Hi Authors,

I have reviewed this document as part of the Operational directorate's ongoing effort to review all IETF documents being processed by the IESG.  These comments were written with the intent of improving the operational aspects of the IETF drafts. Comments that are not addressed in last call may be included in AD reviews during the IESG review.  Document editors and WG chairs should treat these comments just like any other last call comments.

Document reviewed: draft-ietf-trill-directory-assist-mechanisms-10

Summary:
- This document describes mechanisms for providing directory service to TRILL edge switches, including Pull, Push and Hybrid model.
- I do not find any major issue from the OPS point of view, I think this doc is ready for publication as RFC.

The clarification question:
In 3.5.1, you have "A Pull Directory can be hosted on an end station", and "This capability would be useful in supporting an end station that performs directory assisted encapsulation [DirAsstEncap] or that is a "smart end node" [SmartEN]."

But in Push Model, I did not see the similar option, i.e., the push directory hosted on the end station.
In section 2, you have "one or more Push Directory servers reside at TRILL switches".
Are you indicating that the push directory server can only reside on the trill switch? If so could you please explicitly write down it and give the reason, because it's not obvious to me. 

One editorial:
in 3.5.2 Pull Directory Use by End Stations, s/Use/Used/


Regards,
Tianran