Paul de Weerd <[EMAIL PROTECTED]> wrote: > | Link-local v6 addresses also work fine because they don't involve > | neighbor discovery. > > Uhm, why ? > > 23:37:41.664994 00:0c:29:e5:f9:24 33:33:ff:ff:4d:0d 86dd 86: > fe80::20c:29ff:fee5:f924 > ff02::1:ffff:4d0d: icmp6: neighbor sol: who > has fe80::20c:29ff:feff:4d0d(src lladdr: 00:0c:29:e5:f9:24) (len 32, > hlim 255)
I stand corrected. > How would you determine the linklayer address of your neighbour without > neighbor discovery ? Well, you could, since the link-local address is reversibly constructed from the link-layer address. On further reflection, I realize that not all the world is ethernet and this relation might not be true for other types of interfaces. Vexingly, I seem to remember that at one time I actually verified this behavior. I must have made a mistake then. My interest was the influence of neighbor discovery on NTP. Some fresh tcpdumping here shows that the typical packet exchange goes like this: 0 sec NTP request ---> <----- NTP reply +5 sec neighbor sol --> <-- neighbor adv <-- neighbor sol neighbor adv --> That seems counterintuitive, but it is nice for NTP. -- Christian "naddy" Weisgerber [EMAIL PROTECTED]