Subject: [Bier] Zaheduzzaman Sarker's No Objection on draft-ietf-bier-te-arch-10: (with COMMENT)

From: Zaheduzzaman Sarker via Datatracker <[email-masked]>
Date: Thu, 26 Aug 2021 05:15:48 -0700

Zaheduzzaman Sarker has entered the following ballot position for
draft-ietf-bier-te-arch-10: No Objection

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COMMENT:
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Thanks for the efforts on this document. Due to lack of time on my side
(apologies) I quickly read through the document and didn't find any transport
related issue sticking out. I agree with TSVART reviewer (Thanks Tommy Pauly)
that this seems useful to reduce duplicate packets to avoid unnecessary effects
in the higher layers.

I have two clarification questions:

* Section 5.3.6.2: if there is 6 SIs in the example then why does the it loops
through only 5 of them? see the text below -

    On all area edge BFR, bea in
   BIFT:SI=k|k=2...6 is populated with forward_routed(BFRka) and beb in
   BIFT:SI=k with forward_routed(BFRkb).

   For BIER-TE forwarding of a packet to a subset of BFERs across all
   areas, a BFIR would create at most 6 copies, with SI=1...SI=6,

* This might be completely my misunderstanding, however, I understood that
BIER-TE supports multiple domains and subdomains, where multiple domains may
not be under same implementer. In that case, would their not be issues for
BIER-TE controllers to show robust behavior if there is no default ECMP
algorithm? Also the implementer is expected to document their ECMP of choice, I
didn't understand in what format and to who the documentation applies. Also
there is no discussions on what happens if there is no such documentation.