The IESG has approved the following document: - 'Crankback Signaling Extensions for MPLS and GMPLS RSVP-TE ' <draft-ietf-ccamp-crankback-06.txt> as a Proposed Standard This document is the product of the Common Control and Measurement Plane Working Group. The IESG contact persons are Ross Callon and Bill Fenner. A URL of this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-ietf-ccamp-crankback-06.txt Technical Summary In a distributed, constraint-based routing environment, the information used to compute a path may be out of date. This means that Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS) Traffic Engineered (TE) Label Switched Path (LSP) setup requests may be blocked by links or nodes without sufficient resources. Crankback is a scheme whereby setup failure information is returned from the point of failure to allow new setup attempts to be made avoiding the blocked resources. Crankback can also be applied to LSP recovery to indicate the location of the failed link or node. This document specifies crankback signaling extensions for use in MPLS signaling using RSVP-TE as defined in "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC3209, and GMPLS signaling as defined in "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description", RFC3473. These extensions mean that the LSP setup request can be retried on an alternate path that detours around blocked links or nodes. Working Group Summary No dissent. There was some comment that the document contains too many sub-TLVs for conveying crankback information , but for each individual TLV the consensus was to retain it (see PROTO writeup in comments in ID tracker). Protocol Quality Ross Callon reviewed this for the IESG. The spec has been updated in response to comments from the AD (Ross) as well as Security Directorate comments. The document was also liaisoned and reviewed by ITU-T's SG15. Note to RFC Editor There are a few typos, particularly in documents referenced, that need to be corrected. The set of corrections (provided by Adrian Farrel): ==== Section 2.1 s/[RC3473]/[RFC3473]/ === Section 4.5, point 4) s/[RFC4373]/[RFC3473]/ === Section 13 DELETE [G8080] ITU-T Recommendation G.808/Y.1304, Architecture for the Automatically Switched Optical Network (ASON), November 2001. For information on the availability of this document, please see http://www.itu.int. === Section 13 ADD [RFC4201] Kompella, K., Rekhter, Y., and Berger, L. "Link Bundling in MPLS Traffic Engineering (TE)", RFC 4201, October 2005. === _______________________________________________ IETF-Announce@ietf.org https://www1.ietf.org/mailman/listinfo/ietf-announce
