1. SPBM for resilient PB E-NNI
NW 1
PB NW 2
S-Tag = x
S-Tag = y
I-SID = z
Operators 1 & 2 bind each PB S-tag to a common SPBM I-SID
Each operator is responsible for advertising that I-SID once only into the SPBM domain :
but each operator has complete authority as to where that is
So long as a viable path remains available in the SPBM domain, connectivity will automatically be maintained by SPBM.
I-SiDs are provisioned in SPBM :
a signalled interface might be desirable
MVRP / MIRP depending on which side drives it ?