Early Review of draft-ietf-tsvwg-circuit-breaker-11
review-ietf-tsvwg-circuit-breaker-11-rtgdir-early-malis-2016-02-08-00

Hello,

I have been selected as the Routing Directorate reviewer for this draft. The
Routing Directorate seeks to review all routing or routing-related drafts as
they pass through IETF last call and IESG review, and sometimes on special
request. The purpose of the review is to provide assistance to the IESG. For
more information about the Routing Directorate, please see ​

http://trac.tools.ietf.org/area/rtg/trac/wiki/RtgDir

It would be helpful if you could consider these comments along with any other
IETF Last Call comments that you receive, and strive to resolve them through
discussion or by updating the draft.

Document: draft-ietf-tsvwg-circuit-breaker-11.txt

Reviewer: Andy Malis

Review Date: February 5, 2016

IETF LC End Date: February 9, 2016

Intended Status: Best Current Practice

Summary:

I have some minor concerns about this document that I think should be resolved
before publication.

Major Issues:

No major issues found.

Minor Issues:

Page 3, first paragraph: There are no citations to the claim that
non-congestion-controlled traffic "can form a significant proportion of the
total traffic traversing a link". Sure, video is a major part of Internet
traffic these days, but much Internet video is dynamically adaptive. One or
more citations would be useful.

Section 4: There are so many issues that they should be numbered, so that they
can be referred to individually (from another document, for example).

Page 11: In my opinion, the second and third requirements on this page should
be "MUST"s rather than "SHOULD"s.

Page 12, discussion of "In-Band" near the bottom of the page: This paragraph
implies that an in-band control method will always provide fate-sharing of the
control and regular traffic. It may provide fate-sharing, but that is by no
means assured. For example, the network may be using ECMP, or traffic tunnels
for data but not control traffic.

Section 5: I'm not sure why Section 5 is a separate section, and not integrated
into Section 3 as new subsections, which I think would be an improvement.

Page 13, first paragraph: "presented in figure 2" -> "presented in figures 1
and 2".

Page 19, fourth paragraph: This paragraph states that "IP-based traffic is
generally assumed to be congestion-controlled". This is true for TCP-based
traffic, but I would not make such an assumption for all IP-based traffic.

Nits:

The abbreviation "CB" is defined early in the document, but is hardly if ever
used thereafter, rather "Circuit Breaker" is almost always spelled out. It may
be useful to actually use the abbreviation.

Page 3, first paragraph, fifth line, "connection" -> "connections".

Figure 1: Move the vertical line between the "Measure" and "Trigger" boxes one
space to the right.

Page 10, fourth paragraph: "If necessary, MAY combine" -> "If necessary, a CB
MAY combine".

Page 11, fifth paragraph: "needs to be" -> "MUST"

Page 12, second paragraph: There are two separate references to Section 8. One
combined reference should be sufficient.

Page 12, second to last paragraph: "in-Band" should have the "i" capitalized.

Page 15, last paragraph: "tranport" -> "transport"

Page 17, fifth paragraph: "Pseudo Wire" -> "PW"

Regards,

Andy