, assured latency, and
   limited reordering).  As no DetNet specific headers are added to
   support DetNet IP flows, only the forwarding sub-layer functions are
   supported using the DetNet IP defined by this document.  Service
   protection can be provided on a per sub-net basis using technologies
   such as MPLS [I-D.ietf-detnet-dp-sol-mpls] and IEEE802.1 TSN.

2.  Terminology

   [Editor's note: Needs clean up.].

2.1.  Terms Used In This Document

   This document uses the terminology and concepts established in the
   DetNet architecture [I-D.ietf-detnet-architecture], and the reader is
   assumed to be familiar with that document and its terminology.

2.2.  Abbreviations

   The following abbreviations used in this document:

   CE            Customer Edge equipment.

   CoS           Class of Service.

   DetNet        Deterministic Networking.

   DF            DetNet Flow.

   L2            Layer-2.

   L3            Layer-3.

   LSP           Label-switched path.

   MPLS          Multiprotocol Label Switching.

   OAM           Operations, Administration, and Maintenance.

   PE            Provider Edge.

   PREOF         Packet Replication, Ordering and Elimination Function.

   PSN           Packet Switched Network.

   PW            Pseudowire.

   QoS           Quality of Service.



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   TE            Traffic Engineering.

   TSN           Time-Sensitive Networking, TSN is a Task Group of the
                 IEEE 802.1 Working Group.

3.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

4.  DetNet IP Data Plane Overview

   [Editor's note: simplify this section and highlight DetNet IP over
   subnets scenario being the focus in the remaining part of the
   document.].

   This document describes how IP is used by DetNet nodes, i.e., hosts
   and routers, to identify DetNet flows and provide a DetNet service.
   From a data plane perspective, an end-to-end IP model is followed.
   As mentioned above, existing IP and higher layer protocol header
   information is used to support flow identification and DetNet service
   delivery.

   DetNet uses "6-tuple" based flow identification, where "6-tuple"
   refers to information carried in IP and higher layer protocol
   headers.  General background on the use of IP headers, and
   "5-tuples", to identify flows and support Quality of Service (QoS)
   can be found in [RFC3670].  [RFC7657] also provides useful background
   on the delivery differentiated services (DiffServ) and "6-tuple"
   based flow identification.

   DetNet flow aggregation may be enabled via the use of wildcards,
   masks, prefixes and ranges.  IP tunnels may also be used to support
   flow aggregation.  In these cases, it is expected that DetNet aware
   intermediate nodes will provide DetNet service assurance on the
   aggregate through resource allocation and congestion control
   mechanisms.











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    DetNet IP       Relay                        Relay       DetNet IP
    End System      Node                         Node        End System

   +----------+                                             +----------+
   |   Appl.  |<------------ End to End Service ----------->|   Appl.  |
   +----------+  ............                 ...........   +----------+
   | Service  |<-: Service  :-- DetNet flow --: Service  :->| Service  |
   +----------+  +----------+                 +----------+  +----------+
   |Forwarding|  |Forwarding|                 |Forwarding|  |Forwarding|
   +--------.-+  +-.------.-+                 +-.---.----+  +-------.--+
            : Link :       \      ,-----.      /     \   ,-----.   /
            +......+        +----[  Sub  ]----+       +-[  Sub  ]-+
                                 [Network]              [Network]
                                  `-----'                `-----'

            |<--------------------- DetNet IP --------------------->|

             Figure 1: A Simple DetNet (DN) Enabled IP Network

   Figure 1 illustrates a DetNet enabled IP network.  The DetNet enabled
   end systems originate IP encapsulated traffic that is identified as
   DetNet flows, relay nodes understand the forwarding requirements of
   the DetNet flow and ensure that node, interface and sub-network
   resources are allocated to ensure DetNet service requirements.  The
   dotted line around the Service component of the Relay Nodes indicates
   that the transit routers are DetNet service aware but do not perform
   any DetNet service sub-layer function, e.g., PREOF.  IEEE 802.1 TSN
   is an example sub-network type which can provide support for DetNet
   flows and service.  The mapping of DetNet IP flows to TSN streams and
   TSN protection mechanisms is covered in Section 6.

   Note: The sub-network can represent a TSN, MPLS or IP network
   segment.


















