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Versions: 00

Network Working Group                                      D. Dukes, Ed.
Internet-Draft                                               C. Filsfils
Intended status: Standards Track                                G. Dawra
Expires: April 29, 2018                                     P. Camarillo
                                                                 F. Clad
                                                           Cisco Systems
                                                              S. Salsano
                                               Univ. of Rome Tor Vergata
                                                        October 26, 2017


                  SR For SDWAN: VPN with Underlay SLA
                    draft-dukes-sr-for-sdwan-00.txt

Abstract

   This document describes how SR enables underlay Service Level
   Agreements (SLA) to a VPN with scale and security while ensuring
   service opacity.  This solution applies to Over-The-Top VPN (OTT VPN)
   and Software-Defined WAN (SDWAN).

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 April 29, 2018.

Copyright Notice

   Copyright (c) 2017 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



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   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
   2.  Requirements Notation . . . . . . . . . . . . . . . . . . . .   3
   3.  Single Provider . . . . . . . . . . . . . . . . . . . . . . .   3
     3.1.  Directly Connected CE to PE . . . . . . . . . . . . . . .   3
     3.2.  Best-effort Underlay Transport  . . . . . . . . . . . . .   5
     3.3.  SR for Underlay SLA Differentiation . . . . . . . . . . .   6
     3.4.  Accounting  . . . . . . . . . . . . . . . . . . . . . . .   8
     3.5.  Security  . . . . . . . . . . . . . . . . . . . . . . . .   8
     3.6.  Remotely Connected (to PE)  . . . . . . . . . . . . . . .   8
   4.  Multiple Providers  . . . . . . . . . . . . . . . . . . . . .   8
   5.  Control Plane . . . . . . . . . . . . . . . . . . . . . . . .   9
   6.  Benefits  . . . . . . . . . . . . . . . . . . . . . . . . . .  11
     6.1.  Scale . . . . . . . . . . . . . . . . . . . . . . . . . .  11
     6.2.  Privacy . . . . . . . . . . . . . . . . . . . . . . . . .  12
     6.3.  Flexible Billing  . . . . . . . . . . . . . . . . . . . .  12
     6.4.  Security  . . . . . . . . . . . . . . . . . . . . . . . .  12
   7.  Appendix  . . . . . . . . . . . . . . . . . . . . . . . . . .  12
     7.1.  Single Provider Example Using End.BM With an MPLS Core  .  12
     7.2.  Single Provider Example Using MPLS From CE to PE for BSID  12
     7.3.  Single Provider Example Using SRMPLS Over UDP For CE to
           PE Not Directly Connected Over Internet . . . . . . . . .  12
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     10.1.  Informative References . . . . . . . . . . . . . . . . .  13
     10.2.  Normative References'  . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   This document describes how SR enables underlay SLA to a VPN with
   scale and security while ensuring service opacity.  This solution
   applies to Over-The-Top VPN (OTT VPN) with SLA differentiation, and
   Software-Defined WAN (SDWAN) with SLA differentiation.

   The body of this text uses SRv6 for illustration.  A similar solution
   leveraging SR-MPLS is illustrated in an appendix.

   This document assumes familiarity with the following IETF documents:

   o  Segment Routing Architecture [I-D.ietf-spring-segment-routing]



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   o  Segment Routing with MPLS data plane
      [I-D.ietf-spring-segment-routing-mpls]

   o  IPv6 Segment Routing Header [I-D.ietf-6man-segment-routing-header]

   o  SRv6 Network Programming
      [I-D.filsfils-spring-srv6-network-programming]

   o  Segment Routing Policy For Traffic Engineering
      [I-D.filsfils-spring-segment-routing-policy]

   o  IS-IS Extensions to Support Segment Routing over IPv6 Dataplane
      [I-D.bashandy-isis-srv6-extensions]

   For clarity, this version of the document uses the SDWAN example with
   SRv6 to illustrate how SR can be used to provide underlay SLA to
   overlay services.  The journey of a packet from the left site to the
   right site of the SDWAN Overlay is described.  The solution applies
   similarly for the return path.

2.  Requirements Notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

3.  Single Provider

3.1.  Directly Connected CE to PE






















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   +------------+                                       /-----------/
   |   SDWAN    |                                      /           /
   |  Control   |                                     / [SDWAN-C]...
   +------------+                                    /           / :
                                                    /-----------/  :
                                                                   :
                  /-------------------------------------------/    :
   +---------+   /                                           /     :
   |  SDWAN  |  /    [A]-----[E1]***********[E2]--------[Z] /      :
   | Overlay | /               :              :            /       :
   +---------+/                :......        :           /        :
             /-----------------------:--------:----------/         :
                                     :        :                    :
                                     :        :                    :
                      /----------/   :        :                    :
   +------------+    /          /    :        :                    :
   |     SP     |   /  [SR-C]  /     :        :                    :
   |  Control   |  /     :    /      :        :                    :
   +------------+ /------:---/   ....:        ..                   :
                         :       :             :                   :
                         :       :             :                   :
   +------------+        :   /---:-------------:-------------/     :
   |     SP     |        :  /    :             :            /      :
   |  Underlay  |        : /   [C1]----------[C2]          /       :
   +------------+        :/       \           /           /        :
                         :         \      /--/           /         :
                        /:          \    /              /          :
                       / :...........[C3]..........................:
                      /                               /
                     /-------------------------------/

   **** = logical connection
   :... = physical connection, between layers
   /--\ = physical connection, within a layer

                     Figure 1: SDWAN Reference Diagram

   An SDWAN overlay is composed of two sites A and Z, connected to the
   Internet via edge nodes E1 and E2 respectively.  E1 and E2 (customer
   edge nodes) are connected via a Service Provider (SP) underlay to
   form the VPN between the sites.

   C1, C2 and C3 are nodes of the SP underlay, where C1 and C2 are
   Provider Edge nodes.  ISIS is deployed in the SP underlay with the
   same cost on each link.

   E1 and E2 connect to C1 and C2 respectively.  The shortest path from
   C1 to C2 is the best-effort path.  The explicit path C1-C3-C2 is the



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   low-latency path.  By default, traffic transported from C1 to C2
   follows the best-effort path.  By default, an SDWAN cannot benefit
   from the low-latency path from C1 to C2.

   The address of A is 10.10.0.10/32 and the address of Z is
   10.26.0.26/32.  E1 and E2 respectively advertise 10.10/16 and
   10.26/16 to the SDWAN controller SDWAN-C via a secure channel over
   the Internet.  The solution is applicable to any traffic exchanged
   between the sites, including IPv4, IPv6 or L2.  For clarity, a single
   example with IPv4 in the SDWAN Overlay is used.

   The SP operates an SR controller SR-C capable of computing
   constrained paths from C1 to C2.

3.2.  Best-effort Underlay Transport

   Let's consider the path taken by traffic from A to Z, across the
   SDWAN, between nodes E1 and E2 with addresses E1:: and E2::
   respectively.

   Host A sends a packet P to Z via E1.  Packet P has source address
   10.10.0.10 and destination address 10.26.0.26, illustrated as P
   (10.10.0.10,10.26.0.26)(payload).  E1, upon receipt of P, determines
   E2 is the edge node to be used to reach Z.  Edge node E1 encrypts,
   encapsulates and forwards the packet P toward E2 and Z, and it is
   handled as follow:

   o  Between A and E1 : P (10.10.0.10,10.26.0.26)(Payload)

   o  Between E1 and C1 : P
      (E1::,E2::,NH=ESP)(NH=IPv4,(10.10.0.10,10.26.0.26)(Payload))

      *  Note that ESP tunnel mode encapsulation, encryption and
         authentication is assumed but not required.

   o  Between C1 and C2 : P
      (E1::,E2::,NH=ESP)(NH=IPv4,(10.10.0.10,10.26.0.26)(Payload))

   o  Between C2 and E2 : P (E1::,E2::,NH=ESP)(
      NH=IPv4,(10.10.0.10,10.26.0.26)(Payload))

   o  Between E2 and Z : P (10.10.0.10,10.26.0.26)(Payload)

   This example illustrates that, classically (i.e., without the SR
   solution described in this document), the SDWAN cannot leverage the
   rich infrastructure of the SP to meet its needs.  The SP is
   constrained to offer best-effort transit which does not reflect the
   capabilities of its infrastructure.



