Last Call Review of draft-ietf-ospf-segment-routing-extensions-19
review-ietf-ospf-segment-routing-extensions-19-genart-lc-romascanu-2017-10-05-00

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Document: draft-ietf-ospf-segment-routing-extensions-19
Reviewer: Dan Romascanu
Review Date: 2017-10-05
IETF LC End Date: 2017-10-13
IESG Telechat date: Not scheduled for a telechat

Summary:

A useful and well-written document. It requires previous reading and
understanding of OSPF, SPRING and other routing work. It is Ready for
publication. I found some unclear minor issues. I recommend to address them
before approval and publication.

Major issues:

Minor issues:

1. I am wondering why, at this stage of progress of the document, the type
values are still 'TBD, suggested value x'. Is there any other document defining
this?

2. Section 3.1 - are there other algorithms planned to be added in the future?
If yes, do we need a registry? If no, what is this field an octet?

3. It would be useful to mention that the Length fields are expressed in
Octets. Also please clarify if padding is applied or not.

4. Section 3.3:

'The originating router MUST NOT advertise overlapping ranges.'

How are conflicts resolved at receiver?

5. I like Section 9 - Implementation Status - which I found rather useful. Is
there any chance to keep a trimmed down version of it, with synthetic
information on the lines of 'at the time the document was discussed a survey
was run, it showed that there were x implementation, y were implementing the
full specification, z were included in released production software ....'

6. Section 10 - beyond recommending the counting and logging of the mal-formed
TLVs and sub-TLVs, should not supplementary security recommendations be made?
for example - throttling mechanisms to preempt DoS attacks.

Nits/editorial comments: