[Docs] [txt|pdf] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02 03 04 05

Network Working Group                                      L. Qiang, Ed.
Internet-Draft                                                   X. Geng
Intended status: Informational                                    B. Liu
Expires: March 6, 2020                                    T. Eckert, Ed.
                                                                  Huawei
                                                                 L. Geng
                                                            China Mobile
                                                                   G. Li
                                                       September 3, 2019


                  Large-Scale Deterministic IP Network
                draft-qiang-detnet-large-scale-detnet-05

Abstract

   This document presents the overall framework and key method for
   Large-scale Deterministic Network (LDN).  LDN can provide bounded
   latency and delay variation (jitter) without requiring precise time
   synchronization among nodes, or per-flow state in transit nodes.

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 March 6, 2020.

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



Qiang, et al.             Expires March 6, 2020                 [Page 1]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   to this document.  Code Components 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
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   3
     1.2.  Terminology & Abbreviations . . . . . . . . . . . . . . .   3
   2.  Overview  . . . . . . . . . . . . . . . . . . . . . . . . . .   4
     2.1.  Summary . . . . . . . . . . . . . . . . . . . . . . . . .   4
     2.2.  Background  . . . . . . . . . . . . . . . . . . . . . . .   4
       2.2.1.  Deterministic End-to-End Latency  . . . . . . . . . .   4
       2.2.2.  Hop-by-Hop Delay  . . . . . . . . . . . . . . . . . .   4
       2.2.3.  Cyclic Forwarding . . . . . . . . . . . . . . . . . .   5
       2.2.4.  Co-Existence with Non-Deterministic Traffic . . . . .   6
     2.3.  System Components . . . . . . . . . . . . . . . . . . . .   6
   3.  LDN Forwarding Mechanism  . . . . . . . . . . . . . . . . . .   7
     3.1.  Cyclic Queues . . . . . . . . . . . . . . . . . . . . . .   8
     3.2.  Cycle Mapping . . . . . . . . . . . . . . . . . . . . . .   9
   4.  Performance Analysis  . . . . . . . . . . . . . . . . . . . .  11
     4.1.  Queueing Delay  . . . . . . . . . . . . . . . . . . . . .  11
     4.2.  Jitter  . . . . . . . . . . . . . . . . . . . . . . . . .  11
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  13
   8.  Normative References  . . . . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   This document explores the DetNet forwarding over large-scale
   network.  In contrast to TSN that deployed in LAN, DetNet is expected
   to be deployed in larger scale network that has the following
   features:

   o  a large number of network devices

   o  the distance between two network devices is long

   o  a lot of deterministic flows on the network

   These above features will bring the following challenges to DetNet
   forwarding:

   o  difficult to achieve precise time synchronization among all nodes




Qiang, et al.             Expires March 6, 2020                 [Page 2]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   o  long link propagation delay may introduce bigger jitter

   o  per-flow state is un-scalable

   Motivated by these challenges, this document presents a Large-scale
   Deterministic Network (LDN) mechanism.  As
   [draft-ietf-detnet-problem-statement] indicates, deterministic
   forwarding can only apply on flows with well-defined traffic
   characteristics.  The traffic characteristics of DetNet flow has been
   discussed in [draft-ietf-detnet-architecture], that could be achieved
   through shaping at Ingress node or up-front commitment by
   application.  LDN assumes that DetNet flows follow some specific
   traffic patterns accordingly.

1.1.  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.

1.2.  Terminology & Abbreviations

   This document uses the terminology defined in
   [draft-ietf-detnet-architecture].