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   DetNet IP       Relay         Transit         Relay       DetNet IP
   End System      Node           Node           Node        End System

  +----------+                                              +----------+
  |   Appl.  |<-------------- End to End Service ---------->|   Appl.  |
  +----------+   .....-----+                  +-----.....   +----------+
  | Service  |<--: Service |-- DetNet flow ---| Service :-->| Service  |
  |          |   :         |<- DN MPLS flow ->|         :   |          |
  +----------+   +---------+   +----------+   +---------+   +----------+
  |Forwarding|   |Fwd| |Fwd|   |Forwarding|   |Fwd| |Fwd|   |Forwarding|
  +--------.-+   +-.-+ +-.-+   +---.----.-+   +-.-+ +-.-+   +----.-----+
           :  Link :    /  ,-----.  \   :  Link :    /  ,-----.  \
           +.......+    +-[  Sub  ]-+   +.......+   +--[  Sub  ]--+
                          [Network]                    [Network]
                           `-----'                      `-----'

                         |<---- DetNet MPLS --->|
           |<--------------------- DetNet IP ------------------->|

               Figure 2: DetNet IP Over DetNet MPLS Network

   Figure 2 illustrates a variant of Figure 1, with an MPLS based DetNet
   network as a sub-network between the relay nodes.  It shows a more
   complex DetNet enabled IP network where an IP flow is mapped to one
   or more PWs and MPLS (TE) LSPs.  The end systems still originate IP
   encapsulated traffic that is identified as DetNet flows.  The relay
   nodes follow procedures defined in RRR to map each DetNet flow to
   MPLS LSPs.  While not shown, relay nodes can provide service sub-
   layer functions such as PREOF using DetNet over MPLS, and this is
   indicated by the solid line for the MPLS facing portion of the
   Service component.  Note that the Transit node is MPLS (TE) LSP aware
   and performs switching based on MPLS labels, and need not have any
   specific knowledge of the DetNet service or the corresponding DetNet
   flow identification.  See RRR for details on the mapping of IP flows
   to MPLS, and [I-D.ietf-detnet-dp-sol-mpls] for general support of
   DetNet services using MPLS.















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   IP              Edge                         Edge         IP
   End System      Node                         Node         End System

  +----------+   +.........+                  +.........+   +----------+
  |   Appl.  |<--:Svc Proxy:-- E2E Service ---:Svc Proxy:-->|   Appl.  |
  +----------+   +.........+                  +.........+   +----------+
  |    IP    |<--:IP : :Svc:----- IP flow ----:Svc: :IP :-->|    IP    |
  +----------+   +---+ +---+                  +---+ +---+   +----------+
  |Forwarding|   |Fwd| |Fwd|                  |Fwd| |Fwd|   |Forwarding|
  +--------.-+   +-.-+ +-.-+                  +-.-+ +-.-+   +---.------+
           :  Link :      \       ,-----.      /     /  ,-----.  \
           +.......+       +-----[  Sub  ]----+     +--[  Sub  ]--+
                                 [Network]             [Network]
                                  `-----'               `-----'

        |<--- IP --->| |<------ DetNet IP ------->| |<--- IP --->|

      Figure 3: Non-DetNet aware IP end systems with DetNet IP Domain

   Figure 3 illustrates another variant of Figure 1 where the end
   systems are not DetNet aware.  In this case, edge nodes sit at the
   boundary of the DetNet domain and provide DetNet service proxies for
   the end applications by initiating and terminating DetNet service for
   the application's IP flows.  The existing header information or an
   approach used for aggregation can be used to support DetNet flow
   identification.

   Non-DetNet and DetNet IP packets are identical on the wire.  From
   data plane perspective, the only difference is that there is flow-
   associated DetNet information on each DetNet node that defines the
   flow related characteristics and required forwarding behavior.  As
   shown above, edge nodes provide a Service Proxy function that
   "associates" one or more IP flows with the appropriate DetNet flow-
   specific information and ensures that the receives the proper traffic
   treatment within the domain.

   Note: The operation of IEEE802.1 TSN end systems over DetNet enabled
   IP networks is not described in this document.  While TSN flows could
   be encapsulated in IP packets by an IP End System or DetNet Edge Node
   in order to produce DetNet IP flows, the details of such are out of
   scope of this document.

5.  DetNet IP Data Plane Considerations

   [Editor's note: Sort out what data plane considerations are relevant
   for sub-net scenarios.].





