Last Call Review of draft-ietf-hip-dex-06

Request Review of draft-ietf-hip-dex
Requested rev. no specific revision
Type Last Call Review
Team General Area Review Team (Gen-ART) (genart)
Deadline 2018-02-26
Requested 2018-02-12
Other Reviews Secdir Last Call review of -06 by David Waltermire
Opsdir Last Call review of -06 by Qin Wu
Review State Completed
Reviewer Francis Dupont
Review review-ietf-hip-dex-06-genart-lc-dupont-2018-02-26
Posted at
Reviewed rev. 06
Review result Ready
Draft last updated 2018-02-26
Review completed: 2018-02-26


I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.  Please treat these comments just
like any other last call comments.

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Document: draft-ietf-hip-dex-06.txt
Reviewer: Francis Dupont
Review Date: 20180224
IETF LC End Date: 20180226
IESG Telechat date: unknown

Summary: Ready

Major issues: None

Minor issues: None

Nits/editorial comments: 
 - ToC page 3: you use the US spelling of Acknowledgments in the ToC
  and the English one (acknowledgements) in the technical body.
  Even when it is not very consistent I believe this follows RFC 7401
  choice so I am fine with this.

 - 2.1 page 6: please add/move to RFC 8174 which updates RFC 2119 fixing
  the keyword case silly issue.

 - 2.2 page 6: perhaps "sort" should be added here?

 - 2.3 page 7 (twice): (c.f.  Section 3)  -> (see Section 3) or
  simply (Section 3)

 - page 16 (at end of line): e.g. -> e.g.,

 - 5.3.3 page 25: I don't believe the critical property for
  random value is to be "uniformly distributed" (for instance
  I could have put "unpredictable"). I leave this to the security
  directorate who should propose a better wording if they don't like
  the current one...

 - 5.3.4 page 26: same comment.

 - 6.1 page 27: this section does not really explain what is the puzzle
  (it only stands the equation to verify) but I remember the explaination
  was before with a reference to 6.1 so I have no concern.

 - 6.2.1 sender 3 page 27: hidden dependency on the sort definition
  for HOST_g/HOST_l so gl/lg keys. Yes it is in 6.3 but 6.3 is after.

 - 6.3 pages and 30: sort is used page 29 and defined after page 30,
  this is why IMHO the question to move the definition to 2.2 notation
  is a good one...

 - 6.3 page 30: / is not associative so ceil(L/RHASH_len/8) is bad.
  The text shows it must be ceil(L/(RHASH_len/8)) (vs ceil((L/RHASH_len)/8))

 - 6.5 1. page 31: Otherwise, it must drop the packet. -> MUST

 - 6.6 1. page 33: the system should process the R1 packet -> or SHOULD
  or (I prefer) the system processes the R1 packet

 - 6.6 8. page 34: The R1 packet may have the A-bit set -> can
  (not better from a language point of view but clearer and BTW
   used for instance in 6.10...)

 - 6.6 13. page 34: it may either resend an I1 packet -> MAY? (cf 11.)

 - 6.7 5. page 36: Otherwise, the system should process the received I2 ->
  or SHOULD or (better) processes (and drop -> drops)

 - 6.7 15. page 37:
     If the A-bit is set, the Initiator's HIT is anonymous and should
     not be stored permanently. -> IMHO SHOULD NOT or directly MUST NOT

 - 6.9 page 39: If a NOTIFY packet is received in state I2-SENT, this
   packet may be an I2 reception acknowledgement of the optional
   -> replace "may be" by "can be" or (better) "is"

 - 7 page 40: Please put "If a Responder is not under high load, #K
   SHOULD be 0." in its own paragraph (i.e. add a break before "If").
   It makes clearer this sentence is a requirement when the text before
   is the rationale.

 - 8 page 40: " either supports HIP DEX or HIPv2 must be able to detect"
  -> MUST or "has to"

 - 8 pages 40 and 41: I think that the first and last paragraphs of
  section 8 say the same thing. Should you keep both?

 - 9 page 41: I'd like to see a formal proof of the DEX protocol.
  I believe you share this wish as you cite SIGMA.

 - 9 page 42: I'd like to go further and recommend (lower case) the
  use of a RNG (vs PRNG) when available (hopefully no longer an exception).

 - 9 page 42: Hence, HIP DEX HITs should not be use -> SHOULD or
  ought to?