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3.3.  SR for Underlay SLA Differentiation

   SR enables the SDWAN to steer selected flows through selected
   transport paths of the SP, using the same example in Figure 1.

   This small example, with only 3 SP routers, assumes all three support
   SRv6.  As explained in
   [I-D.filsfils-spring-srv6-network-programming], a typical deployment
   would only require SRv6 at a few strategic waypoints deployed through
   the network.

   It also assumes ISIS supports the lightweight SRv6 extension
   described in [I-D.bashandy-isis-srv6-extensions].

   The illustration convention from
   [I-D.filsfils-spring-srv6-network-programming] is used such that:

   o  SRv6 SID Cj:: is explicitly instantiated at node Cj and bound to
      the END.PSP function.

   o  SRv6 SID C1::B21 is a Binding SID (BSID) explicitly instantiated
      at headend C1 and bound to the SRTE policy <C3::, C2::> towards
      endpoint C2.

      *  Note the return direction would use a BSID C2::B11, bound at
         headend C2, to the SRTE policy <C3::, C1::> towards endpoint
         C1.

   The Control-Plane (CP) workflow that leads to the instantiation of
   this Binding SID will be explained in the Control-Plane section.

   Let's again consider the path from A to Z for a packet P, but this
   time E1 has been configured by SDWAN-C to steer packet P into a
   preferred low-latency path of the SP bound to the binding SID C1:B21.

   o  Between A and E1

      *  P (10.10.0.10,10.26.0.26)(payload)

   o  Between E1 and C1

      *  P (E1::,C1::B21; NH=SRH)(E2::,C1::B21; SL=1;
         NH=ESP)(NH=IPv4(10.10.0.10,10.26.0.26)(Payload))

   When the Binding SID C1::B21 is processed at C1, the SR TE Policy is
   selected and the SRH for SID list <C3::,C2::> is inserted into P:

   o  Between C1 and C3



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      *  P (E1::,C3::;NH=SRH)(E2::,C2::,C3::; SL=2;NH=ESP)
         (NH=IPv4(10.10.0.10,10.26.0.26)(Payload))

   At C3, the SegmentsLeft is decremented as the END SID C3:: is
   processed, and C2:: is placed in the destination address:

   o  Between C3 and C2

      *  P (E1::,C2::;NH=SRH)(E2::,C2::,C3::; SL=1;NH=ESP)
         (NH=IPv4(10.10.0.10,10.26.0.26)(Payload))

   At C2, the SegmentsLeft is decremented to 0, and penultimate segment
   pop is applied as the END SID C2:: is processed and E2:: is placed in
   the destination address while the SRH is removed:

   o  Between C2 and E2

      *  P (E1::,E2::,NH=ESP)(NH=IPv4(10.10.0.10,10.26.0.26)(Payload))

   Finally, E2 decrypts the packet and strips the outer header to
   forward the original packet to Z:

   o  Between E2 and Z

      *  P (10.10.0.10,10.26.0.26)(Payload)

   The SDWAN edge nodes (E1,E2) maintain their existing behavior of

   o  Ingress Edge Node: classify ingress traffic, determining the
      egress edge node, selecting a local output interface, secure the
      traffic, and forward to the chosen egress edge node.

   o  Egress Edge Node: decapsulate, decrypt and forward on the internal
      network.

   The only change is that the Ingress node now monitors and selects an
   SRv6 binding SID then pushes an SRH with two SIDs.

   Note as well that the ingress and egress edge nodes never see the
   actual SID list used by the SP to deliver the preferred path.  A
   variation of this design allows for the BSID to be kept in the packet
   so that the egress node can detect which packets have been steered on
   which preferred path (for accounting or monitoring purposes).

   This is a fairly simple example of how SRv6 binding SIDs and SR TE
   policies may be used to provide multiple diverse paths for SDWAN
   traffic traversing a single provider network.