   TSN: Time Sensitive Network

   PQ: Priority Queuing

   CQF: Cyclic Queuing and Forwarding

   LDN: Large-scale Deterministic Network

   DSCP: Differentiated Services Code Point

   EXP: Experimental

   TC: Traffic Class

   T: the length of a cycle

   H: the number of hops







Qiang, et al.             Expires March 6, 2020                 [Page 3]


Internet-Draft      Large-Scale Deterministic Network     September 2019


2.  Overview

2.1.  Summary

   In LDN, nodes (network devices) have synchronized frequency, and each
   node forwards packets in a slotted fashion based on a cycle
   identifiers carried in packets.  Ingres nodes or senders have a
   function called gate to shape/condition traffic flows.  Except for
   this gate function, the LDN has no awareness of individual flows.

2.2.  Background

   This section motivates the design choices taken by the proposed
   solution and gives the necessary background for deterministic delay
   based forwarding plane designs.

2.2.1.  Deterministic End-to-End Latency

   Bounded delay is delay that has a deterministic upper and lower
   bound.

   The delay for packets that need to be forwarded with deterministic
   delay needs to be deterministic on every hop.  If any hop in the
   network introduces non-deterministic delay, then the network itself
   can not deliver a deterministic delay service anymore.

2.2.2.  Hop-by-Hop Delay

   Consider a simple example shown in Figure 1, where Node X has 10
   receiving interfaces and one outgoing interface I all of the same
   speed.  There are 10 deterministic traffic flows, each consuming 5%
   of a links bandwidth, one from each receiving interface to the
   outgoing interface.

   Node X sends 'only' 50% deterministic traffic to interface I, so
   there is no ongoing congestion, but there is added delay.  If the
   arrival time of packets for these 10 flows into X is uncontrolled,
   then the worst case is for them to all arrive at the same time.  One
   packet has to wait in X until the other 9 packets are sent out on I,
   resulting in a worst case deterministic delay of 9 packets
   serialization time.  On the next hop node Y downstream from X, this
   problem can become worse.  Assume Y has 10 upstream nodes like X, the
   worst case simultaneous burst of packets is now 100 packets, or a 99
   packet serialization delay as the worst case upper bounded delay
   incurred on this hop.

   To avoid the problem of high upper bound end-to-end delay, traffic
   needs to be conditioned/interleaved on every hop.  This allows to



Qiang, et al.             Expires March 6, 2020                 [Page 4]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   create solutions where the per-hop-delay is bounded purely by the
   physics of the forwarding plane across the node, but not the
   accumulated characteristics of prior hop traffic profiles.

              +--+  +--+      ---                      ---
              |A1|  |A0|     -   -                    -   -
              +--+  +--+    -     -                  -     -
          ---------------->-       -                -       -
            +--+    +--+   -       -                -       -
            |B1|    |B0|   -       -                -       -
            +--+    +--+   -       -Interface I     -       -
          ---------------->-Node X ---------------> -Node Y ----->
                +--++--+   -       -                -       -
                |C1||C0|   -                        -
                +--++--+   -       -                -       -
          ---------------->-       -                -       -
                    .      -       -                -       -
                    .       -     -                  -     -
                    .        -   -                    -   -
                              ---                      ---

              Figure 1: Micro-burst and micro-burst iteration

2.2.3.  Cyclic Forwarding

   The common approach to solve that problem is that of a cyclic hop-by-
   hop forwarding mechanism.  Assume packets forwarded from N1 via N2 to
   N3 as shown in Figure 2.  When N1 sends a packet P to interface I1
   with a Cycle X, it must be guaranteed by the forwarding mechanism
   that N2 will forward P via I2 to N3 in a cycle Y.

   The cycle of a packet can either be deduced by a receiving node from
   the exact time it was received as is done in SDN/TDMA systems, and/or
   it can be indicated in the packet.  This document solution relies on
   such markings because they allow to reduce the need for synchronous
   hop-by-hop transmission timings of packets.

   In a packet marking based slotted forwarding model, node N1 needs to
   send packets for cycle X before the latest possible time that will
   allow for N2 to further forward it in cycle Y to N3.  Because of the
   marking, N1 could even transmit packets for cycle X before all
   packets for the previous cycle (X-1) have been sent, reducing the
   synchronization requirements between across nodes.








