I have been selected as the General Area Review Team (Gen-ART)
reviewer for this draft (for background on Gen-ART, please see
http://www.alvestrand.no/ietf/gen/art/gen-art-FAQ.html).
Please wait for direction from your document shepherd
or AD before posting a new version of the draft.
Document: draft-ietf-ipfix-export-per-sctp-stream-06
Reviewer: Ben Campbell
Review Date: 1 March 2010
IESG Telechat date: 4 March 2010
Summary: This document is almost ready for publication as a proposed standard,
but there is an open issue that should be considered first.
Major issues:
-- section 4.5, general:
I am confused as to how the collector determines the exporter supports this
extension. If I understand correctly (and it's probable that I do not, since
this is my first real exposure to IPFix), the collector basically has to infer
exporter support from the behavior of the exporter. But then the second
paragraph after the numbered list (i.e. 2 paragraphs after item 4) says:
"In the case where the Exporting Process does not support the
per-SCTP-stream extension, then the first Data Record received
by the Collecting Process will disable the extension for the
specific Exporter on the Collecting side."
This seems to conflict. Why would the collector need to worry about items 1-4
if it can categorically determine exporter support from the first data record?
In general, though, I think that having the collector infer support is not the
right way to do this. It would be far better to explicitly signal support, if
that is at all possible in IPFix. Otherwise, it seems like the collector has to
watch every record for violations of 1-4, and make fairly complex decisions on
a per-record basis.
Minor issues:
-- section 4.2, 3rd paragraph from end, starting with "When an Options
Template..."
I'm confused by this paragraph. Would exporters using this extension ever send
the options template and associated data records in different streams?
Nits/editorial comments:
-- section 4.1, description of dataRecordsReliability:
I find the first sentence hard to parse.
-- section 4.2, first paragraph" "...exporting processes should follow..."
(Note that an identical comment applies to the first paragraph of several of
the specification sections.)
It would be best to avoid the word "should" in this context. Even though we all
know a lower case should is not normative, it's still enough to confuse a
reader into interpreting as a normative SHOULD, which is actually weaker than
the real requirement. That is, I don't think you mean to say that, in order to
take advantage of this extension and implementation SHOULD follow this
specification.
-- section 4.3, paragraph 3:
pedantic nit - I think you mean all IPFIX messages in a single stream MUST be
sent in order--not that all messages have to be in a single stream, right? The
current wording is (slightly) ambiguous on that point.
-- section 4.3, last paragraph:
Why mention the alternative if it is not feasible in production?
--Examples, figure 3:
Is Data 257 a typo?
-- idnits has some warnings. Please check before publication.
_______________________________________________
Ietf mailing list
Ietf(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf