Last Call Review of draft-ietf-anima-grasp-09
review-ietf-anima-grasp-09-genart-lc-halpern-2017-02-25-00

Team General Area Review Team (Gen-ART) (genart)
Title Last Call Review of draft-ietf-anima-grasp-09
Request Last Call - requested 2017-02-16
Reviewer Joel Halpern
Review result Ready with Nits
Posted at https://mailarchive.ietf.org/arch/msg/gen-art/d3D_RIyoMNDEULkmnYruV2qJVOY
Last updated 2017-02-25

Review
review-ietf-anima-grasp-09-genart-lc-halpern-2017-02-25

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Document: draft-ietf-anima-grasp-??
Reviewer: Joel Halpern
Review Date: 2017-02-25
IETF LC End Date: 2017-03-02
IESG Telechat date: Not scheduled for a telechat

Summary:

Major issues:

Minor issues:
     Section 2.2 states that routing protocols mainly consider link up/down and that "all nodes need a consistent view of the network topology".  the first seems an over-generalization, since all routing protocols have metrics, and almost all modern routing protocols carry significant additional information about the links and nodes.  The second statement about consistency is true for some protocols, but is not true for external use of BGP nor, as I understand it, for Babel.  So it seems again too strong a characterization.  The following sentence about information not normally used also seems to be at odds with current practice.

    Bullet 1 under SN7 in section 2.2  talks about the potential for circular dependence, and then says that this protocol will not provide any assistance for that.  given that such dependence may be complex.  In particular, given that these dependencies result in separate negotiations, the chain of efforts would continue even if the initial impetus has timed out.  If a single negotiation causes two dependent negotiations, this would seem to have the potential to cause a work explosion.

    It is probably considered obvious, but I did not see text indicating that GRASP messages with unknown MESSAGE_TYPE should be silently ignored.  Or any other definition of the expected behavior (should be logged?)

Nits/editorial comments: 
    In section 3.1 in the definition of Technical Objective the text starts by saying that it is a configurable parameter or set of parameters.   Most further text refers to a single value, with indications that the value may be a complex structure.  Hence, in the first part of the definition, the same construction should be used, rather than referring to a set of values.  This gets slightly confused when section 3.10.4 goes back to talking about multiple parameters for an objective.  Consistency please?

    The first paragraph of 3.5.4.1 states that upon receiving a discovery request, a recipient will respond, either with the data or with a divert.  While this is eventually true, it is misleading.  As 3.5.4.2 states, the recipient, if it does not have an answer, will relay the request in order to get an answer.  Some mention of this in 3.5.4.1 would seem helpful.

    Should the first line of 3.5.5 on negotiation include "(using M_REQ_NEG)"?