> > > A NA with S=0,O=0 for a REACHABLE entry will have no > effect on the > > > entry according to the Appendix C state machine, and > these are the > > > only NAs which the ON will sent to All Nodes which Tentative. > > > Admittedly an NA with S=1,O=0 will reset a REACHABLE > entry to STALE, > > > but why is the correspondent soliciting for a REACHABLE > entry? (Or > > > have I missed something elsewhere?)
Here's a real scenario where you will receive an NA with S=1, O=0 in the REACHABLE state. You try to resolve an anycast address by sending an NS. You receive a first NA and transition to REACHABLE. Then you receive a second NA with S=1, O=0. You want to ignore this second NA. The situation where you receive an NA with S=0, O=0 when not INCOMPLETE is this: Someone is proactively advertising an address (perhaps because of a configuration change) and wants to update any stale neighbor caches out there. So if your link-layer address is different than the one in the NA, move from REACHABLE to STALE to speed-up NUD if the cached link-layer address is now bad. If it's actually still good, you haven't done much damage by moving to STALE. Rich -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
