The IESG has approved the following document: - 'Common Interval Support in Bidirectional Forwarding Detection' (draft-ietf-bfd-intervals-05.txt) as Informational RFC This document is the product of the Bidirectional Forwarding Detection Working Group. The IESG contact persons are Adrian Farrel and Alia Atlas. A URL of this Internet Draft is: http://datatracker.ietf.org/doc/draft-ietf-bfd-intervals/ Technical Summary Bidirectional Forwarding Detection (BFD) requires that messages are transmitted at regular intervals and provides a way to negotiate the interval used by BFD peers. Some BFD implementations may be restricted to only support several interval values. When such BFD implementations speak to each other, there is a possibility of two sides not being able to find a common value for the interval to run BFD sessions. This document defines a small set of interval values for BFD that we call "Common Intervals", and recommends implementations to support the defined intervals. This solves the problem of finding an interval value that both BFD speakers can support while allowing a simplified implementation as seen for hardware-based BFD. It does not restrict an implementation from supporting more intervals in addition to the Common Intervals. Working Group Summary: Discussion in the working group among known implementers of BFD was relatively quiet but supportive of this document. The only discussion that generated any significant amount of "noise" was the discussion of whether these well known common intervals should have an IANA registry to permit the maintenance of this document without requiring a RFC revision. The consensus of that discussion was that an IANA registry was not desired. Document Quality: Multiple implementations support the full range of documented values in either hardware or software, depending on the implementation. The only value that doesn't have very wide support is the 3.3ms value, but support for this value seems to be becoming more common. Personnel: Document Shepherd: Jeffrey Haas Responsible Area Director: Adrian Farrel
