Subject: [mpls] Segment routing to an external adjacency in MPLS (draft-filsfils-spring-segment-routing-mpls-00 )

From: Jafar Akhbarizadeh <[email-masked]>
Date: Fri, 28 Feb 2014 02:17:39 +0000

Hello Ahmad and Stefano,

Section x in SR architecture draft (draft-filsfils-rtgwg-segment-routing-01) talks about allocating ADJ-SID to an external link across two AS's.
A use case is described for this case in section 4.1.3 of draft-filsfils-rtgwg-segment-routing-use-cases.
However, it is not clear how this 'external peering' should be implemented in MPLS. Should the SR label representing  the remote adjacency be swapped? What about the labels underneath it?
What assumptions must be made regarding MPLS support across the two AS's?
I believe a section needs to be added to segment-routing-mpls draft to address external peering.

Thanks,
Jafar Akhbari

Infrastructure and Networking / XGS
Broadcom Corporation