MPLS-based Service Function Path(SFP) Consistency Verification
draft-lm-mpls-sfc-path-verification-00

Document Type Active Internet-Draft (individual)
Last updated 2020-07-12
Stream (None)
Intended RFC status (None)
Formats plain text xml pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
MPLS Working Group                                                Y. Liu
Internet-Draft                                                 G. Mirsky
Intended status: Standards Track                         ZTE Corporation
Expires: January 13, 2021                                  July 12, 2020

     MPLS-based Service Function Path(SFP) Consistency Verification
                 draft-lm-mpls-sfc-path-verification-00

Abstract

   This document proposes a method to verify the correlation between
   Service Function Chaining control and/or management plane view of the
   specified Service Function Path and the state of its data.  It works
   for both SR service programming and MPLS-based NSH SFC.

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 January 13, 2021.

Copyright Notice

   Copyright (c) 2020 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
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Liu & Mirsky            Expires January 13, 2021                [Page 1]
Internet-Draft              LSP Ping for SFC                   July 2020

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   2
     2.1.  Acronyms  . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.  MPLS-based SFP Consistency Verification . . . . . . . . . . .   3
     3.1.  MPLS-based SFP Consistency Verification . . . . . . . . .   4
     3.2.  SFC Info Sub-TLV  . . . . . . . . . . . . . . . . . . . .   4
     3.3.  SFC Basic Unit FEC Sub-TLV  . . . . . . . . . . . . . . .   6
     3.4.  Theory of Operation . . . . . . . . . . . . . . . . . . .   6
       3.4.1.  MPLS-based service programming  . . . . . . . . . . .   7
       3.4.2.  RFC 8595 path consistency . . . . . . . . . . . . . .   7
     3.5.  Discussion  . . . . . . . . . . . . . . . . . . . . . . .   8
   4.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     4.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     4.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   9

1.  Introduction

   Service Function Chain (SFC) defines an ordered set of service
   functions (SFs) to be applied to packets and/or frames, and/or flows
   selected as a result of classification.

   SFC can be achieved through a variety of encapsulation methods, such
   as NSH [RFC8300], SR service programming
   [I-D.ietf-spring-sr-service-programming] and MPLS-based NSH SFC
   [RFC8595].

   This document describes extensions to MPLS LSP ping [RFC8029]
   mechanisms to support verification between the control/management
   plane and the data plane state for both SR-MPLS service programming
   and MPLS-based NSH SFC.

2.  Conventions used in this document

2.1.  Acronyms

   SFC: Service Function Chain

   SFF: Service Function Forwarder

   SF: Service Function

   SFP: Service Function Path

   RSP: Rendered Service Path

Liu & Mirsky            Expires January 13, 2021                [Page 2]
Internet-Draft              LSP Ping for SFC                   July 2020

3.  MPLS-based SFP Consistency Verification

   MPLS echo request and reply messages [RFC8029] can be extended to
   support the verification of the consistency of an MPLS-based Service
   Function Path (SFP).

   SR-MPLS/MPLS can be used to realize an SFP.  Two methods have been
   defined:

   o  [I-D.ietf-spring-sr-service-programming] describes how to achieve
      service function chaining in SR-enabled MPLS and IPv6 networks.
      In an SR-MPLS network, each SF is associated with an MPLS label.
      As a result, an SFP can be encoded as a stack of MPLS labels and
      pushed on top of the packet.

Show full document text