At Thu, 10 Jul 2008 12:09:01 -0400, "Hemant Singh (shemant)" <[EMAIL PROTECTED]> wrote:
> Since you don't want any new rules added by our draft, we changed bullet > 3 related to caching on-link determination. The new bullet text does not > add any normative requirements but clearly says why it is a bad idea to > cache on-link determination. Also, our draft is about on-link > determination - we are not adding anything related to IPv6 address > caching - we have said repeatedly, save it for another day. The new text does not make sense to me. In this scenario, the same problem can occur when a host (that just keeps working, without a reboot) happens to fail to receive the RAs containing 0-lifetime prefixes (such a failure can happen for various reasons: there may be a temporary failure in an intermediate switch; the host may have been just too busy and cannot handle the RAs, etc). So, what's wrong in this scenario is that the router doesn't keep advertising 0-lifetime-prefixes sufficiently long. This scenario itself doesn't explain 'why caching on-link prefix is a bad idea'. This story also explains why I previously said "such caching is a minor implementation detail". In terms of external behavior, a node that caches configured address/on-link prefix and reuses it after a reboot is often indistinguishable from a node that happens to fail receiving some updates from RA for some period. Killing the former (while forgetting the latter) can just miss the more fundamental problem. Aside from this essential point, the new bullet does also not make sense in the context of 'A correctly implemented IPv6 host MUST adhere to the following rules'. If we find any valid 'justification' like this, it should be described outside this listing, somewhere more appropriate in the entire context. --- JINMEI, Tatuya Internet Systems Consortium, Inc. -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
