--- 1/draft-ietf-mpls-sfc-02.txt 2018-10-13 09:13:18.402861621 -0700 +++ 2/draft-ietf-mpls-sfc-03.txt 2018-10-13 09:13:18.462863049 -0700 @@ -1,21 +1,21 @@ MPLS Working Group A. Farrel Internet-Draft Juniper Networks Intended status: Standards Track S. Bryant -Expires: February 6, 2019 Huawei +Expires: April 16, 2019 Huawei J. Drake Juniper Networks - August 5, 2018 + October 13, 2018 An MPLS-Based Forwarding Plane for Service Function Chaining - draft-ietf-mpls-sfc-02 + draft-ietf-mpls-sfc-03 Abstract Service Function Chaining (SFC) is the process of directing packets through a network so that they can be acted on by an ordered set of abstract service functions before being delivered to the intended destination. An architecture for SFC is defined in RFC7665. The Network Service Header (NSH) can be inserted into packets to steer them along a specific path to realize a Service Function Chain. @@ -42,21 +42,21 @@ 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 February 6, 2019. + This Internet-Draft will expire on April 16, 2019. Copyright Notice Copyright (c) 2018 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 @@ -67,25 +67,25 @@ 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 + 4.3. Fine Control of Service Function Instances . . . . . . . 5 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 . . . . . . . . . . . . . . . . . . . . . 8 + 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 . . . . . . . . . . . . . . . . 13 11. Use of the Entropy Label . . . . . . . . . . . . . . . . . . 14 12. Metadata . . . . . . . . . . . . . . . . . . . . . . . . . . 15 12.1. Indicating Metadata in User Data Packets . . . . . . . . 15 12.2. Inband Programming of Metadata . . . . . . . . . . . . . 17 13. Worked Examples . . . . . . . . . . . . . . . . . . . . . . . 20 14. Implementation Notes . . . . . . . . . . . . . . . . . . . . 24 @@ -212,25 +212,24 @@ with an MPLS encapsulation as described in Section 6. The MPLS labels encode the same information as the NSH to form a logical NSH. The labels are modified (swapped per [RFC3031]) at each SFC hop along the chain to indicate the next hop. The processing and forwarding state for a chain (i.e., the actions to take on a received label) are programmed in to the network using a control plane or management plane. 4.2. Hierarchical Encapsulation - [I-D.ietf-sfc-hierarchical] describes an architecture for - hierarchical encapsulation using the NSH. It facilitates - partitioning of SFC domains for administrative reasons, and allows - concatenation of service function chains under the control of a - service classifier. + [RFC8459] describes an architecture for hierarchical encapsulation + using the NSH. It facilitates partitioning of SFC domains for + administrative reasons, and allows concatenation of service function + chains under the control of a service classifier. The same function can be achieved in an MPLS network using an MPLS encoding of the logical NSH, and label stacking as defined in [RFC3031] and described in Section 7. In this model, swapping is used per Section 4.1 to navigate one chain, and when the end of the chain is reached, the final label is popped revealing the label for another chain. Thus, the primary mode is swapping, but stacking is used to enable the ingress classifier to control concatenation of service function chains. @@ -1199,25 +1198,20 @@ DOI 10.17487/RFC8393, May 2018, . 19.2. Informative References [I-D.ietf-bess-nsh-bgp-control-plane] Farrel, A., Drake, J., Rosen, E., Uttaro, J., and L. Jalil, "BGP Control Plane for NSH SFC", draft-ietf-bess- nsh-bgp-control-plane-04 (work in progress), July 2018. - [I-D.ietf-sfc-hierarchical] - Dolson, D., Homma, S., Lopez, D., and M. Boucadair, - "Hierarchical Service Function Chaining (hSFC)", draft- - ietf-sfc-hierarchical-11 (work in progress), June 2018. - [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-14 (work in progress), June 2018. [I-D.xuclad-spring-sr-service-chaining] Clad, F., Xu, X., Filsfils, C., daniel.bernier@bell.ca, d., Li, C., Decraene, B., Ma, S., Yadlapalli, C., Henderickx, W., and S. Salsano, "Segment Routing for @@ -1241,26 +1235,31 @@ [RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function Chaining (SFC) Architecture", RFC 7665, DOI 10.17487/RFC7665, October 2015, . [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, . + [RFC8459] Dolson, D., Homma, S., Lopez, D., and M. Boucadair, + "Hierarchical Service Function Chaining (hSFC)", RFC 8459, + DOI 10.17487/RFC8459, September 2018, + . + Authors' Addresses Adrian Farrel Juniper Networks - Email: afarrel@juniper.net + Email: adrian@olddog.co.uk Stewart Bryant Huawei Email: stewart.bryant@gmail.com John Drake Juniper Networks Email: jdrake@juniper.net