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5.1.  DetNet Routers

   Within a DetNet domain, the DetNet enabled IP Routers interconnect
   links and sub-networks to support end-to-end delivery of DetNet
   flows.  From a DetNet architecture perspective, these routers are
   DetNet relays, as they must be DetNet service aware.  Such routers
   identify DetNet flows based on the IP 6-tuple, and ensure that the
   DetNet service required traffic treatment is provided both on the
   node and on any attached sub-network.

   This solution provides DetNet functions end to end, but does so on a
   per link and sub-network basis.  Congestion protection and latency
   control and the resource allocation (queuing, policing, shaping) are
   supported using the underlying link / sub net specific mechanisms.
   However, service protections (packet replication and packet
   elimination functions) are not provided at the DetNet layer end to
   end.  But such service protection can be provided on a per underlying
   L2 link and sub-network basis.

                     +------+                         +------+
                     |  X   |                         |  X   |
                     +======+                         +------+
          End-system |  IP  |                         |  IP  |
                -----+------+-------+======+---     --+======+--
          DetNet                    |L2/SbN|          |L2/SbN|
                                    +------+          +------+


   Figure 4: Encapsulation of DetNet Routing in simplified IP service L3
                                end-systems

   The DetNet Service Flow is mapped to the link / sub-network specific
   resources using an underlying system specific means.  This implies
   each DetNet aware node on path looks into the forwarded DetNet
   Service Flow packet and utilize e.g., a 5- (or 6-) tuple to find out
   the required mapping within a node.

   As noted earlier, the Service Protection is done within each link /
   sub-network independently using the domain specific mechanisms (due
   the lack of a unified end to end sequencing information that would be
   available for intermediate nodes).  Therefore, service protection (if
   any) cannot be provided end-to-end, only within sub-networks.  This
   is shown for a three sub-network scenario in Figure 5, where each
   sub-network can provide service protection between its borders.







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                                    ______
                          ____     /      \__
               ____      /     \__/          \___   ______
   +----+   __/    +====+                       +==+      \     +----+
   |src |__/ SubN1  )   |                       |  \ SubN3 \____| dst|
   +----+  \_______/    \       Sub-Network2    |   \______/    +----+
                         \_                    _/
                           \         __     __/
                            \_______/  \___/


             +---+        +---------E--------+      +-----+
   +----+    |   |        |         |        |      |     |      +----+
   |src |----R   E--------R     +---+        E------R     E------+ dst|
   +----+    |   |        |     |            |      |     |      +----+
             +---+        +-----R------------+      +-----+


    Figure 5: Replication and elimination in sub-networks for DetNet IP
                                 networks

   If end to end service protection is desired that can be implemented,
   for example, by the DetNet end systems using Layer-4 (L4) transport
   protocols or application protocols.  However, these are out of scope
   of this document.

5.2.  Networks With Multiple Technology Segments

   There are network scenarios, where the DetNet domain contains
   multiple technology segments (IEEE 802.1 TSN, MPLS) and all those
   segments are under the same administrative control (see Figure 6).
   Furthermore, DetNet nodes may be interconnected via TSN segments.

   DetNet routers ensure that detnet service requirements are met per
   hop by allocating local resources, both receive and transmit, and by
   mapping the service requirements of each flow to appropriate sub-
   network mechanisms.  Such mapping is sub-network technology specific.
   The mapping of DetNet IP Flows to MPLS is covered RRR .  The mapping
   of IP DetNet Flows to IEEE 802.1 TSN is covered in Section 6.












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                                      ______
                            _____    /      \__
               ____        /     \__/          \___    ______
   +----+   __/    +======+                        +==+      \   +----+
   |src |__/  Seg1  )     |                        |  \  Seg3 \__| dst|
   +----+  \_______+      \        Segment-2       |   \+_____/  +----+
                    \======+__                    _+===/
                              \         __     __/
                               \_______/  \___/


         Figure 6: DetNet domains and multiple technology segments

6.  Mapping DetNet IP Flows to IEEE 802.1 TSN

   [Authors note: how do we handle control protocols such as ICMP,
   IPsec, etc.]

   This section covers how DetNet IP flows operate over an IEEE 802.1
   TSN sub-network.  Figure 7 illustrates such a scenario, where two IP
   (DetNet) nodes are interconnected by a TSN sub-network.  Node-1 is
   single homed and Node-2 is dual-homed.  IP nodes can be (1) DetNet IP
   End System, (2) DetNet IP Edge or Relay node or (3) IP End System.