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3.4.  Accounting

   As per SRv6 network programming
   [I-D.filsfils-spring-srv6-network-programming], each SRTE policy and
   its bound BSID is associated with a unique traffic counter.  This
   allows the SP to implement various forms of billing and reporting to
   the customer of the preferred path.

3.5.  Security

   The domain of trust security solution documented in
   [I-D.filsfils-spring-srv6-network-programming] is utilized.

   Specifically SEC1, SEC2 and SEC3 guarantee that external traffic to
   the SP cannot exercise the SID's of the SP.

   The following behavior is added: the ACL implementing SEC1 and SEC2
   on node C1 is updated to specifically allow traffic from E1:: to
   C1::B21.

   Only the SDWAN edge that has ordered the preferential service can use
   it.

   Any other customer of the SP is unable to use the preferential path
   bound to BSID C1::B21.

   The SDWAN site that has ordered the preferential service is unable to
   directly program the network of the SP using the internal SID's of
   the SP.  The SDWAN edge node is restricted to the BSID, which
   opacifies the SP operation.

3.6.  Remotely Connected (to PE)

   Well known authentication technology with details provided in
   subsequent revisions will be added, detailing the scenario with SDWAN
   edge nodes not directly connected to the SP node terminating the
   binding SID.

4.  Multiple Providers

   Well known authentication technology with details provided in
   subsequent revisions will be added, detailing the scenario with SDWAN
   edge nodes connected to the SP node offering binding SID via an
   intermediate SP.







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5.  Control Plane

   The SDWAN overlay in Figure 1 is managed by an SDWAN controller,
   SDWAN-C.

   The control protocols used by the SDWAN-C to signal the site routes,
   the BSID's and the site policies (which traffic on which BSID when)
   securely over the SP network to E1 and E2 is outside the scope of
   this document.

   The SP underlay operates its internal SR deployment with an SR
   controller (SR-C).  SR-C interacts with the SP's network (Cj) through
   standardized protocols (PCE[RFC4674] , PCEP [RFC5440]/[RFC4657], BGP
   RR[RFC4456], BGP-TE [I-D.ietf-idr-segment-routing-te-policy], BGP-LS
   [RFC7752])

   Most likely, the SP would operate its underlay SLA service with a
   service controller (SERV-C) that is separate from SR-C.  To simplify
   the illustration, this text assumes that SERV-C and SR-C are
   integrated.

   This section describes the high-level interaction between these
   controllers for the low-latency use-case described in this document,
   where an enterprise operator installs a policy in the SDWAN-C
   requiring a low latency service between E1 and E2.


























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       +----------+
       |Enterprise|
       | Operator |
       +----------+
   +---+    |        +----------+   +-------+       +---+
   |E1 |    |        | SDWAN-C  |   | SR-C  |       |C1 |
   +---+    |        +----------+   +-------+       +---+
     |      |              |            |             |
     |      |-------i----->|            |             |
     |      |Require low   |            |             |
     |      |latency from  |            |             |
     |      |E1 to E2 for  |            |             |
     |      |some traffic  |            |             |
     |      |              +------ii---->             |
     |      |           request service |----+        |
     |      |           from E1:: to    |  iii        |
     |      |           E2:: for low    |<---+        |
     |      |           latency         |Compute an SR|
     |      |              |            |Policy for E1|
     |                     |            |to E2        |
     |                     |            |             |
     |                     |            |-----iv----->|
     |                     |            | Program SR TE
     |                     |            | Policy      |
     |                     |            |             |
     |                     |            |<-----v------+
     |                     |<----vi-----| Report policy
     |                     |reply with  | installed   |
     |                     |binding SID |             |
     |<-------vii----------|C1:B21::
     | Notify              |
     | SID C1:B21::        |
     | for low latency
     | E1:: to E2::
     |

                        Figure 2: Controlplane Flow

   (i)     The enterprise operator requests a low-latency path from site
           E1 to site E2.  It defines which traffic needs to be steered
           on this preferred path.

