On Tue, 22 Feb 2011, Brian E Carpenter wrote:
Well, I object to drawing anyone's attention to the Appendix of 2460, which is explicitly not part of the standard. And I think that the main text in 2460 is underspecified, whereas RFC 3697 has proved to be plain confusing. And we don't yet have clear consenus on 3697bis. Does all this belong in a requirements list?
Which part of 3697 that is relevant to this document is plain confusing? Those that pertain to this spec are IMHO in Section 3 which seems clear enough to me (copied below).
3. Flow Labeling Requirements To enable Flow Label based classification, source nodes SHOULD assign each unrelated transport connection and application data stream to a new flow. The source node MAY also take part in flow state establishment methods that result in assigning certain packets to specific flows. A source node which does not assign traffic to flows MUST set the Flow Label to zero. To enable applications and transport protocols to define what packets constitute a flow, the source node MUST provide means for the applications and transport protocols to specify the Flow Label values to be used with their flows. The use of the means to specify Flow Label values is subject to appropriate privileges (see section 5.1). The source node SHOULD be able to select unused Flow Label values for flows not requesting a specific value to be used. A source node MUST ensure that it does not unintentionally reuse Flow Label values it is currently using or has recently used when creating new flows. Flow Label values previously used with a specific pair of source and destination addresses MUST NOT be assigned to new flows with the same address pair within 120 seconds of the termination of the previous flow. The source node SHOULD provide the means for the applications and transport protocols to specify quarantine periods longer than the default 120 seconds for individual flows. To avoid accidental Flow Label value reuse, the source node SHOULD select new Flow Label values in a well-defined sequence (e.g., sequential or pseudo-random) and use an initial value that avoids reuse of recently used Flow Label values each time the system restarts. The initial value SHOULD be derived from a previous value stored in non-volatile memory, or in the absence of such history, a randomly generated initial value using techniques that produce good randomness properties [RND] SHOULD be used. -- Pekka Savola "You each name yourselves king, yet the Netcore Oy kingdom bleeds." Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
