[Pce] Quick review of draft-chen-pce-sr-ingress-protection-00

[Dhruv Dhody <[e-mail]>]

Hi Authors,

I did a quick review of your I-D, but some key questions came up, it
would be nice if they could be clarified before hand.

(1) It needs to be made clear that why does backup egress needs to
know about the details of the primary SR path at the primary ingress?
Since things are driven by PCE/controller and there is no signalling,
the motivation needs to be different than RFC 8424 for RSVP-TE.  IMHO
the only reason for backup ingress to be aware of these details would
be to detect the failure of the primary ingress itself. And the
benefit offered by that isn't clear.

(2) Once the motivations are cleared up, then we should explore the
use of existing techniques like PCEP-Flowspec [1] instead of defining
new sub-TLVs for traffic description.  I see you have a few new things
like virtual network but not clear how they would be used and why are
tightly coupled for this use-case.

I hope you would focus on these aspects during your presentation.
Discussion on the list would be even better.

Thanks,
Dhruv

[1] https://tools.ietf.org/html/draft-ietf-pce-pcep-flowspec-03