   (ii)    SDWAN-C requests a low-latency service from SR-C for the
           public address of E1 to the public address of E2.

   (iii)   SR-C computes an SR Policy to satisfy SDWAN-C's request:





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           A.  SR-C maps the E1 and E2 addresses to its managed nodes C1
               and C2.

           B.  SR-C statefully registers the SRTE policy from C1 to C2
               for low-latency.

           C.  SR-C computes the SID list fulfilling the SLA requirement
               (e.g. <C3::, C2::>).  The stateful nature of the SRTE
               policy ensures that the SID list is updated whenever
               required due to network state change.

           D.  SR-C binds a stable Binding SID C1::B21 to the SRTE
               policy.

   (iv)    SR-C programs C1 with the computed SRTE policy and the
           selected BSID.  Standardized protocols such as
           [I-D.ietf-idr-segment-routing-te-policy] or [RFC5440] are
           used.

   (v)     C1 installs the policy in its dataplane and reports the
           status of the SRTE policy to SR-C using standardized
           protocols [RFC7752] or [RFC5440] and
           [I-D.negi-pce-segment-routing-ipv6].

   (vi)    SR-C replies to SDWAN-C with BSID C1::B21

   (vii)   SDWAN-C programs E1 with the flow classification and steering
           policy to insert SRv6 SID C1::B21 on the appropriate traffic

6.  Benefits

6.1.  Scale

   The SP network does not hold any per-SDWAN-flow state in the core of
   its network.

   The SP network does not hold any complex L3-L7 flow classification at
   the edge of its network.

   The SP network is unaware of any policy change of the SDWAN instance
   either in terms of which flow to classify, when to steer it and on
   which path.

   The SP's role only consists in statefully maintaining SRTE policies
   at the edge of the network and maintaining a few 100's of SID's
   inside its core network.  This is the stateless property of Segment
   Routing.




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6.2.  Privacy

   The SP network does not share any information of its infrastructure,
   topology, capacity, internal SID's.

   The SDWAN instance does not share any information on its traffic
   classification, steering policy and business logic.

6.3.  Flexible Billing

   The traffic destined to a BSID is individually accounted
   [I-D.filsfils-spring-srv6-network-programming].

   The SP and SDWAN instance can agree on various forms of billing for
   the usage of the preferential path.

6.4.  Security

   By default, the SP's SR infrastructure is protected by the simple
   domain of trust solution documented in
   [I-D.filsfils-spring-srv6-network-programming].

   A BSID (and the related preferential path) can only be accessed by
   the specific SDWAN instance (and site) that ordered the service.

   The security solution supports any SDWAN site connection type:
   directly connected to the SP edge or not.

7.  Appendix

7.1.  Single Provider Example Using End.BM With an MPLS Core

   To be completed in future revisions

7.2.  Single Provider Example Using MPLS From CE to PE for BSID

   To be completed in future revisions

7.3.  Single Provider Example Using SRMPLS Over UDP For CE to PE Not
      Directly Connected Over Internet

   To be completed in future revisions

8.  IANA Considerations

   No current considerations.





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9.  Security Considerations

   A domain of trust is secured via methods documented in
   [I-D.filsfils-spring-srv6-network-programming]

10.  References

10.1.  Informative References

   [I-D.bashandy-isis-srv6-extensions]
              Ginsberg, L., Bashandy, A., Filsfils, C., and B. Decraene,
              "IS-IS Extensions to Support Routing over IPv6 Dataplane",
              draft-bashandy-isis-srv6-extensions-01 (work in progress),
              September 2017.

   [I-D.filsfils-spring-segment-routing-policy]
              Filsfils, C., Sivabalan, S., Raza, K., Liste, J., Clad,
              F., Lin, S., bogdanov@google.com, b., Horneffer, M.,
              Steinberg, D., Decraene, B., and S. Litkowski, "Segment
              Routing Policy for Traffic Engineering", draft-filsfils-
              spring-segment-routing-policy-01 (work in progress), July
              2017.