Qiang, et al.             Expires March 6, 2020                 [Page 5]


Internet-Draft      Large-Scale Deterministic Network     September 2019


                 P sent in          P sent in         P sent in
                cycle(N1,I1,X)    cycle(N2,I2,Y)     cycle(N3,I3,Z)
                +--------+        +--------+         +--------+
                | Node N1|------->| Node N2|-------->| Node N3|------>
                +--------+I1      +--------+I2       +--------+I3

                        Figure 2: Cyclic Forwarding

2.2.4.  Co-Existence with Non-Deterministic Traffic

   Traffic with deterministic delay requirements can co-exist with
   traffic only requiring non-deterministic delay by using packet
   scheduling where the delay incurred by non-deterministic packets is
   deterministic for the deterministic traffic (and low).  If LDN is
   deployed together with such non-deterministic delay traffic than such
   a scheme must be supported by the forwarding plane.  A simple
   approach for the delay incurred on the sending interface of a
   deterministic node due to non-deterministic traffic is to serve
   deterministic traffic via a strict, highest-priority queue and
   include the worst case delay of a currently serialized non-
   deterministic packet into the deterministic delay budget of the node.
   Similar considerations apply to the internal processing delays in a
   node.

2.3.  System Components

   The Figure 3 shows an overview of the components considered in this
   document system and how they interact.

   A network topology of nodes, Ingress, Core and Egress support a
   method for cyclic forwarding to enable LDN.  This forwarding requires
   no per-flow state on the nodes, and tolerates loss time
   synchronization.

   Ingress edge nodes may support the (G)ate function to shape traffic
   from sources into the desired traffic characteristics, unless the
   source itself has such function.  Per-flow state is required on the
   ingress edge node.  LDN should work with some resource reservation
   methods, that will be not discussed in this document.












Qiang, et al.             Expires March 6, 2020                 [Page 6]


Internet-Draft      Large-Scale Deterministic Network     September 2019


        /--\.     +--+        +--+      +--+        +--+.     /--\
       | (G)+-----+GS+--------+ S+------+ S+--------+ S+-----+    |
        \--/      +--+        +--+      +--+        +--+      \--/

       Sender    Ingress      Core      Core       Egress   Receiver
                Edge Node     Node      Node     Edge Node


                         Figure 3: Overview of LDN

3.  LDN Forwarding Mechanism

   DetNet aims at providing deterministic service over large scale
   network.  In such large scale network, it is difficulty to get
   precise time synchronization among numerous devices.  To reduce
   requirements, the forwarding mechanism described in this document
   assumes only frequency synchronization but not time synchronization
   across nodes: nodes maintain the same clock frequency 1/T, but do not
   require the same time as shown in Figure 4.

         <-----T----->                       <-----T----->
         |           |           |           |           |           |
 Node A  +-----------+-----------+   Node A  +-----------+-----------+
                     T0                                  T0

         |           |           |              |           |           |
 Node B  +-----------+-----------+   Node B     +-----------+-----------+
                     T0                                     T0

     (i) time synchronization           (ii) frequency synchronization

     T: length of a cycle
     T0: timestamp

        Figure 4: Time Synchronization & Frequency Synchronization

   IEEE 802.1 CQF is an efficient forwarding mechanism in TSN that
   guarantees bounded end-to-end latency.  CQF is designed for limited
   scale networks.  Time synchronization is required, and the link
   propagation delay is required to be smaller than a cycle length T.
   Considering the large scale network deployment, the proposed LDN
   Forwarding mechanism permits frequency synchronization and link
   propagation delay may exceed T.  Besides these two points, CQF and
   the asynchronous forwarding of LDN are very similar.

   Figure 5 compares CQF and LDN through an example.  Suppose Node A is
   the upstream node of Node B.  In CQF, packets sent from Node A at




Qiang, et al.             Expires March 6, 2020                 [Page 7]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   cycle x, will be received by Node B at the same cycle, then further
   be sent to downstream node by Node B at cycle x+1.

