Description of Inter-AS Networks in the RIPE Routing Registry

Daniel,

Sorry for the delay in the response.  This is a very useful adendum.

Only one comment...

> Only one AS announces an inter-AS network  externally.   The
> other  ASes  connected to the inter-AS network will probably
> carry this network in their internal routing for  redundancy
> but will not announce it to other ASes.
> 
> In exceptional cases more than one AS may need to  originate
> external  routing  information  about  the inter-AS network,
> This kind of routing setup cannot be  described  within  the
> framework  of  ripe-81  and is generally discouraged.  Tools
> using a ripe-81 type registry  could  take  heuristic  hints
> from  the ias-int attributes when they encounter such situa-
> tions.

Does this mean that if ANS or Merit announces the FixW FDDI, Barrnet
and NASA can't add a pair of routers only peering with each other on
the ring?  Alternet and PSI at College Park are are another example,
but I'm not sure who would "own" that network.  (no side discussions
on this please - redirect to alt.bizarre.politics.gix or /dev/null :).

I think that things like this have been done (and are being done) due
to a rather low limit on the number of peers some routers can support
(not the ENSS of course :).  You may want to allow each AS to announce
it's own routers for the DMZ/FIX/NAP/GIX.

BTW - We use the term "shared network", but out of context it makes
little sense so your term "inter-AS network" seems like a good choice.

Curtis