nanog mailing list archives

Re: Thousands of hosts on a gigabit LAN, maybe not


From: Bruce Simpson <bms () fastmail net>
Date: Sun, 10 May 2015 05:01:42 +0100

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:
http://blog.bimajority.org/2014/09/05/the-network-nightmare-that-ate-my-week/


Current thread: