On 2004-05-31, Pekka Savola wrote: > > Below are my comments on draft-ietf-ipv6-optimistic-dad-00.txt.
Thanks for your feedback Pekka, I've added some thoughts/responses below. All comments welcome! > 1) The draft specifies that instead of using a tentative address as the > source address for RS, another address or the unspecified address should be > used instead. To me, using the unspecified address would seem shortsighted, > so I'd like to disallow its use in this context. (This might cause a > problem, though, because I don't think the nodes typically have an another > address they can use...) You're right ... it's used when a node has no alternative. Using the unspecified address is allowed by RFC2461 6.3.7 (and this is unchanged in -bis-01) so it's a fallback behaviour for OptiDAD. Perhaps I need to be more careful to explain this? > 2) I don't think the memo is clear enough how a Tentative address on > an ON compares to the tentative address on a standard node? I mean, > if the communication can proceed immediately, this would imply that > the address should be flagged as non-tentative, or as > "permanent-optimistic" (which would be seen as non-tentative outside > of Neighbor Discovery). The point is, how are these addresses to be > handled at RFC3484 and other documents which reference tentative vs > non-tentative? That's a really good point, and one I hadn't considered at all :-(. I'll have a think. I guess the obvious solution is to s/Tentative Address/Optimistic Address/ throughout. But this would add an extra state to neighbour discovery, confusing the issue with RFC3484 further. Perhaps I could indicate that Optimistic addresses can be regarded as equivalent to Deprecated, eg: their use should be avoided if there is an alternative. > 3) IMHO, section 3.3 on Address Generation is largely redundant or downright > inappropriate. It describes a few useful things, but also goes on to > specify how to regenerate the addresses if a conflict is found. This is > IMHO very much out of scope for oDAD. At the very least, it should be moved > to an appendix, but I'd vote for removal completely. Okay, I can see your point. Thinking about it, the logical place is perhaps in 2462-bis ... replacing the 5.4.5 behaviour with something a little more ... mobile-oriented. Should I leave it as an appendix in the meantime? > What might be useful is specifying with which kind of addresses oDAD should > be assumed: e.g., those addresses with the universal bit on are a prime > target. Also those addresses which are randomly generated (RFC3041 or SEND) > should be OK. Manual addresses or DHCPv6 in particular should be disallowed. Yeah, I've said "The Optimistic algorithm SHOULD NOT be used on manually configured addresses [...]" in the aforementioned 3.3. Which is kind of how all that address configuration stuff got drawn in to OptiDAD in the first place. > [various comments about boilerplate &c ] noted. I will be certain to fix these for -01. > An address collision with a router may cause neighbours' > IsRouter flags for that address to be cleared, however the RA > sent in response will reset the IsRouter flag. > > ==> s/however/even though/ ? Hmmm. Actually, I'm not happy with that clause at all, let me have a think about it and get back to you all. Thanks again for your feedback ... well, now there's a couple of open issues I'll have to make an Issues List! -----Nick more info: <http://www.ctie.monash.edu.au/ipv6/fastho/> -------------------------------------------------------------------- IETF IPv6 working group mailing list [EMAIL PROTECTED] Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------