IPv6 routing /48s

Mark Andrews Mark_Andrews at isc.org
Tue Nov 25 19:57:21 CST 2008


In message <20081126012326.GR78345 at burnout.tpb.net>, Niels Bakker writes:
> * Mark_Andrews at isc.org (Mark Andrews) [Wed 26 Nov 2008, 01:55 CET]:
> > In message <20081126002425.GO78345 at burnout.tpb.net>, Niels Bakker writes:
> >> * alh-ietf at tndh.net (Tony Hain) [Wed 26 Nov 2008, 01:03 CET]:
> >>> In any case, content providers can avoid the confusion if they simply put
>  up
> >>> a local 6to4 router alongside their 2001:: prefix, and populate DNS with
> >>> both. Longest match will cause 2001:: connected systems to chose that dst
> ,
> >>> while 6to4 connected systems will chose 2002:: as the dst. There is no ne
> ed
> >> Huh?  Longest match done by web browsers and other applications?  Since 
> >> when?
> > FreeBSD 6 has is as part of the standard getaddrinfo() implementation.
> 
> I don't see that do any differentiation between 2001::/32, 2002::/16 
> and 2000::/8; only between IPv6-mapped IPv4 addresses and various 
> interface/link/site-local addresses.  And even that function has a big
>   * XXX: we should standardize the functions and link them as standard
>   * library.
> warning stuck on top of it

	2002::/16 vs non 2002::/16 should be in the policy table.
	This is the default prefer ipv6 policy table for FreeBSD
	6.4-PRERELEASE.  There is also a alternate prefer ipv4 policy
	table that will be set if IPv6 is disabled.

Prefix                          Prec Label      Use
::1/128                           50     0        0
::/0                              40     1     4997
2002::/16                         30     2        0
::/96                             20     3        0
::ffff:0.0.0.0/96                 10     4        0

	Mark
	
> 	-- Niels.
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org




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