On Mar 18, 2008, at 5:10 AM, Gabi Nakibly wrote: > Determining whether the destination address is in the zone of a > source address can be tricky. However, it is fairly easy in the > common case where the source address is link-local and the > destination address is global. If the latter is not on-link, than > it is not in the zone of the link-local source address and this > source address should not be included in the candidate set. If the > above rule will be applied in the scenario of http://tools.ietf.org/ > html/draft-ietf-v6ops-v6onbydefault-03, the candidate set of the v6 > address will be empty and therefore it will be avoided by > destination address selection rule 1.
Speaking for myself, there is a simpler rule in that special case that imght be instructive in the ULA case. There is no sense in using a link-local address as a source address unless one is sending to someone on the same LAN. Hence, there is no sense in suing a link-local address as the source if one cannot also use one in the destination. Similarly, there is no sense using a ULA source address unless the destination is in the same ULA. If the destination is a global address it might or might not be able to reply, but the sender can't tell. Hence, in sender address choice: - use a link-local source address if and only if the destination is a link-local address - use a ULA source address if and only if the destination is a ULA in the same prefix - otherwise, use a global address -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
