Alvaro, here are some responses. I cut out text I didn't need to comment on.

> [major] This is the only place, including rfc6830bis/rfc6833bis, where
> "proxy-reply mode" is used.  Is this operation specified anywhere,
> maybe using a different name?  This seems to be related to the
> Map-Server being able to offer non-authoritative Map-Replies -- please
> be specific.

In 6833bis, we refer to the P-bit in the Map-Register as "proxy Map-Reply bit". 
And occurs 11 times in 6833bis.


> [major] What happens if one of these assumptions is not met?  If the
> rest of the specification is followed (setting the I and N bits, etc.)
> what are the "failure scenarios" if the conditions are not met?

When the N bit is not set, the message is processed like a regular Map-Request 
(and state is not put in the subscription cache on the map-server). That wasn't 
clear? Alberto?

> 144   4.  Map-Request PubSub Additions
> ...
> 190         xTR-ID bit (I-bit): This bit is set to 1 to indicate that a 128
> 191         bit xTR-ID and a 64 bit Site-ID fields are present at the end of
> 192         the Map-Request message.  For PubSub operation, an xTR MUST be
> 193         configured with an xTR-ID and Site-ID, and it MUST set the I bit
> 194         to 1 and include its xTR-ID and Site-ID in the Map-Request
> 195         messages it generates.
> 
> [nit] s/I bit/I-bit
> 
> 
> [major] "MUST set the I bit to 1 and include its xTR-ID and Site-ID"
> 
> What should the receiver do if the I bit is set but the ID fields are
> not included?
> 
> 
> [major] IANA hasn't assigned this bit yet.  Please include a note with
> a forward reference to ยง10.

We will fix this. If the I bit not set, the Map-Request is not processed as a 
subscribe-request.

> 
> 213   5.  Mapping Request Subscribe Procedures
> 
> 215      The xTR subscribes for changes for a given EID-prefix by sending a
> 216      Map-Request to the Mapping System with the N-bit set on the EID-
> 217      Record.  The xTR builds a Map-Request according to Section 5.3 of
> 218      [I-D.ietf-lisp-rfc6833bis] but also does the following:
> 
> 220      (1)  The xTR MUST set the I-bit to 1 and append its xTR-ID and Site-
> 221           ID to the Map-Request.  The xTR-ID uniquely identifies the xTR.
> 
> 223      (2)  The xTR MUST set the N-bit to 1 for each EID-Record to which the
> 224           xTR wants to subscribe.
> 
> [minor] If I understand correctly, it is ok for a Map-Request to have
> the I-bit set (+ xTR-ID + Site-ID), but include no records with the
> N-bit set.  Is that right?  If so, the mention of the N-bit in the
> intro paragraph makes that a little confusing.

Yes, correct. This is a regular Map-Request that is processed according to 
6833bis procedures.

> ...
> 253      (3)  The Map-Server MUST send the Map-Notify to one of the ITR-RLOCs
> 254           received in the Map-Request (which one is implementation
> 255           specific).
> 
> [major] Does this need to be specified here?  Where are Map-Notify
> messages sent to?  I couldn't find a specific answer, but it seems to
> me that choosing a destination address should be pretty "basic"; i.e.
> something that should have been specified in the base spec.

It is basic but there are many choices, *especially* in the presents of NATs. 
You can send to one of the "Local" RLOCs or to the source IP address of the 
Map-Request. If you want to get the message back to the xTR you need to use the 
source IP address.

> ...
> 279      If an xTR-ID is successfully added to the list of subscribers for an
> 280      EID-Record, the Map-Server MUST extract the nonce and ITR-RLOCs
> 281      present in the Map-Request, and store the association between the
> 282      EID-Record, xTR-ID, ITR-RLOCs and nonce.  Any already present state
> 283      regarding ITR-RLOCs and/or nonce for the same xTR-ID MUST be
> 284      overwritten.
> 
> [major] ...and a Map-Notify MUST be sent, right?   The specification
> of the subscription seems incomplete.

Yes, it must so the xTR knows the subscribe-request made it to the map-server.

> 331      When the xTR receives a Map-Notify with an EID not local to the xTR,
> 332      the xTR knows that the Map-Notify has been received to update an
> 333      entry on its map-cache.  Processing of unsolicited Map-Notify
> 334      messages MUST be explicitly enabled via configuration at the xTR.
> 335      The xTR MUST keep track of the last nonce seen in a Map-Notify
> 336      received as a publication from the Map-Server for the EID-Record.  If
> 337      a Map-Notify received as a publication has a nonce value that is not
> 338      greater than the saved nonce, the xTR drops the Map-Notify message
> 339      and logs the fact a replay attack could have occurred.  To compare
> 340      two nonces, the xTR uses the serial number arithmetic defined in
> 341      [RFC1982] with SERIAL_BITS = 64.  The nonce field space (64 bits) is
> 342      considered large enough to not be depleted during normal operation of
> 343      the protocol (e.g., assuming a fast publication rate of one Map-
> 344      Notify per EID-Record per Map-Server per second, the nonce field
> 345      space will not be depleted in 0.5 trillion years).  The same
> 346      considerations discussed in Section 5.6 of [I-D.ietf-lisp-rfc6833bis]
> 347      regarding storing Map-Register nonces apply here for Map-Notify
> 348      nonces.
> 
> [major] "Processing of unsolicited Map-Notify messages MUST be
> explicitly enabled via configuration at the xTR."
> 
> rfc6833bis added the Map-Notify-Ack, but it doesn't require
> configuration anywhere to process unsolicited Map-Notify messages.
> IOW, this requirement is not in line with rfc6833bis.

Its because in 6833bis all Map-Notify messages are always solicited.

Dino

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