Blocking IPv6 broadcast


I have a customer connected to my Cisco 3560 switch via Gigabit
Ethernet, recently I noticed that he is broadcasting IPv6 packets

such as LLMNR, DHCPv6 and ICMPv6 it seems that the customer is
connecting a Vista machine that has some IPv6 services enabled

(some IPv6 services are enabled by default on Vista)

How can I block such broadcast from entering my network?

By the way there is no firewall in this setup, just a switch to switch.



If you are not doing any L2 security for IPv6, you probably want to block the IPv6 ethertype packets altogether.

Found a link here that might be useful:


I suggest anyone with L2 possibility between customers to implement something like this to avoid rogue RAs.