[Lsr] Pre-writeup review comments

Christian Hopps <chopps@chopps.org> Fri, 18 September 2020 14:08 UTC

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From: Christian Hopps <chopps@chopps.org>
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Date: Fri, 18 Sep 2020 10:08:08 -0400
Cc: Christian Hopps <chopps@chopps.org>, lsr@ietf.org
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Subject: [Lsr] Pre-writeup review comments
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During my review and while doing the Shepherd writeup for https://datatracker.ietf.org/doc/draft-ietf-lsr-isis-srv6-extensions/ I came up with the following comments:


4.3 - Maximum H.Encaps MSD Type:

  - what is the default if not advertised?

6.  Advertising Anycast Property

Should "Locator that is advertised..." be:

  "An SRv6 Locator that is advertised..."?

or:

  "A prefix/SRv6 Locator that is advertised..."?

7.1 SRv6 Locator TLV Format

The R fields and their handling, are not defined.

8.  Advertising SRv6 Adjacency SIDs

"must be" "in order to be correctly applied" -> "are" and ""?

8.1.  SRv6 End.X SID sub-TLV

"Other bits" -> "Reserved bits" -- labels should match

8.2.  SRv6 LAN End.X SID sub-TLV

I'm sympathetic to Bruno's comment, and so I think it would be better to say:

Diagram: "System ID (1-6 octets)" and in text:

"6 octets" -> "System ID: 1-6 octets"

I see no reason to mess with this even if the commonly-implemented value is 6 at
this point. IS-IS implementations that only support 6 octets are free to only
support 6 in this sub-TLV as well. They won't be talking with other IS-IS
routers that are configured to have a non-6 octet system ID value. What other
extension RFCs may or may-not do WRT this doesn't really matter I think.

"Other bits" -> "Reserved bits" -- labels should match

11.  Implementation Status

Does this section need a "RFC Ed.: Please Remove prior to publications"? It
seems pretty wrong to document current status of implementations permanently in
an Standards Track RFC.

12. IANA Considerations

An odd space between "sub- TLV".

12.5.  Sub-Sub-TLVs for SID Sub-TLVs

This section needs to better conform to registry creation standards (see
https://tools.ietf.org/html/rfc8126).

ID-NITS:

  There are 19 instances of too long lines in the document, the longest one
  being 5 characters in excess of 72.

References:
  Normative:
    Published: RFC 8754 draft-6man-segment-routing-header
    Out of date reference: [I-D.ietf-6man-spring-srv6-oam]
    Out of date reference: [I-D.ietf-spring-srv6-network-programming]
  Informative:
    Published: RFC 8402 draft-ietf-spring-segment-routing