website in ipv6

Kenny Sallee kenny.sallee at
Tue Jun 28 18:09:04 UTC 2011

> > >
> > I did this by creating a 6to4 tunnel to a relay provided by
> 6in4, not 6to4.  While HE do operate 6to4 relays, the brokered tunnel
> service is 6in4.
A very important distinction I didn't have clear in my head.  To regurgitate
some reading I just completed: both methods use v6 in v4 tunneling using ip
proto 41 in the IPv4 protocol field.  However, 6to4 derives the IPv4 tunnel
destination of an IPv6 packet based on bits 17-48 of the IPv6 packet - which
when converted, equals the 32 bit IPv4 destination.  While 6in4 is
statically configured IPv4 source and destination IP addresses on the Tunnel
(gre) interface.  In Cisco world the config comes down to 'tunnel mode
ipv6ip' vs 'tunnel mode ipv6ip 6to4' and a few other lines of config.

Of course there are a lot more details then that searchable via google.
 Thanks for pointing out my mistake - it helped me learn some more!  Later,

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