Last Call Review of draft-ietf-6lo-fragment-recovery-08
review-ietf-6lo-fragment-recovery-08-genart-lc-yee-2020-02-01-00

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Document: draft-ietf-6lo-fragment-recovery-08
Reviewer: Peter Yee
Review Date: 2020-02-01
IETF LC End Date: 2020-01-30
IESG Telechat date: Not scheduled for a telechat

Summary: This draft is a clearly-written Standards Track specification for how
to do fragment recovery in a 6LoWPAN mesh network.  The document has some minor
issues and numerous nits that should be addressed prior to publication. [Ready
with Issues]

Apologies for the timely review. Sigh. ;-)

Major issues:  None

Minor issues:

Page 9, 1st paragraph after Figure 1, 1st sentence: how does the sender ensure
the full reception of the datagram?  It can assume that to be the case, but
there's no further mechanisms available to it to "ensure" anything beyond that.

Page 13, 4th full paragraph, 1st sentence: the receiver is instructed send an
RFRAG Acknowledgment without regard to whether the sender wishes to protect the
datagram, in contradiction to the 2nd sentence in the 4th preceding paragraph
(which starts on the bottom of page 12).  Try to rationalize the two
paragraphs.  Also, what constitutes a "short" timer?  How is an implementer to
decide what's reasonable?

Page 14, 2nd full paragraph, 1st sentence: how is a "reasonable" amount of time
calculated?

Nits/editorial comments:

General:

Change "en-route" to "en route".

Append a comma after each occurence of "i.e.".

Specific:

Page 2, Section 1, 1st sentence: change "in" to "on".  Append "of a" after
"order".

Page 3, 1st full paragraph, 2nd sentence: change "to reassemble" to
"reassembling".

Page 3, 1st full paragraph, 3rd sentence: change "to use" to "using".

Page 3, 2nd full paragraph, 4th sentence: insert "on" before "pages".

Page 3, 2nd full paragraph, last sentence: change "can not" to "cannot".

Page 4, 1st partial paragraph, 1st full sentence: change "to a" to "in".

Page 4, section 2.2, 3rd paragraph, 1st sentence: insert "the" before
"application".

Page 6, section 3, 1st paragraph, last sentence: change "fragment" to
"fragments".

Page 6, section 3, 2nd paragraph, 1st sentence: change "to modify" to
"modifying".

Page 6, section 3, 2nd paragraph, 2nd sentence: change "It results" to "This
requires".  Change "whcih" to "which".

Page 6, section 3, 2nd paragraph, 3rd sentence: change "to modify" to
"modifying".

Page 6, section 3, 3rd paragraph: change "consistently" to "consistent". 
Append a comma after "[RFC6282]".

Page 7, section 4.1, 1st paragraph, 1st sentence: consider eliding "At the time
of this writing, ".  If the other draft's final position can be clarified
before publication of this draft, it's redundant.  If it's not clear at time of
publication of this draft than it's a guess.

Page 7, section 4.1, 1st paragraph, 2nd sentence: change "to happen" to
"happening".

Page 7, section 4.2, 1st paragraph, 1st sentence: insert "an" before
"Inter-Frame".  Consider whether "Inter-Frame Gap" should be written the same
as subsequent usage ("InterFrameGap") and if you choose not to do so, perhaps
make it "inter-frame gap" since it is a concept, not a name.

Page 7, section 4.2, 1st paragraph, 2nd sentence: consider changing
"progressed" to "processed" or "completed processing of".

Page 7, section 4.3, 1st paragraph, 1st sentence: delete the comma after
"Routing Header".

Page 8, section 5, 2nd paragraph, last sentence: change "It" to "the" and
insert an "i" before "s".

Page 8, section 5.1, 1st sentence: change "on" to "with respect to".  Change "-
native -" to "(native)".

Page 10, RFRAG Header names: try to capitalize these consistently amongst
themselves or at least consistently with Figure 1.

Page 10: Fragment_size, 1st sentence: change "10 bit" to "10-bit".

Page 10, Fragment_size, 2nd sentence: append a comma after "octet".

Page 10, Sequence, 1st sentence: change "5 bit" to "5-bit".

Page 10, Fragment_offset: change "16 bit" to "16-bit".

Page 10, Fragment_offset, 4th bullet item, 1st sentence: append a comma after
"6.1.1.".

Page 10, Fragment_offset, 4th bullet item, 2nd sentence: delete "as".

Page 11, section 5.2, 1st paragraph, 2nd sentence: change "one to one" to
"121".  No, actually I mean "one-to-one".  ;-)

Page 11, 1st paragraph after Figure 3: change "a" to "an" before "RFRAG".

Page 12, RFRAG Acknowledgment Bitmap, 2nd sentence: delete the first instance
of "that".

Page 12, RFRAG Acknowledgment Bitmap, 3rd sentence: delete the first instance
of "that".  Change the comma to a semicolon.

Page 12, section 6, 1st paragraph, 2nd sentence: delete the extraneous space
before "with".

