Re: BGP-4+

[Yakov Rekhter <[e-mail]>]

Dennis,
 
> > This is certainly one possibility. Another possibility is to allow
> > MP_REACH_NLRI and MP_UNREACH_NLRI to carry NLRI for multiple address
> > families (this would require minor changes to the proposed encoding).
> 
> This would work too.  Now that I've though about it I think I might have
> a slight preference for doing it your way.  The tradeoff seems to be that
> you have to spend a few more bytes of encoding to do it your way, but
> you get to keep all attributes-that-are-really-routes together in one spot.
> I think the latter is probably a feature.

Ok. We'll modify the document to allow for multiple address families.

> The only other issue I have relates to protocol-specific usage.  I think
> there probably needs to be a paragraph or so on IPv6-specific gorp written
> down somewhere to ensure working, interoperable implementations.  The one
> example I can think of off-hand is that of IPv6 next hop addresses.  Most
> routing protocols for IPv6 specify the exclusive use of link-local addresses
> for next hops, as the interface addresses least likely to change over the
> life of a routing protocol session, but this is probably not right for BGP
> since link-local addresses are not likely to be well-received when
> readvertised via IBGP.

Correct.
  
> Is it intended that protocol-specific (or, at least, IPv6-specific) issues
> are to be documented elsewhere (or anywhere)?  A multiprotocol specification
> by itself seems insufficient.

I would suggest to stick IPv6-specific text into the multiprotocol spec.
But I can be easily convinced otherwise (and have a separate IPv6-specific
doc).

Yakov.