[afripv6-discuss] Introduction to 6to4

Graham Beneke graham_bulk at apolix.co.za
Wed Jun 6 21:29:29 SAST 2007


Hi Jordi

Thanks for this very good overview.

I have been doing a number of test deployments of 6to4 and it seems to
be fairly easy to get running.

I have been trying to find out about setting up 6to4 relay routers as
all the ones that are currently announced globally are at least an ocean
away from us. Can you provide information about how to go about this?


JORDI PALET MARTINEZ wrote:
> Introduction to 6to4
> =====================
> 
> 6to4 is a transition mechanism that allows IPv6 to be encapsulated in IPv4
> packets (using protocol 41), in order to traverse IPv4-only networks and for
> example, allow transit of IPv6 thru ISPs that only offer IPv4 service.
> 
> In principle, it requires a public IPv4 address.
> 
> According to RFC3056 there are two ways a router could support the 6to4
> transition mechanism.
> 
> The first is called 6to4 Router and the second 6to4 Relay Router.
> 
> 1) 6to4 Router: An IPv6 router supporting a 6to4 pseudo-interface. It is
> normally the border router between an IPv6 site and a wide-area IPv4
> network.
> 
> For example, think in an isolated IPv6 cloud. This cloud could use 6to4
> addresses and get connected to other IPv6 nodes through the 6to4 router.
> 
> 2) 6to4 Relay Router: A 6to4 router configured to support transit routing
> between 6to4 addresses and native IPv6 addresses.
> 
> The main difference with the 6to4 Router is that the Relay router is
> connected to the native IPv6 world. Or what is the same, they announce the
> 2002::/16 prefix to their routing peers.
> 
> Note that an isolated host could be configured as 6to4 router just to
> obtain IPv6 connectivity (this is called a 6to4 router/host). This
> configuration is automatic in many operating systems, and in practice, in
> means that when a host has IPv6 enabled and a public IPv4 address, if it
> supports 6to4, it will gain automatic access to IPv6 even if the ISP doesn't
> provide the service.
> 
> The 6to4 addresses use the prefix 2002::/16
> 
> For the automatic configuration of the 6to4 hosts in order to reach a 6to4
> relay, the 6to4 relays need to use an anycast address, which is 192.88.99.1.
> More info on this in RFC3068.
> 
> 
> More information and pictures are available at:
> http://www.ipv6tf.org/index.php?page=using/connectivity/6to4


-- 

  Graham Beneke
  Apolix Internet Services

E-Mail/MSN/Jabber: graham at apolix.co.za <mailto:graham at apolix.co.za>
Cell: 082-432-1873 <callto://+27824321873>
Skype: grbeneke <callto://grbeneke>
WEB: www.apolix.co.za <http://www.apolix.co.za/>



More information about the afripv6-discuss mailing list