Thousands of hosts on a gigabit LAN, maybe not

Bruce Simpson bms at
Sun May 10 04:01:42 UTC 2015

On 09/05/2015 23:33, Karl Auer wrote:
> IPv4 ARP, for example, hits every on-subnet neighbour; the IPv6
> equivalent uses multicast to hit only those neighbours that happen to
> share the same 24 low-end L3 address bits as the desired target - a
> statistically much smaller subset of on-link neighbours, and in "normal"
> subnets typically only one host. Only chatter that really should go to
> all hosts does so - such as router advertisements.

Except when the IPv6 solicited-node multicast groups cause $VENDOR 
switch meltdown:

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