   In LDN, due to long link propagation delay and frequency
   synchronization, Node B will receive packets from Node A at different
   cycle denoted by y, then re-send out at cycle y+1.  The cycle mapping
   relationship (e.g., x->y+1) exists between any pair of neighbor
   nodes.  With this kind of cycle mapping, the receiving node can
   easily figure out when the received packets should be sent out, the
   only requirement is to carry the cycle identifier of sending node in
   the packets.

       |  cycle x  | cycle x+1 |          |  cycle x  | cycle x+1 |
Node A +-----------+-----------+   Node A +-----------+-----------+
          \                                           \
           \packet                                      \packet
            \receiving                                   \receiving
             \                                            \
       |      V    | cycle x+1 |                 |         V |  cycle y+1|
Node B +-----------+-----------+      Node B     +-----------+-----------+
          cycle x      \packets                     cycle y      \packets
                        \sending                                  \sending
                         \                                         \
                          \                                         \
                           V                                         V

              (i) CQF                                (ii) LDN


                            Figure 5: CQF & LDN

3.1.  Cyclic Queues

   In CQF each port needs to maintain 2 (or 3) queues, one receiving
   queue is used to buffer newly received packets, one sending queue is
   used to store the packets that are going to be sent out, one more
   queue may be needed to avoid output starvation [scheduled-queues].

   In LDN, at least 3 cyclic queues (2 receiving queues and 1 sending
   queue) are maintained for each port on a node.  A cyclic queue
   corresponds to a cycle.  As Figure 6 illustrated, the downstream Node
   B may receive packets sent at two different cycles from Node A due to
   the absence of time synchronization.  Following the cycle mapping
   (i.e., x --> y+1), packets that carry cycle identifier x should be
   sent out by Node B at cycle y+1, and packets that carry cycle
   identifier x+1 should be sent out by Node B at cycle y+2.  Therefore,
   2 receiving queues are needed to store the received packets, one is
   for the packets that carry cycle identifier x, another one is for the



Qiang, et al.             Expires March 6, 2020                 [Page 8]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   packets that carry cycle identifier x+1.  Plus one sending queue,
   each port needs at least 3 cyclic queues in LDN.  In order to absorb
   more link delay variation (such as on radio interface), more queues
   may be necessary.

                         |  cycle x  | cycle x+1 |
                 Node A  +-----------+-----------+
                                  \      \
                                   \      \packet
                                    \      \receiving
                                   | V      V  |           |
                        Node B     +-----------+-----------+
                                      cycle y    cycle y+1


       Figure 6: An example illustrates for 2 receiving queue in LDN

3.2.  Cycle Mapping

   The cycle mapping relationship (e.g., x->y+1) exists between any pair
   of neighbor nodes, that could be configured through control plane or
   self-studied in data plane.  As Figure 7 shows, the cycle mapping
   relationship instructs the packet forwarding in two modes -- swap
   mode or stack mode.

   o  In swap mode, node stores the cycle mapping relationship locally.
      After receiving a packet carrying a cycle identifier, the node
      will check its cycle mapping relationship table, swap the cycle
      identifier with a new cycle identifier, then put the packet into
      an appropriate queue.  A path with dedicated resource needs to be
      established first, then packet is forwarded along the path in swap
      mode.

   o  In stack mode, a central controller computes the cycle identifier
      of every node, which ensures that there is no flow confliction
      along the path and satisfies the end-to-end latency requirement.
      The cycle identifiers are encapsulated into the packet in the
      ingress.  No other status information needs to be maintained in
      the intermediate nodes.