       IP (DetNet)                   IP (DetNet)
         Node-1                        Node-2

      ............                  ............
   <--: Service  :-- DetNet flow ---: Service  :-->
      +----------+                  +----------+
      |Forwarding|                  |Forwarding|
      +--------.-+    <-TSN Str->   +-.-----.--+
                \      ,-------.     /     /
                 +----[ TSN-Sub ]---+     /
                      [ Network ]--------+
                       `-------'
   <----------------- DetNet IP ----------------->

      Figure 7: DetNet (DN) Enabled IP Network over a TSN sub-network

   The Time-Sensitive Networking (TSN) Task Group of the IEEE 802.1
   Working Group have defined (and are defining) a number of amendments
   to IEEE 802.1Q [IEEE8021Q] that provide zero congestion loss and
   bounded latency in bridged networks.  Furthermore IEEE 802.1CB
   [IEEE8021CB] defines frame replication and elimination functions for
   reliability that should prove both compatible with and useful to,
   DetNet networks.  All these functions have to identify flows those
   require TSN treatment.



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   As is the case for DetNet, a Layer 2 network node such as a bridge
   may need to identify the specific DetNet flow to which a packet
   belongs in order to provide the TSN/DetNet QoS for that packet.  It
   also may need additional marking, such as the priority field of an
   IEEE Std 802.1Q VLAN tag, to give the packet proper service.

   TSN capabilities of the TSN sub-network are made available for IP
   (DetNet) flows via the protocol interworking function defined in IEEE
   802.1CB [IEEE8021CB].  For example, applied on the TSN edge port
   connected to the IP (DetNet) node it can convert an ingress unicast
   IP (DetNet) flow to use a specific multicast destination MAC address
   and VLAN, in order to direct the packet through a specific path
   inside the bridged network.  A similar interworking pair at the other
   end of the TSN sub-network would restore the packet to its original
   destination MAC address and VLAN.

   Placement of TSN functions depends on the TSN capabilities of nodes.
   IP (DetNet) Nodes may or may not support TSN functions.  For a given
   TSN Stream (i.e., DetNet flow) an IP (DetNet) node is treated as a
   Talker or a Listener inside the TSN sub-network.

6.1.  TSN Stream ID Mapping

   DetNet IP Flow and TSN Stream mapping is based on the active Stream
   Identification function, that operates at the frame level.  IEEE
   802.1CB [IEEE8021CB] defines an Active Destination MAC and VLAN
   Stream identification function, what can replace some Ethernet header
   fields namely (1) the destination MAC-address, (2) the VLAN-ID and
   (3) priority parameters with alternate values.  Replacement is
   provided for the frame passed down the stack from the upper layers or
   up the stack from the lower layers.

   Active Destination MAC and VLAN Stream identification can be used
   within a Talker to set flow identity or a Listener to recover the
   original addressing information.  It can be used also in a TSN bridge
   that is providing translation as a proxy service for an End System.
   As a result IP (DetNet) flows can be mapped to use a particular {MAC-
   address, VLAN} pair to match the Stream in the TSN sub-network.

   From the TSN sub-network perspective DetNet IP nodes without any TSN
   functions can be treated as TSN-unaware Talker or Listener.  In such
   cases relay nodes in the TSN sub-network MUST modify the Ethernet
   encapsulation of the DetNet IP flow (e.g., MAC translation, VLAN-ID
   setting, Sequence number addition, etc.) to allow proper TSN specific
   handling of the flow inside the sub-network.  This is illustrated in
   Figure 8.





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        IP (DetNet)
          Node-1
      <---------->

      ............
   <--: Service  :-- DetNet flow ------------------
      +----------+
      |Forwarding|
      +----------+    +---------------+
      |    L2    |    | L2 Relay with |<--- TSN ----
      |          |    | TSN function  |    Stream
      +-----.----+    +--.---------.--+
             \__________/           \______

       TSN-unaware
        Talker /          TSN-Bridge
        Listener             Relay
                    <-------- TSN sub-network -------

             Figure 8: IP (DetNet) node without TSN functions

   IP (DetNet) nodes being TSN-aware can be treated as a combination of
   a TSN-unaware Talker/Listener and a TSN-Relay, as shown in Figure 9.
   In such cases the IP (DetNet) node MUST provide the TSN sub-network
   specific Ethernet encapsulation over the link(s) towards the sub-
   network.  An TSN-aware IP (DetNet) node MUST support the following
   TSN components:

   1.  For recognizing flows:

       *  Stream Identification

   2.  For FRER used inside the TSN domain, additionally:

       *  Sequencing function

       *  Sequence encode/decode function

   3.  For FRER when the node is a replication or elimination point,
       additionally:

       *  Stream splitting function

       *  Individual recovery function

   [Editor's note: Should we added here requirements regarding IEEE
   802.1Q C-VLAN component?]




