Anton Smith <anton@huge.geek.nz> a écrit sur 06/06/2012 09:53:02 AM :
Potentially silly question but, as Bill points out a LAN always occupies a /64.
Does this imply that we would have large L2 segments with a large number of hosts on them? What about the age old discussion about keeping broadcast segments small?
The /64 only removes the limitation on the number of *addresses* on the L2 domain. Limitations still apply for the amount of ARP and ND noise. A maximum number of hosts is reached when that noise floor represents a significant portion of the link bandwidth. If ARP/ND proxying is used, the limiting factor may instead be the CPU on the gateway. The ND noise generated is arguably higher than ARP because of DAD, but I don't remember seeing actual numbers on this (anybody?). I've seen links with up to 15k devices where ARP represented a significant part of the link usage, but most weren't (yet) IPv6. /JF