using "reserved" IPv6 space

Owen DeLong owen at delong.com
Tue Jul 17 06:36:54 UTC 2012


On Jul 16, 2012, at 9:40 PM, Karl Auer wrote:

> On Mon, 2012-07-16 at 23:38 -0400, Matt Addison wrote:
>> Oliver <olipro at 8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa> wrote:
>>> Additionally, as an alternative to RAs, you can simply point default
>>> at the all-routers anycast address.
>> 
>> Wouldn't this result in duplicate packets leaving your network if
>> there were more than 1 router listening to 'all routers' and you (at
>> the MAC layer) multicasted to those listeners?
> 
> I think Oliver meant the subnet router anycast address.
> 
> Anycast gets you to one-of-many. The routers work out which of them is
> currently getting the subnet router anycast traffic. If that router
> drops out for any reason, another of the routers available on the link
> takes over.
> 

Reread the spec... It gets the packet to one or more of the routers and it may well
lead to packet duplication. There may or may not be coordination between the
routers. It isn't in the spec.

Owen





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