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                  IP (DetNet)
                     Node-2
      <---------------------------------->

      ............
   <--: Service  :-- DetNet flow ------------------
      +----------+
      |Forwarding|
      +----------+    +---------------+
      |    L2    |    | L2 Relay with |<--- TSN ---
      |          |    | TSN function  |    Stream
      +-----.----+    +--.------.---.-+
             \__________/        \   \______
                                  \_________
       TSN-unaware
        Talker /          TSN-Bridge
        Listener             Relay
                                          <----- TSN Sub-network -----
      <------- TSN-aware Tlk/Lstn ------->

               Figure 9: IP (DetNet) node with TSN functions

   A Stream identification component MUST be able to instantiate the
   following functions (1) Active Destination MAC and VLAN Stream
   identification function, (2) IP Stream identification function and
   (3) the related managed objects in Clause 9 of IEEE 802.1CB
   [IEEE8021CB].  IP Stream identification function provides a 6-tuple
   match.

   The Sequence encode/decode function MUST support the Redundancy tag
   (R-TAG) format as per Clause 7.8 of IEEE 802.1CB [IEEE8021CB].

6.2.  TSN Usage of FRER

   TSN Streams supporting DetNet flows may use Frame Replication and
   Elimination for Redundancy (FRER) [802.1CB] based on the loss service
   requirements of the TSN Stream, which is derived from the DetNet
   service requirements of the DetNet mapped flow.  The specific
   operation of FRER is not modified by the use of DetNet and follows
   IEEE 802.1CB [IEEE8021CB].

   FRER function and the provided service recovery is available only
   within the TSN sub-network (as shown in Figure 5) as the Stream-ID
   and the TSN sequence number are not valid outside the sub-network.
   An IP (DetNet) node represents a L3 border and as such it terminates
   all related information elements encoded in the L2 frames.





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6.3.  Procedures

   [Editor's note: This section is TBD - covers required behavior of a
   TSN-aware DetNet node using a TSN underlay.]

   This section provides DetNet IP data plane procedures to interwork
   with a TSN underlay sub-network when the IP (DetNet) node acts as a
   TSN-aware Talker or Listener (see Figure 9).  These procedures have
   been divided into the following areas: flow identification, mapping
   of a DetNet flow to a TSN Stream and ensure proper TSN encapsulation.

   Flow identification procedures are described in RRR .  A TSN-aware IP
   (DetNet) node SHALL support the Stream Identification TSN components
   as per IEEE 802.1CB [IEEE8021CB].

   Implementations of this document SHALL use management and control
   information to map a DetNet flow to a TSN Stream.  N:1 mapping
   (aggregating DetNet flows in a single TSN Stream) SHALL be supported.
   The management or control function that provisions flow mapping SHALL
   ensure that adequate resources are allocated and configured to
   provide proper service requirements of the mapped flows.

   For proper TSN encapsulation implementations of this document SHALL
   support active Stream Identification function as defined in chapter
   6.6 in IEEE 802.1CB [IEEE8021CB].

   A TSN-aware IP (DetNet) node SHALL support Ethernet encapsulation
   with Redundancy tag (R-TAG) as per chapter 7.8 in IEEE 802.1CB
   [IEEE8021CB].

   Depending whether FRER functions are used in the TSN sub-network to
   serve the mapped TSN Stream, a TSN-aware IP (DetNet) node SHALL
   support Sequencing function and Sequence encode/decode function as
   per chapter 7.4 and 7.6 in IEEE 802.1CB [IEEE8021CB].  Furthermore
   when a TSN-aware IP (DetNet) node acting as a replication or
   elimination point for FRER it SHALL implement the Stream splitting
   function and the Individual recovery function as per chapter 7.7 and
   7.5 in IEEE 802.1CB [IEEE8021CB].

7.  Management and Control Implications

   [Editor's note: This section is TBD Covers Creation, mapping, removal
   of TSN Stream IDs, related parameters and,when needed, configuration
   of FRER.  Supported by management/control plane.]

