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MPLS Inter-AS VPN: IPv4+ Labels in BGP versus MPLS LDP

I'm trying to decide between two ways to advertise the PE loopbacks in an MPLS VPN Inter-AS configuration: LDP, and BGP IPv4+ (RFC 3107). I understand that BGP provides the ability to filter routers, but with the introduction of the feature "MPLS LDP Inbound Label Filtering," LDP can be filtered as well. Does this put LDP on par with BGP; what reasons might make me choose one or the other as my preferred method?

Links to feature descriptions:

MPLS LDP Inbound Label Binding Filtering

MPLS VPN—Inter-AS—IPv4 BGP Label Distribution


Reid Knuttila

Network Engineer

Onvoy, Inc.

Cisco Employee

Re: MPLS Inter-AS VPN: IPv4+ Labels in BGP versus MPLS LDP

My prefer to use BGP (IPv4+label). The reason I don't like to use the LDP option is that you need to redistribute the loopback adresses you learn from the remote AS into your IGP for this solution to work. Remember that LDP won't allocate labels forBGP learnt routes.

Hope tis helps,

Harold Ritter
Sr. Technical Leader
CCIE 4168 (R&S, SP)
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