SDPs are enhanced to use BGP route tunnel to extend inter-AS support for Layer 2 and Layer 3 VPN services. An SDP can be configured to use the MPLS transport method. MPLS SDP support is enhanced to allow a BGP route tunnel to reach the far-end PE. A single method of tunneling is allowed per SDP (for example, LDP, RSVP-TE LSP, or BGP route tunnel). The BGP route tunnel method is excluded if multi-mode transport is enabled for an SDP.
A single method of tunneling is allowed per SDP (for example, LDP, RSVP-TE LSP or BGP route tunnel). BGP route tunnel method is excluded if multimode transport is enabled for an SDP.
For inter-AS far-end PE, the next-hop for the BGP route tunnel must be one of the local ASBRs. The LSP type selected to reach the local ASBR (BGP labeled route next-hop) must be configured under the BGP global context. LDP must be supported to provide a transport LSP to reach the BGP route tunnel next-hop.
Only BGP route labels can be used to transition from an ASBR to the next-hop ASBR. The global BGP route tunnel transport configuration option must be entered to select an LSP to reach the PE node from the ASBR node. On the last BGP segment, both BGP+LDP and LDP routes may be available to reach the far-end PE from the ASBR node. An LDP LSP must be preferred because of higher protocol priority. This leads to just one label, besides other labels in the stack, to identify the VC/VPN at far-end PE nodes.