   DetNet flow and TSN Stream mapping related information are required
   only for TSN-aware IP (DetNet) nodes.  From the Data Plane




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   perspective there is no practical difference based on the origin of
   flow mapping related information (management plane or control plane).

   TSN-aware DetNet IP nodes are member of both the DetNet domain and
   the TSN sub-network.  Within the TSN sub-network the TSN-aware IP
   (DetNet) node has a TSM-aware Talker/Listener role, so TSN specific
   management and control plane functionalities must be implemented.
   There are many similarities in the management plane techniques used
   in DetNet and TSN, but that is not the case for the control plane
   protocols.  For example, RSVP-TE and MSRP behaves differently.
   Therefore management and control plane design is an important aspect
   of scenarios, where mapping between DetNet and TSN is required.

   In order to use a TSN sub-network between DetNet nodes, DetNet
   specific information must be converted to TSN sub-network specific
   ones.  DetNet flow ID and flow related parameters/requirements must
   be converted to a TSN Stream ID and stream related parameters/
   requirements.  Note that, as the TSN sub-network is just a portion of
   the end2end DetNet path (i.e., single hop from IP perspective), some
   parameters (e.g., delay) may differ significantly.  Other parameters
   (like bandwidth) also may have to be tuned due to the L2
   encapsulation used in the TSN sub-network.

   In some case it may be challenging to determine some TSN Stream
   related information.  For example on a TSN-aware IP (DetNet) node
   that acts as a Talker, it is quite obvious which DetNet node is the
   Listener of the mapped TSN stream (i.e., the IP Next-Hop).  However
   it may be not trivial to locate the point/interface where that
   Listener is connected to the TSN sub-network.  Such attributes may
   require interaction between control and management plane functions
   and between DetNet and TSN domains.

   Mapping between DetNet flow identifiers and TSN Stream identifiers,
   if not provided explicitly, can be done by a TSN-aware IP (DetNet)
   node locally based on information provided for configuration of the
   TSN Stream identification functions (IP Stream identification and
   active Stream identification function).

   Triggering the setup/modification of a TSN Stream in the TSN sub-
   network is an example where management and/or control plane
   interactions are required between the DetNet and TSN sub-network.
   TSN-unaware IP (DetNet) nodes make such a triggering even more
   complicated as they are fully unaware of the sub-network and run
   independently.

   Configuration of TSN specific functions (e.g., FRER) inside the TSN
   sub-network is a TSN specific decision and may not be visible in the
   DetNet domain.



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8.  Security Considerations

   The security considerations of DetNet in general are discussed in
   [I-D.ietf-detnet-architecture] and [I-D.ietf-detnet-security].  Other
   security considerations will be added in a future version of this
   draft.

9.  IANA Considerations

   TBD.

10.  Acknowledgements

   Thanks for Norman Finn and Lou Berger for their comments and
   contributions.

11.  References

11.1.  Normative references

   [RFC0768]  Postel, J., "User Datagram Protocol", STD 6, RFC 768,
              DOI 10.17487/RFC0768, August 1980,
              <https://www.rfc-editor.org/info/rfc768>.

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              DOI 10.17487/RFC0791, September 1981,
              <https://www.rfc-editor.org/info/rfc791>.

   [RFC0793]  Postel, J., "Transmission Control Protocol", STD 7,
              RFC 793, DOI 10.17487/RFC0793, September 1981,
              <https://www.rfc-editor.org/info/rfc793>.

   [RFC1812]  Baker, F., Ed., "Requirements for IP Version 4 Routers",
              RFC 1812, DOI 10.17487/RFC1812, June 1995,
              <https://www.rfc-editor.org/info/rfc1812>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2211]  Wroclawski, J., "Specification of the Controlled-Load
              Network Element Service", RFC 2211, DOI 10.17487/RFC2211,
              September 1997, <https://www.rfc-editor.org/info/rfc2211>.







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   [RFC2212]  Shenker, S., Partridge, C., and R. Guerin, "Specification
              of Guaranteed Quality of Service", RFC 2212,
              DOI 10.17487/RFC2212, September 1997,
              <https://www.rfc-editor.org/info/rfc2212>.

   [RFC2474]  Nichols, K., Blake, S., Baker, F., and D. Black,
              "Definition of the Differentiated Services Field (DS
              Field) in the IPv4 and IPv6 Headers", RFC 2474,
              DOI 10.17487/RFC2474, December 1998,
              <https://www.rfc-editor.org/info/rfc2474>.

