An MPLS-Based Forwarding Plane for Service Function Chaining
RFC 8595
Document | Type |
RFC - Proposed Standard
(June 2019; No errata)
Was draft-ietf-mpls-sfc (mpls WG)
|
|
---|---|---|---|
Authors | Adrian Farrel , Stewart Bryant , John Drake | ||
Last updated | 2019-06-07 | ||
Replaces | draft-farrel-mpls-sfc | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Loa Andersson | ||
Shepherd write-up | Show (last changed 2018-11-29) | ||
IESG | IESG state | RFC 8595 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Deborah Brungard | ||
Send notices to | Loa Andersson <loa@pi.nu> | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) A. Farrel Request for Comments: 8595 Old Dog Consulting Category: Standards Track S. Bryant ISSN: 2070-1721 Futurewei J. Drake Juniper Networks June 2019 An MPLS-Based Forwarding Plane for Service Function Chaining Abstract This document describes how Service Function Chaining (SFC) can be achieved in an MPLS network by means of a logical representation of the Network Service Header (NSH) in an MPLS label stack. That is, the NSH is not used, but the fields of the NSH are mapped to fields in the MPLS label stack. This approach does not deprecate or replace the NSH, but it acknowledges that there may be a need for an interim deployment of SFC functionality in brownfield networks. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8595. Farrel, et al. Standards Track [Page 1] RFC 8595 MPLS SFC June 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 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction ....................................................3 2. Requirements Language ...........................................4 3. Choice of Data-Plane SPI/SI Representation ......................4 4. Use Case Scenarios ..............................................5 4.1. Label Swapping for Logical NSH .............................5 4.2. Hierarchical Encapsulation .................................5 4.3. Fine Control of Service Function Instances .................6 4.4. Micro Chains and Label Stacking ............................6 4.5. SFC and Segment Routing ....................................6 5. Basic Unit of Representation ....................................6 6. MPLS Label Swapping .............................................7 7. MPLS Label Stacking ............................................10 8. Mixed-Mode Forwarding ..........................................12 9. A Note on Service Function Capabilities and SFC Proxies ........13 10. Control-Plane Considerations ..................................14 11. Use of the Entropy Label ......................................14 12. Metadata ......................................................15 12.1. Indicating Metadata in User Data Packets .................16 12.2. In-Band Programming of Metadata ..........................18 12.2.1. Loss of In-Band Metadata ..........................21 13. Worked Examples ...............................................22 14. Implementation Notes ..........................................26 15. Security Considerations .......................................26 16. IANA Considerations ...........................................28 17. References ....................................................29 17.1. Normative References .....................................29 17.2. Informative References ...................................30 Acknowledgements ..................................................31 Contributors ......................................................31 Authors' Addresses ................................................32 Farrel, et al. Standards Track [Page 2] RFC 8595 MPLS SFC June 2019 1. Introduction Service Function Chaining (SFC) is the process of directing packets through a network so that they can be acted on by an ordered set ofShow full document text