Internet DRAFT - draft-mirsky-mpls-oam-mpls-sr-ip

draft-mirsky-mpls-oam-mpls-sr-ip







MPLS Working Group                                             G. Mirsky
Internet-Draft                                                 ZTE Corp.
Intended status: Standards Track                        October 22, 2019
Expires: April 24, 2020


    Operations, Administration, and Maintenance for MPLS-SR over IP
                  draft-mirsky-mpls-oam-mpls-sr-ip-03

Abstract

   Segment routing uses source routing paradigm to traffic engineering
   by specifying segments a packet traverses through the network.  MPLS
   Segment Routing applies that paradigm to an MPLS data plane-based
   networks.  SR-MPLS over IP uses MPLS label stack as a source routing
   instruction set and uses IP encapsulation/tunneling such as MPLS-in-
   UDP as defined in RFC 7510 to realize a source routing mechanism
   across MPLS, IPv4, and IPv6 data planes.  This document describes
   Operations, Administration, and Maintenance operations in SR-MPLS
   over IP environment.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on April 24, 2020.

Copyright Notice

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   document authors.  All rights reserved.

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   to this document.  Code Components extracted from this document must
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   2
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
     2.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   3.  OAM in SR-MPLS over IP  . . . . . . . . . . . . . . . . . . .   3
     3.1.  Fault Management OAM in SR-MPLS over IP . . . . . . . . .   3
     3.2.  Performance Monitoring OAM in SR-MPLS over IP . . . . . .   4
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
     5.1.  Source MEP ID IP Address Type . . . . . . . . . . . . . .   4
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   4
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .   4
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   6

1.  Introduction

   Segment routing [RFC8402] uses source routing paradigm to traffic
   engineering by specifying segments a packet traverses through the
   network.  MPLS Segment Routing (SR-MPLS)
   [I-D.ietf-spring-segment-routing-mpls] applies that paradigm to an
   MPLS data plane-based networks.  SR-MPLS over IP uses MPLS label
   stack as a source routing instruction set and uses IP encapsulation/
   tunneling such as MPLS-in-UDP as defined in [RFC7510] to realize a
   source routing mechanism across MPLS, IPv4, and IPv6 data planes.
   This document describes Operations, Administration, and Maintenance
   (OAM) operations in SR-MPLS over IP environment.

2.  Conventions used in this document

2.1.  Terminology

   MPLS: Multiprotocol Label Switching

   LSP: Label Switched Path

   BFD: Bidirectional Forwarding Detection

   SR Segment Routing

   SR-MPLS Segment Routing in MPLS data plane




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   FEC: Forwarding Equivalence Class

   G-ACh: Generic Associated Channel

   ACH: Associated Channel Header

   GAL: G-ACh Label

   OAM Operations, Administration, and Maintenance

2.2.  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.

3.  OAM in SR-MPLS over IP

   OAM operations support Fault Management and Performance Monitoring
   components of FCAPS framework for network management.  To achieve its
   objectives, Fault Management OAM includes proactive and on-demand
   protocols to provide constant monitoring of the network to detect the
   failure in combination with on-demand tools to efficiently localize
   and characterize the defect.  Performance Monitoring OAM protocols
   support measurement of packet loss and packet delay that enables
   calculation of performance metrics, e.g., packet loss ration, inter-
   packet delay variation, that are useful in monitoring the quality of
   service in the network, detect and quantify the service degradation.

3.1.  Fault Management OAM in SR-MPLS over IP

   Fault management OAM toolset includes protocols to perform on-demand
   failure detection and localization as well as proactively monitor
   path continuity.  An example of the former is echo request/reply,
   e.g., Label Switched Path (LSP) Ping [RFC8029].  An example of the
   latter - Bidirectional Forwarding Detection (BFD) over MPLS LSP
   [RFC5884].  For SR-MPLS environment applicability and use of these
   OAM tools defined in [RFC8287] and [I-D.mirsky-spring-bfd]
   respectively.  Both LSP Ping and BFD can be used either with IP/UDP
   encapsulation or in Generic Associated Channel (G-ACh) [RFC5586].
   The use of IP/UDP encapsulation is well-understood and has been
   defined in [RFC8029]:

      The IP header is set as follows: the source IP address is a
      routable address of the sender; the destination IP address is a
      (randomly chosen) IPv4 address from the range 127/8 or an IPv6



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      address from the range 0:0:0:0:0:FFFF:7F00:0/104.  The IP TTL is
      set to 1.  The source UDP port is chosen by the sender.