Page 12, section 6, 1st paragraph, last sentence: change "associated to" to
"associated with".

Page 12, section 6, 2nd paragraph, 1st sentence: insert "the" before "6LoWPAN".

Page 12, section 6, 2nd paragraph, 5th sentence: insert "the" before "6LoWPAN".

Page 13, 1st partial paragraph, 1st full sentence: expand the use of "ARQ" here
and put "ARQ" in parenthesis, or put "(ARQ)" before a prior use of
"Ack-Request".  Append "for" after "out".  Change "amount" to "number".

Page 13, 2nd full paragraph, 2nd sentence: change "preceeding" to "preceding".

Page 13, 2nd full paragraph, last sentence: change "round trip" to "round-trip".

Page 13, 3rd full paragraph, last sentence: append "the sender" after "inform".
 Change "process" to "processing".

Page 13, 4th full paragraph, 1st sentence: change "a" to "an" after "sends". 
Insert "to" before "abort".  Consider changing "reasonable time" to "the
duration of the timer".  Also, this is one really long sentence.  Perhaps you
could break it down?

Page 14, 1st full paragraph, 1st sentence: change "round robin" to
"round-robin".

Page 14, section 6.1, 1st paragraph: change "Fragment" to "fragment".

Page 14, section 6.1, 2nd paragraph, 2nd sentence: change "Switching" to
"switching".

Page 14, section 6.1, 2nd paragraph, 3rd sentence: delete "In more details, "
and change the first "the" to "The".

Page 14, section 6.1, 2nd paragraph, 4th sentence: append "receiving" after
"Upon".

Page 14, section 6.1, 2nd paragraph, 6th sentence: change "that" to "which".

Page 14, section 6.1, 2nd paragraph, last sentence: change "at" to "in".

Page 14, section 6.1.1: change "Upon" to "Receiving" or perhaps append
"receiving" after "Upon".

Page 14, section 6.1.1., 1st paragraph, 2nd sentence: change "to" to "with"
after "associated".  Append "address" after each "MAC".

Page 14, section 6.1.1., 1st paragraph, 3rd sentence: append "receiving" after
"Upon".

Page 15, 1st partial paragraph: change "whereas" to "where".

Page 15, 1st full paragraph, 1st sentence: change "to match" to "matching".

Page 15, 1st full paragraph, 2nd sentence: change "Reverse" to "reverse".

Page 15, 1st full paragraph, 3rd sentence: change "to match" to "matching".

Page 15, 2nd full paragraph, 3rd sentence: insert "determine whether to" before
"abort".

Page 15, section 6.1.2: Change "Upon" to "Receiving" or append "receiving"
after "Upon".

Page 15, section 6.1.2, 1st paragraph, 1st sentence: append "receiving" after
"Upon".

Page 15, section 6.1.2, 2nd paragraph: change "if" to "If".

Page 15, section 6.1.2, 2nd bullet item: insert "is" before "set".

Page 16, 1st partial paragraph, 1st full sentence: change "in" to "is".

Page 16, section 6.2: change "Upon" to "Receiving" or append "receiving" after
"Upon".  Drop "the" if you like.

Page 16, section 6.2, 1st paragraph, 1st sentence: append "receipt of" after
"Upon".

Page 16, section 6.3, 1st paragraph: append a comma after "sequence".

Page 17, 1st paragraph: change "to" to "with" after "associated".

Page 17, 2nd paragraph, 3rd sentence: change "frowarded" to "forwarded".

Page 18, OptARQTimeOut: append "of time" after "amount".

Page 18, MaxFragRetries: change "Fragment" to "fragment".

Page 18, MaxDatagramRetries: change "Datagram" to "datagram".

Page 19, section 7.2, 1st sentence: delete "the" before "both".  Change the
first "OptWindowSize" to "OptDatagramSize".

Page 19, section 7.2, last sentence: change "a same" to "the same".

Page 19, section 8, 2nd paragraph, 2nd sentence: change "reducing" to "being
reduced".

Page 19, section 8, 2nd paragraph, last sentence: delete "ot" [sic].  Change
"clean" to "cleaning".

Page 19, section 8, 3rd paragraph, 3rd paragraph, 2nd sentence: change "to
realign" to "realigning".  Append a comma after "fragment".

Page 20, section 10, 1st sentence: append a comma after "Watteyne".

Page 20, section 10, 2nd sentence: append a comma after "Bormann".

Page 25, Appendix B, 1st paragraph, last sentence: change "a" to "an" before
"LLN".

Page 25, individual requirements: append a colon after the name of each
requirement, e.g., "Number of fragments:".

Page 25, Minimum acknowledgment overhead: insert "a" before "data".

Page 26, Appendix C: change "On" to "on".

Page 26, Appendix C, 2nd paragraph, 2nd sentence: change "to control" to
"controlling".  Delete the comma after "fragments".

Page 26, Appendix C, 4th paragraph, 3rd sentence: delete "an" before
"end-to-end".

Page 26, Appendix C, 4th paragraph, last partial sentence: change "TimeSlotted"
to "Time-Slotted".