In a message written on Fri, Apr 05, 2013 at 09:32:52AM +0200, Adam Vitkovsky wrote:
I thought people where doing it because IGP converged faster than iBGP and in case of an external link failure the ingress PE was informed via IGP that it has to find an alternate next-hop. Though now with the advent of BGP PIC this is not an argument anymore.
You're talking about stuff that's all 7-10 years after the decisions were made that I described in my previous e-mail. Tag switching (now MPLS) had not yet been invented/deployed when the first "next-hop-self" wave occured it was all about scaling both the IGP and BGP. In some MPLS topologies it may speed re-routing to have edge interfaces in the IGP due to the faster convergence of IGP's. YMMV, Batteries not Included, Some Assembly Required. -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/