   [I-D.ietf-6man-segment-routing-header]
              Previdi, S., Filsfils, C., Raza, K., Leddy, J., Field, B.,
              daniel.voyer@bell.ca, d., daniel.bernier@bell.ca, d.,
              Matsushima, S., Leung, I., Linkova, J., Aries, E., Kosugi,
              T., Vyncke, E., Lebrun, D., Steinberg, D., and R. Raszuk,
              "IPv6 Segment Routing Header (SRH)", draft-ietf-6man-
              segment-routing-header-07 (work in progress), July 2017.

   [I-D.ietf-idr-segment-routing-te-policy]
              Previdi, S., Filsfils, C., Mattes, P., Rosen, E., and S.
              Lin, "Advertising Segment Routing Policies in BGP", draft-
              ietf-idr-segment-routing-te-policy-00 (work in progress),
              July 2017.

   [I-D.ietf-spring-segment-routing]
              Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
              and R. Shakir, "Segment Routing Architecture", draft-ietf-
              spring-segment-routing-12 (work in progress), June 2017.

   [I-D.ietf-spring-segment-routing-mpls]
              Filsfils, C., Previdi, S., Bashandy, A., Decraene, B.,
              Litkowski, S., and R. Shakir, "Segment Routing with MPLS
              data plane", draft-ietf-spring-segment-routing-mpls-10
              (work in progress), June 2017.




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   [I-D.negi-pce-segment-routing-ipv6]
              Negi, M., Kaladharan, P., Dhody, D., and S. Sivabalan,
              "PCEP Extensions for Segment Routing leveraging the IPv6
              data plane", draft-negi-pce-segment-routing-ipv6-00 (work
              in progress), October 2017.

   [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>.

   [RFC4456]  Bates, T., Chen, E., and R. Chandra, "BGP Route
              Reflection: An Alternative to Full Mesh Internal BGP
              (IBGP)", RFC 4456, DOI 10.17487/RFC4456, April 2006,
              <https://www.rfc-editor.org/info/rfc4456>.

   [RFC4657]  Ash, J., Ed. and J. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol Generic
              Requirements", RFC 4657, DOI 10.17487/RFC4657, September
              2006, <https://www.rfc-editor.org/info/rfc4657>.

   [RFC4674]  Le Roux, J., Ed., "Requirements for Path Computation
              Element (PCE) Discovery", RFC 4674, DOI 10.17487/RFC4674,
              October 2006, <https://www.rfc-editor.org/info/rfc4674>.

   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March 2009,
              <https://www.rfc-editor.org/info/rfc5440>.

   [RFC7752]  Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
              S. Ray, "North-Bound Distribution of Link-State and
              Traffic Engineering (TE) Information Using BGP", RFC 7752,
              DOI 10.17487/RFC7752, March 2016,
              <https://www.rfc-editor.org/info/rfc7752>.

10.2.  Normative References'

   [I-D.filsfils-spring-srv6-network-programming]
              Filsfils, C., Leddy, J., daniel.voyer@bell.ca, d.,
              daniel.bernier@bell.ca, d., Steinberg, D., Raszuk, R.,
              Matsushima, S., Lebrun, D., Decraene, B., Peirens, B.,
              Salsano, S., Naik, G., Elmalky, H., Jonnalagadda, P.,
              Sharif, M., Ayyangar, A., Mynam, S., Henderickx, W.,
              Bashandy, A., Raza, K., Dukes, D., Clad, F., and P.
              Camarillo, "SRv6 Network Programming", draft-filsfils-
              spring-srv6-network-programming-01 (work in progress),
              June 2017.



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Authors' Addresses

   Darren Dukes (editor)
   Cisco Systems
   Canada

   Email: ddukes@cisco.com


   Clarence Filsfils
   Cisco Systems
   Belgium

   Email: cfilsfil@cisco.com


   Gaurav Dawra
   Cisco Systems
   USA

   Email: gdawra@cisco.com


   Pablo Camarillo Garvia
   Cisco Systems
   Spain

   Email: pcamaril@cisco.com


   Francois Clad
   Cisco Systems
   France


   Stefano Salsano
   Univ. of Rome Tor Vergata
   Italy

   Email: stefano.salsano@uniroma2.it











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