   Using the sender's routable address enables the receiver to send an
   echo reply or BFD control packets over the IP network.  In some
   environments, the overhead of extra IP/UDP encapsulations may be
   considered as overburden and make to use more compact G-ACh
   encapsulation instead.  In such a case, the OAM control packet MUST
   be immediately followed by the IP Address TLV
   [I-D.mirsky-mpls-p2mp-bfd] with its Value field containing one of the
   routable IP addresses of the sender.

3.2.  Performance Monitoring OAM in SR-MPLS over IP

   Performance monitoring in SR-MPLS over IP may be performed using
   mechanisms defined in [RFC6374].  Unlike FM OAM protocols for MPLS,
   [RFC6374] does not define the use of IP encapsulation.  Instead, the
   addressing object of the type Return Address MUST be used in two-way
   measurements or queries.

4.  Security Considerations

   This document does not introduce new security aspects but inherits
   all security considerations from [RFC8287], [RFC8029], [RFC5884],
   [I-D.mirsky-spring-bfd].

5.  IANA Considerations

5.1.  Source MEP ID IP Address Type

   TBD.

6.  Acknowledgements

   TBD

7.  Normative References

   [I-D.ietf-spring-segment-routing-mpls]
              Bashandy, A., Filsfils, C., Previdi, S., Decraene, B.,
              Litkowski, S., and R. Shakir, "Segment Routing with MPLS
              data plane", draft-ietf-spring-segment-routing-mpls-22
              (work in progress), May 2019.

   [I-D.mirsky-mpls-p2mp-bfd]
              Mirsky, G., "BFD for Multipoint Networks over Point-to-
              Multi-Point MPLS LSP", draft-mirsky-mpls-p2mp-bfd-07 (work
              in progress), June 2019.



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   [I-D.mirsky-spring-bfd]
              Mirsky, G., Tantsura, J., Varlashkin, I., and M. Chen,
              "Bidirectional Forwarding Detection (BFD) in Segment
              Routing Networks Using MPLS Dataplane", draft-mirsky-
              spring-bfd-08 (work in progress), August 2019.

   [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>.

   [RFC5586]  Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed.,
              "MPLS Generic Associated Channel", RFC 5586,
              DOI 10.17487/RFC5586, June 2009,
              <https://www.rfc-editor.org/info/rfc5586>.

   [RFC5884]  Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
              "Bidirectional Forwarding Detection (BFD) for MPLS Label
              Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884,
              June 2010, <https://www.rfc-editor.org/info/rfc5884>.

   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay
              Measurement for MPLS Networks", RFC 6374,
              DOI 10.17487/RFC6374, September 2011,
              <https://www.rfc-editor.org/info/rfc6374>.

   [RFC7510]  Xu, X., Sheth, N., Yong, L., Callon, R., and D. Black,
              "Encapsulating MPLS in UDP", RFC 7510,
              DOI 10.17487/RFC7510, April 2015,
              <https://www.rfc-editor.org/info/rfc7510>.

   [RFC8029]  Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
              Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
              Switched (MPLS) Data-Plane Failures", RFC 8029,
              DOI 10.17487/RFC8029, March 2017,
              <https://www.rfc-editor.org/info/rfc8029>.

   [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>.

   [RFC8287]  Kumar, N., Ed., Pignataro, C., Ed., Swallow, G., Akiya,
              N., Kini, S., and M. Chen, "Label Switched Path (LSP)
              Ping/Traceroute for Segment Routing (SR) IGP-Prefix and
              IGP-Adjacency Segment Identifiers (SIDs) with MPLS Data
              Planes", RFC 8287, DOI 10.17487/RFC8287, December 2017,
              <https://www.rfc-editor.org/info/rfc8287>.




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   [RFC8402]  Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
              Decraene, B., Litkowski, S., and R. Shakir, "Segment
              Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
              July 2018, <https://www.rfc-editor.org/info/rfc8402>.

Author's Address

   Greg Mirsky
   ZTE Corp.

   Email: gregimirsky@gmail.com








































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