Network Working Group X. Xu
Internet-Draft Huawei
Intended status: Standards Track R. Raszuk
Expires: September 4, 2015 Mirantis Inc.
U. Chunduri
Ericsson
L. Contreras
Telefonica I+D
March 3, 2015

Advertising Encapsulation Capability Using IS-IS
draft-xu-isis-encapsulation-cap-04

Abstract

In a particular network environment where MPLS-SPRING-enabled routers are partially deployed, it needs to transport MPLS traffic through an IP-based tunnel between two MPLS-SPRING-enabled routers so as to traverse non-MPLS routers. The ingress of the IP-based tunnel must know which encapsulation type is supported by the egress of that IP-based tunnel.This document describes how to advertise the encapsulation capability of MPLS-SPRING-enabled routers using IS-IS. Note that this encapsulation capability advertisement may be applicable to other use cases as well.

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 September 4, 2015.

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Table of Contents

1. Introduction

[I-D.xu-spring-islands-connection-over-ip] describes a particular network environment where MPLS-SPRING-enabled routers are partially deployed and therefore it needs to transport MPLS traffic through an IP-based tunnel between two MPLS-SPRING-enabled routers so as to traverse non-MPLS routers. The ingress of the IP-based tunnel (i.e., tunnel encapsulator) must know which encapsulation type is supported by the egress of the IP-based tunnel (i.e., tunnel decapsulator).This document describes how to advertise the encapsulation capability of MPLS-SPRING-enabled routers using IS-IS. Note that this encapsulation capability advertisement may be applicable to other use cases as well.

1.1. Requirements Language

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 RFC 2119 [RFC2119].

2. Terminology

This memo makes use of the terms defined in [RFC4971] and [I-D.xu-spring-islands-connection-over-ip].

3. Advertising Encapsulation Capability

MPLS-SPRING-enabled routers need to advertise the encapsulation type(s) they support by using a new sub-TLV of the IS-IS Router CAPABILITY TLV [RFC4971], referred to as Encapsulation Capability sub-TLV. The Encapsulation Capability sub-TLV SHOULD NOT appear more than once wihin a given IS-IS Router CAPABILITY TLV. The scope of the advertisement depends on the application but it is recommended that it SHOULD be domain-wide. The Type code of the Encapsulation Capability sub-TLV is TBD, the Length value is variable, and the Value field contains one or more Encapsulation Type sub-TLVs with each indicating a particular encapsulation format that the advertising router supports.

This document defines the following types of Encapsulation Type sub-TLV:

  1. MPLS-in-IP tunnel [RFC4023] : Type code=TBD1; Length=0
  2. MPLS-in-GRE tunnel [RFC4023]: Type code=TBD2; Length=0
  3. MPLS-in-L2TPv3 tunnel [RFC4817]: Type code=TBD3; Length=0
  4. MPLS-in-UDP tunnel [I-D.ietf-mpls-in-udp]: Type code=TBD4; Length=0
  5. MPLS-in-IP tunnel with IPsec Transport Mode [RFC5566]: Type code=TBD5; Length=0

4. Acknowledgements

The authors would like to thank Carlos Pignataro and Karsten Thomann for their valuable comments on this draft.

5. IANA Considerations

This memo includes a request to IANA for allocating the type codes for Encapsulation Capability sub-TLV and Encapsulation Type sub-TLVs.

6. Security Considerations

This document does not introduce any new security risk.

7. References

7.1. Normative References

[I-D.xu-spring-islands-connection-over-ip] Xu, X., Raszuk, R., Chunduri, U. and L. Contreras, "Connecting MPLS-SPRING Islands over IP Networks", Internet-Draft draft-xu-spring-islands-connection-over-ip-04, March 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4971] Vasseur, JP., Shen, N. and R. Aggarwal, "Intermediate System to Intermediate System (IS-IS) Extensions for Advertising Router Information", RFC 4971, July 2007.

7.2. Informative References

[I-D.ietf-mpls-in-udp] Xu, X., Sheth, N., Yong, L., Callon, R. and D. Black, "Encapsulating MPLS in UDP", Internet-Draft draft-ietf-mpls-in-udp-11, January 2015.
[RFC4023] Worster, T., Rekhter, Y. and E. Rosen, "Encapsulating MPLS in IP or Generic Routing Encapsulation (GRE)", RFC 4023, March 2005.
[RFC4817] Townsley, M., Pignataro, C., Wainner, S., Seely, T. and J. Young, "Encapsulation of MPLS over Layer 2 Tunneling Protocol Version 3", RFC 4817, March 2007.
[RFC5566] Berger, L., White, R. and E. Rosen, "BGP IPsec Tunnel Encapsulation Attribute", RFC 5566, June 2009.

Authors' Addresses

Xiaohu Xu Huawei EMail: xuxiaohu@huawei.com
Robert Raszuk Mirantis Inc. EMail: robert@raszuk.net
Uma Chunduri Ericsson EMail: uma.chunduri@ericsson.com
Luis M. Contreras Telefonica I+D Ronda de la Comunicacion, s/n Sur-3 building, 3rd floor Madrid,, 28050 Spain EMail: luismiguel.contrerasmurillo@telefonica.com URI: http://people.tid.es/LuisM.Contreras/