Qiang, et al.             Expires March 6, 2020                 [Page 9]


Internet-Draft      Large-Scale Deterministic Network     September 2019


             LDN Packet
           +------+---+  +-----------------------+ +------+---+
           |      | x |  |                       | |      |y+1|
           +------+---+  |    Swap Mode Node     | +------+---+
             ----------->|                       |----------->
                         |       (x->y+1)        |
                         |                       |
                         +-----------------------+


            LDN Packet
       +------+---=====   +-----------------------+ +------=====---+
       |      |y+1= x =   |                       | |      =y+1= x |
       +------+---=====   |                       | +------=====---+
              ----------->|    Stack Mode Node    |----------->
                          |                       |
                          |                       |
                          +-----------------------+

             =====
             =   =  Current Cycle Identifier
             =====


                            Figure 7: Two Modes

   As section 3.1 illustrates, there are 3 (or 4) different queues at
   each port.  Therefore, the cycle identifier should be able to express
   3 (or 4) different values, each value corresponds to a queue.  That
   means minimal 2 bits are needed to identify different cycles between
   a pair of neighboring nodes.  This document does not yet aim to
   propose one, but gives an (incomplete) list of ideas:

   o  DSCP of IPv4 Header

   o  Traffic Class of IPv6 Header

   o  TC of MPLS Header (used to be EXP)

   o  IPv6 Extension Header

   o  UDP Option

   o  SID of SRv6

   o  Reserved of SRH

   o  TLV of SRv6



Qiang, et al.             Expires March 6, 2020                [Page 10]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   o  TC of SR-MPLS Header (used to be EXP)

   o  3 (or 4) labels/adjacency SIDs for SR-MPLS

4.  Performance Analysis

4.1.  Queueing Delay

   Figure 8 describes one-hop packet forwarding delay, that mainly
   consisted of A->B link propagation delay and queuing delay in Node B.

                        |cycle x |
                 Node A +-------\+
                                 \
                                  \
                                   \
                                   |\ cycle y|cycle y+1|
                 Node B            +V--------+--------\+
                                   :                   \
                                   :   Queueing Delay  :\
                                   :...=2*T ............ V


                    Figure 8: Single-Hop Queueing Delay

   As Figure 8 shows, cycle x of Node A will be mapped into cycle y+1 of
   Node B as long as the last packet sent from A->B is received within
   the cycle y.  If the last packet is re-sent out by B at the end of
   cycle y+1, then the largest single-hop queueing delay is 2*T.
   Therefore the end-to-end queueing delay's upper bound is 2*T*H, where
   H is the number of hops.

   If A did not forward the LDN packet from a prior LDN forwarder but is
   the actual traffic source, then the packet may have been delayed by a
   gate function before it was sent to B.  The delay of this function is
   outside of scope for the LDN delay considerations.  If B is not
   forwarding the LDN packet but the final receiver, then the packet may
   not need to be queued and released in the same fashion to the
   receiver as it would be queued/released to a downstream LDN node, so
   if a path has one source followed by N LDN forwarders followed by one
   receivers, this should be considered to be a path with N-1 LDN hops
   for the purpose of latency and jitter calculations.

4.2.  Jitter

   Considering the simplest scenario one hop forwarding at first,
   suppose Node A is the upstream node of Node B, the packet sent from




Qiang, et al.             Expires March 6, 2020                [Page 11]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   Node A at cycle x will be received by Node B at cycle y as Figure 9
   shows.

      - The best situation is Node A sends packet at the end of cycle x,
      and Node B receives packet at the beginning of cycle y, then the
      delay is denoted by w;

      - The worst situation is Node A sends packet at the beginning of
      cycle x, and Node B receives packet at the end of cycle y, then
      the delay= w + length of cycle x + length of cycle y= w+2*T;

      - Hence the jitter's upper bound of this simplest scenario= worst
      case-best case=2*T.

             |cycle x |                        |cycle x |
      Node A +-------\+                 Node A +\-------+
                     :\                           \     :
                     : \                           -------------\
                     :  \                               :        \
                     :w |\        |                     :w|       \ |
      Node B         :  +V--------+     Node B          : +--------V+
                          cycle y                           cycle y

          (a) best situation               (b) worst situation


             Figure 9: Jitter Analysis for One Hop Forwarding

   Next considering two hops forwarding as Figure 10 shows.

