Failover IPv6 with multiple PA prefixes (Was: IPv6 fc00::/7 - Unique local addresses)

Mon Nov 1 16:07:12 UTC 2010

On Mon, 1 Nov 2010 10:24:31 +0000 (GMT)
Tim Franklin <tim at pelican.org> wrote:

> > Surely your not saying "we ought to make getting PI easy, easy enough
> > that the other options just don't make sense" so that all residential
> > users get PI so that if their ISP disappears their network doesn't
> > break?
> 
> I've seen this last point come up a few times, and I really don't get it.
> 
> If you're multihomed with multiple PA GUAs, yes, you'd want each RA to track its corresponding WAN availability so your devices are using a prefix that has connectivity.
> 
> If you're a single-homed leaf network, why on earth wouldn't you want to generate RAs for your statically-assigned prefix all the time, regardless of the state of your WAN connection?
> 

This isn't to do with anything low level like RAs. This is about
people proposing every IPv6 end-site gets PI i.e. a default free zone
with multiple billions of routes instead of using ULAs for internal,
stable addressing. It's as though they're not aware that the majority
of end-sites on the Internet are residential ones, and that PI can
scale to that number of end-sites. I can't see any other way to
interpret "we ought to make getting PI easy, easy enough that the other
options just don't make sense".

Regards,
Mark.