On Wed, 8 Aug 2018 at 23:53, Stan Barber <sob@academ.com> wrote:
but the basic requirements of the network itself (e.g. IPv6 uses multicast instead of broadcast for some network control information distribution).
This is almost never true, it's rare exception rather than common case. The idea was that in IPv4 networks ARP broadcast waste bandwidth and host CPU. To fix this problem, each host (sufficiently small group of IPv6 addresses unlikely to collide) subscribes to its own multicast group. So we don't need to flood the ND traffic to hosts not needing it. But it turned out supporting ~infinitely many multicast states is harder problem than pushing frames in hardware to all ports. So all practical networks run IPv6 ND same as ARP. Another 'we fixed a problem in IPv6', which turned out to be worse than the original problem and was quietly ignored in practical networks. -- ++ytti