   [RFC3168]  Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
              of Explicit Congestion Notification (ECN) to IP",
              RFC 3168, DOI 10.17487/RFC3168, September 2001,
              <https://www.rfc-editor.org/info/rfc3168>.

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
              <https://www.rfc-editor.org/info/rfc3209>.

   [RFC3270]  Le Faucheur, F., Wu, L., Davie, B., Davari, S., Vaananen,
              P., Krishnan, R., Cheval, P., and J. Heinanen, "Multi-
              Protocol Label Switching (MPLS) Support of Differentiated
              Services", RFC 3270, DOI 10.17487/RFC3270, May 2002,
              <https://www.rfc-editor.org/info/rfc3270>.

   [RFC3473]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Resource ReserVation Protocol-
              Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
              DOI 10.17487/RFC3473, January 2003,
              <https://www.rfc-editor.org/info/rfc3473>.

   [RFC4302]  Kent, S., "IP Authentication Header", RFC 4302,
              DOI 10.17487/RFC4302, December 2005,
              <https://www.rfc-editor.org/info/rfc4302>.

   [RFC4303]  Kent, S., "IP Encapsulating Security Payload (ESP)",
              RFC 4303, DOI 10.17487/RFC4303, December 2005,
              <https://www.rfc-editor.org/info/rfc4303>.

   [RFC5462]  Andersson, L. and R. Asati, "Multiprotocol Label Switching
              (MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic
              Class" Field", RFC 5462, DOI 10.17487/RFC5462, February
              2009, <https://www.rfc-editor.org/info/rfc5462>.






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   [RFC6003]  Papadimitriou, D., "Ethernet Traffic Parameters",
              RFC 6003, DOI 10.17487/RFC6003, October 2010,
              <https://www.rfc-editor.org/info/rfc6003>.

   [RFC7608]  Boucadair, M., Petrescu, A., and F. Baker, "IPv6 Prefix
              Length Recommendation for Forwarding", BCP 198, RFC 7608,
              DOI 10.17487/RFC7608, July 2015,
              <https://www.rfc-editor.org/info/rfc7608>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8200]  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>.

11.2.  Informative references

   [G.8275.1]
              International Telecommunication Union, "Precision time
              protocol telecom profile for phase/time synchronization
              with full timing support from the network", ITU-T
              G.8275.1/Y.1369.1 G.8275.1, June 2016,
              <https://www.itu.int/rec/T-REC-G.8275.1/en>.

   [G.8275.2]
              International Telecommunication Union, "Precision time
              protocol telecom profile for phase/time synchronization
              with partial timing support from the network", ITU-T
              G.8275.2/Y.1369.2 G.8275.2, June 2016,
              <https://www.itu.int/rec/T-REC-G.8275.2/en>.

   [I-D.ietf-detnet-architecture]
              Finn, N., Thubert, P., Varga, B., and J. Farkas,
              "Deterministic Networking Architecture", draft-ietf-
              detnet-architecture-12 (work in progress), March 2019.

   [I-D.ietf-detnet-dp-sol-mpls]
              Korhonen, J. and B. Varga, "DetNet MPLS Data Plane
              Encapsulation", draft-ietf-detnet-dp-sol-mpls-02 (work in
              progress), March 2019.

   [I-D.ietf-detnet-flow-information-model]
              Farkas, J., Varga, B., Cummings, R., and Y. Jiang, "DetNet
              Flow Information Model", draft-ietf-detnet-flow-
              information-model-03 (work in progress), March 2019.



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   [I-D.ietf-detnet-security]
              Mizrahi, T., Grossman, E., Hacker, A., Das, S., Dowdell,
              J., Austad, H., Stanton, K., and N. Finn, "Deterministic
              Networking (DetNet) Security Considerations", draft-ietf-
              detnet-security-04 (work in progress), March 2019.

   [I-D.ietf-teas-pce-native-ip]
              Wang, A., Zhao, Q., Khasanov, B., Chen, H., and R. Mallya,
              "PCE in Native IP Network", draft-ietf-teas-pce-native-
              ip-03 (work in progress), April 2019.

   [IEEE1588]
              IEEE, "IEEE 1588 Standard for a Precision Clock
              Synchronization Protocol for Networked Measurement and
              Control Systems Version 2", 2008.

