Subject: [Bier] [BIER] draft-ietf-bier-mvpn question

From: Xiejingrong <[email-masked]>
Date: Mon, 11 Jun 2018 11:31:25 +0000

HI folks,
Regarding the following text in chap 3 of <draft-ietf-bier-mvpn>, I have a question:
   When an egress PE determines that it needs to receive a (C-S,C-G)
   flow from a particular ingress PE via BIER, it originates a Leaf A-D
   route.  Construction of the Leaf A-D route generally follows the
   procedures specified in [RFC6514], or optionally, the procedures
   specified in [EXPLICIT_TRACKING].

Is the 'it originates a Leaf A-D route' means that, for as few as only one SPMSI A-D(*,*,PTA<type=BIER,flag=LIR+LIRpF>), when an egress PE first determines to receive (C-S1,C-G1), it will only originate Leaf A-D(C-S1,C-G1), but not originate Leaf A-D(C-*,C-*) ?

The chap 3 also allows A "less specific" x-PMSI A-D route being the egress PE's "match for reception" of (C-S,C-G), and thus seems to imply allowing a Leaf A-D(C-*,C-*,PTA<type=BIER>).

Also there is a text in chap 5.1 of <draft-ietf-bess-mvpn-expl-track-09>, which seems opposite to the above meaning:
       Note that if LIR is set in the PTA of the match for reception,
       the egress node may need to originate one or more Leaf A-D routes
       corresponding to the match for tracking, as well as originating a
       Leaf A-D route corresponding to the match for reception.

Thanks
Jingrong