I am an assigned INT directorate reviewer for draft-ietf-bess-pbb-evpn-isid-cmacflush-08. These comments were written primarily for the benefit of the Internet Area Directors. Document editors and shepherd(s) should treat these comments just like they would treat comments from any other IETF contributors and resolve them along with any other Last Call comments that have been received. For more details on the INT Directorate, see https://datatracker.ietf.org/group/intdir/about/ <https://datatracker.ietf.org/group/intdir/about/>.


Based on my review, if I was on the IESG I would ballot this document as NO OBJECTION.

The following are other issues I found with this document that SHOULD be corrected before publication:

Please indicate how the CE can know if the PW failure is not due to the PE failure, in which case extending the Customer MAC flush solution in RFC7623 seems more efficient as all I-SIDs with link / PW starting there are affected. And how the double flush in avoided in the case of a non-null ESI with this spec on as well.

I found this 
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When I-SID-based C-MAC-flush is disabled, the PE will follow the [RFC7623] procedures for C-MAC-flush.
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but it does not answer either of the above. e.g., does the reciprocal of the above apply too? or can they be both on? 

I'd have thought that upon loss of connectivity with PE3, CE3 enables the PW to PE4 and tells PE4 to send the update. Now it seems that the main player of this spec is actually PE4 and that it's death is reported some other way. If that's correct, saying it earlier would have saved me a headache ;)

The following are minor issues (typos, misspelling, minor text improvements) with the document:

First use (in intro) of "Ethernet Segments" add "(ES)" since ES and ESI are used later. On second use (with multi home) please indicate whether that is equivalent to non-null ESI and virtual ES since they seem to be used interchangeably later.


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Since there are no multi-homed ES defined, the PEs keep their Attachment Circuits active as long as the physical connectivity is established and the CEs are responsible for managing the redundancy, avoiding loops and providing per-I-SID load balancing to the PBB-EVPN network.
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This makes sense but a reference to a spec that explains that in details (: to the dumb reader :) would be appreciated. Is this all in RFC7623?


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For instance, CE2 will block its link to CE1 and CE3 will block its forwarding path to PE4.
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I understand that's the normal before-failure condition, like having the ring open between CE1 and CE2.
Suggestion:

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For instance, in normal conditions, CE2 will block its link to CE1 and CE3 will block its forwarding path to PE4.
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On first use of the BMAC/X format please clarify that it means BMAC/ISID. This appears later but without clarification.