   [IEEE8021CB]
              Finn, N., "Draft Standard for Local and metropolitan area
              networks - Seamless Redundancy", IEEE P802.1CB
              /D2.1 P802.1CB, December 2015,
              <http://www.ieee802.org/1/files/private/cb-drafts/
              d2/802-1CB-d2-1.pdf>.

   [IEEE8021Q]
              IEEE 802.1, "Standard for Local and metropolitan area
              networks--Bridges and Bridged Networks (IEEE Std 802.1Q-
              2014)", 2014, <http://standards.ieee.org/about/get/>.

   [RFC1122]  Braden, R., Ed., "Requirements for Internet Hosts -
              Communication Layers", STD 3, RFC 1122,
              DOI 10.17487/RFC1122, October 1989,
              <https://www.rfc-editor.org/info/rfc1122>.

   [RFC2205]  Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
              September 1997, <https://www.rfc-editor.org/info/rfc2205>.

   [RFC2386]  Crawley, E., Nair, R., Rajagopalan, B., and H. Sandick, "A
              Framework for QoS-based Routing in the Internet",
              RFC 2386, DOI 10.17487/RFC2386, August 1998,
              <https://www.rfc-editor.org/info/rfc2386>.

   [RFC3670]  Moore, B., Durham, D., Strassner, J., Westerinen, A., and
              W. Weiss, "Information Model for Describing Network Device
              QoS Datapath Mechanisms", RFC 3670, DOI 10.17487/RFC3670,
              January 2004, <https://www.rfc-editor.org/info/rfc3670>.




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   [RFC5575]  Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
              and D. McPherson, "Dissemination of Flow Specification
              Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
              <https://www.rfc-editor.org/info/rfc5575>.

   [RFC5654]  Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed.,
              Sprecher, N., and S. Ueno, "Requirements of an MPLS
              Transport Profile", RFC 5654, DOI 10.17487/RFC5654,
              September 2009, <https://www.rfc-editor.org/info/rfc5654>.

   [RFC5777]  Korhonen, J., Tschofenig, H., Arumaithurai, M., Jones, M.,
              Ed., and A. Lior, "Traffic Classification and Quality of
              Service (QoS) Attributes for Diameter", RFC 5777,
              DOI 10.17487/RFC5777, February 2010,
              <https://www.rfc-editor.org/info/rfc5777>.

   [RFC6434]  Jankiewicz, E., Loughney, J., and T. Narten, "IPv6 Node
              Requirements", RFC 6434, DOI 10.17487/RFC6434, December
              2011, <https://www.rfc-editor.org/info/rfc6434>.

   [RFC7551]  Zhang, F., Ed., Jing, R., and R. Gandhi, Ed., "RSVP-TE
              Extensions for Associated Bidirectional Label Switched
              Paths (LSPs)", RFC 7551, DOI 10.17487/RFC7551, May 2015,
              <https://www.rfc-editor.org/info/rfc7551>.

   [RFC7657]  Black, D., Ed. and P. Jones, "Differentiated Services
              (Diffserv) and Real-Time Communication", RFC 7657,
              DOI 10.17487/RFC7657, November 2015,
              <https://www.rfc-editor.org/info/rfc7657>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8169]  Mirsky, G., Ruffini, S., Gray, E., Drake, J., Bryant, S.,
              and A. Vainshtein, "Residence Time Measurement in MPLS
              Networks", RFC 8169, DOI 10.17487/RFC8169, May 2017,
              <https://www.rfc-editor.org/info/rfc8169>.

   [RFC8283]  Farrel, A., Ed., Zhao, Q., Ed., Li, Z., and C. Zhou, "An
              Architecture for Use of PCE and the PCE Communication
              Protocol (PCEP) in a Network with Central Control",
              RFC 8283, DOI 10.17487/RFC8283, December 2017,
              <https://www.rfc-editor.org/info/rfc8283>.



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Authors' Addresses

   Balazs Varga (editor)
   Ericsson
   Magyar Tudosok krt. 11.
   Budapest  1117
   Hungary

   Email: balazs.a.varga@ericsson.com


   Janos Farkas
   Ericsson
   Magyar Tudosok krt. 11.
   Budapest  1117
   Hungary

   Email: janos.farkas@ericsson.com


   Andrew G. Malis
   Huawei Technologies

   Email: agmalis@gmail.com


   Stewart Bryant
   Huawei Technologies

   Email: stewart.bryant@gmail.com


   Jouni Korhonen

   Email: jouni.nospam@gmail.com
















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