[c-nsp] MPLS, L2TPv3 Layer 2/3 VPN Network Options

[Oliver Boehmer (oboehmer)]

> 
> One thing I've been curious about but haven't had the time/gear to
> lab is whether MPLS VPN (vpnv4 BGP/LDP) will play nice with the
> "confederation per pop" style of BGP confederations.  We're currently
> a mix of partially meshed and multiple route reflectors, and it's
> getting to be a bit of a mess to maintain.

If you want to run MPLS-VPN in a BGP confederation setup, you will
essentially build an Inter-AS MPLS-VPN network. 

If you run a common IGP across all confed sub-AS', you don't need to
worry about BGP next-hop, the only thing you need to disable on your
confed-eBGP borders is the automatic RT filter, otherwise it will drop
the vpnv4 updates (unless you configure all the VRFs on this router).

Not sure, but I'd rather clean-up the RR set-up than introduce confeds..
running MPLS in your core enables you to totally separate control and
forwarding plane (i.e. remove BGP from your P devices) which makes RR
placement very easy and straight-forward.

	oli