      - The best situation is Node A sends packet at the end of cycle x,
      and Node C receives packet at the beginning of cycle z, then the
      delay is denoted by w';

      - The worst situation is Node A sends packet at the beginning of
      cycle x, and Node C receives packet at the end of cycle z, then
      the delay= w' + length of cycle x + length of cycle z= w'+2*T;

      - Hence the jitter's upper bound = worst case-best case=2*T.












Qiang, et al.             Expires March 6, 2020                [Page 12]


Internet-Draft      Large-Scale Deterministic Network     September 2019


                        |cycle x |
                 Node A +-------\+
                                 \
                                 :\| cycle y |
                 Node B          : \---------+
                                 :  \
                                 :   \--------\
                                 :             \         |
                 Node C          ......w'......+V--------+
                                                 cycle z

                            (a) best situation


                         |cycle x |
                  Node A +\-------+
                           \      :
                            \     : | cycle y |
                  Node B     \    : +---------+
                              \   :
                               ---:--------------------\
                                  :             |       \ |
                  Node C          :......w'.....+--------V+
                                                  cycle z

                             (b) worst situation


            Figure 10: Jitter Analysis for Two Hops Forwarding

   And so on.  For multi-hop forwarding, the end-to-end delay will
   increase as the number of hops increases, while the delay variation
   (jitter) still does not exceed 2*T.

5.  IANA Considerations

   This document makes no request of IANA.

6.  Security Considerations

   Security issues have been carefully considered in
   [draft-ietf-detnet-security].  More discussion is TBD.

7.  Acknowledgements

   TBD.





Qiang, et al.             Expires March 6, 2020                [Page 13]


Internet-Draft      Large-Scale Deterministic Network     September 2019


8.  Normative References

   [draft-ietf-detnet-architecture]
              "DetNet Architecture", <https://datatracker.ietf.org/doc/
              draft-ietf-detnet-architecture/>.

   [draft-ietf-detnet-dp-sol]
              "DetNet Data Plane Encapsulation",
              <https://datatracker.ietf.org/doc/
              draft-ietf-detnet-dp-sol/>.

   [draft-ietf-detnet-problem-statement]
              "DetNet Problem Statement",
              <https://datatracker.ietf.org/doc/
              draft-ietf-detnet-problem-statement/>.

   [draft-ietf-detnet-security]
              "DetNet Security Considerations",
              <https://datatracker.ietf.org/doc/
              draft-ietf-detnet-security/>.

   [draft-ietf-detnet-use-cases]
              "DetNet Use Cases", <https://datatracker.ietf.org/doc/
              draft-ietf-detnet-use-cases/>.

   [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>.

   [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>.

   [scheduled-queues]
              "Scheduled queues, UBS, CQF, and Input Gates",
              <http://www.ieee802.org/1/files/public/docs2015/
              new-nfinn-input-gates-0115-v04.pdf>.

Authors' Addresses

   Li Qiang (editor)
   Huawei
   Beijing
   China

   Email: qiangli3@huawei.com




Qiang, et al.             Expires March 6, 2020                [Page 14]


Internet-Draft      Large-Scale Deterministic Network     September 2019


   Xuesong Geng
   Huawei
   Beijing
   China

   Email: gengxuesong@huawei.com


   Bingyang Liu
   Huawei
   Beijing
   China

   Email: liubingyang@huawei.com


   Toerless Eckert (editor)
   Huawei USA - Futurewei Technologies Inc.
   2330 Central Expy
   Santa Clara  95050
   USA

   Email: tte+ietf@cs.fau.de


   Liang Geng
   China Mobile
   Beijing
   China

   Email: gengliang@chinamobile.com


   Guangpeng Li

















Qiang, et al.             Expires March 6, 2020                [Page 15]


Html markup produced by rfcmarkup 1.129c, available from https://tools.ietf.org/tools/rfcmarkup/