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Last Call Review of draft-ietf-detnet-bounded-latency-08
review-ietf-detnet-bounded-latency-08-intdir-lc-weber-2022-02-06-00

Request Review of draft-ietf-detnet-bounded-latency
Requested revision No specific revision (document currently at 10)
Type Last Call Review
Team Internet Area Directorate (intdir)
Deadline 2022-02-08
Requested 2022-01-26
Requested by Éric Vyncke
Authors Norman Finn , Jean-Yves Le Boudec , Ehsan Mohammadpour , Jiayi Zhang , Balazs Varga
I-D last updated 2022-02-06
Completed reviews Rtgdir Last Call review of -06 by Tony Przygienda (diff)
Genart Last Call review of -08 by Gyan Mishra (diff)
Intdir Last Call review of -08 by Ralf Weber (diff)
Secdir Last Call review of -08 by Watson Ladd (diff)
Artart Last Call review of -08 by Robert Sparks (diff)
Tsvart Last Call review of -08 by Yoshifumi Nishida (diff)
Secdir Telechat review of -10 by Watson Ladd
Assignment Reviewer Ralf Weber
State Completed
Review review-ietf-detnet-bounded-latency-08-intdir-lc-weber-2022-02-06
Posted at https://mailarchive.ietf.org/arch/msg/int-dir/3l_mAv_wK4p470EYFiDAkR5mghA
Reviewed revision 08 (document currently at 10)
Result Ready w/nits
Completed 2022-02-06
review-ietf-detnet-bounded-latency-08-intdir-lc-weber-2022-02-06-00
Moin!

I am an assigned INT directorate reviewer for draft-ietf-detnet-bounded-latency.
These comments were written primarily for the benefit of the Internet Area
Directors. Document editors and shepherd(s) should treat these comments just
like they would treat comments from any other IETF contributors and resolve
them along with any other Last Call comments that have been received. For more
details on the INT Directorate, see
https://datatracker.ietf.org/group/intdir/about/

The draft is very detailed, well written and covers the subject exhaustively. I
think it is ready for publication.

The biggest problem I had was reading all the formulas, that because of the
limitations of being published as an RFC can't be printed nice as you would see
them in a math book. And while they are correct (with one exception) I think
they would be more readable if they had parentheses for groups especially when
going over multiple lines like e.g on page 13:

      backlog_bound = nb_input_ports * max_packet_length + total_in_rate
      * max_delay456

IMHO would be nicer as:

      backlog_bound = ( nb_input_ports * max_packet_length  ) +
                                  ( total_in_rate * max_delay456 )

there is on error on page 19 where the opening parentheses is missing:

      T_A = L_nA + b_h + r_h * L_n/c)/(c-r_h)

could be:

      T_A = ( L_nA + b_h + ( r_h * L_n/c )) / ( c-r_h )

or at least has to be:

      T_A = (L_nA + b_h + r_h * L_n/c)/(c-r_h)

we may have rules formulas in the IETF for this which might be different from
my examples and if we do we should of course follow them, but at least I don't
know of them.

Another nit was that on page 10 there is a description of a T-Spec (Traffice
Specification) of a DeNet flow that is defined in RFC9016 as:
        "Interval: tau, MaxPacketsPerInterval: K, MaxPacketSize: L"
however using the terms defined in RFC9016 section 5.5 it should be:
        "Interval: tau, MaxPacketsPerInterval: K, MaxPayloadSize: L"

Overall I'd like to thank the authors for a very well written document.

So long
-Ralf