[spring] Barry Leiba's No Objection on draft-ietf-spring-srv6-network-programming-19: (with COMMENT)

[Barry Leiba via Datatracker <[e-mail]>]

Barry Leiba has entered the following ballot position for
draft-ietf-spring-srv6-network-programming-19: No Objection

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COMMENT:
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Throughout the document:
It should be “an SID”, “an FIB”, “an RIR”, and some others, not “a”, because
one reads these as “ess-eye-dee” and “eff-eye-bee”, not as the expansions
thereof.

— Section 3.1 —

   An SRv6 endpoint behavior MAY require additional information

I think this is a statement of fact, so “may” (or “might”), not “MAY”.

— Section 3.2 —
Nit: The plural of “SID” is “SIDs”, without an apostrophe.

   The provider historically deployed IPv6 and assigned
   infrastructure address from a portion of the fc00::/7 prefix

Nit: “addresses”.

   In another example, a large mobile and fixed line service provider

Nit: hyphenate “fixed-line”.

   IPv6 address consumption in both these examples is minimum,

Nit: “minimal” (also, put a comma before “respectively”).

   A remote node uses the IANA behavior codepoint to map the received
   SID (B:N:FUNCT) to a behavior.

I don’t know what “IANA behavior codepoint” means.  As the rest of the sentence
makes it clear that this is mapping to “a behavior”, maybe it’s better to say
“registered codepoint”, or some such?  Or, as you say a couple of paragraphs
down, “Endpoint Behavior codepoint”?  In any case, please be consistent about
“IANA behavior”, “IANA Behavior”, and “IANA Endpoint Behavior”.  My preference
would be to avoid saying “IANA” in these, but use your judgment on what’s most
understandable and clear.

   o  Assign an SRv6 Locator 2001:db8:bbbb:3::/64 to the Router 3 in
      their SR Domain

What is “the Router 3” (and router 4)?  There’s no introduction nor diagram
that says.  Also, please be consistent in capitalization of these.

— Section 3.3 —

   routing protocol specific aspects that are outside the scope of this

Nit: “routing-protocol-specific” needs to be hyphenated.  As that’s awkward,
you might want to reword to avoid it, “are specific to the routing protocol and
are outside the scope....”

— Section 4 —

   The pseudocode describing these behaviors detail local processing

Nit: “details”, singular, to match “pseudocode”.

— Section 4.1 —

   The End behavior operates on the same FIB table (i.e.  VRF, L3 relay
   id) associated to the packet.

Is “i.e.” really what you want here?  How does “VRF, L3 relay” equate to “FIB
table”?

— Section 4.16.1.3 —

   segments left to 0.  The SDN controller knows that no-other node

Nit: “no other” should not be hyphenated.  For that matter, the word “other”
isn’t needed anyway, because you have “after” in there.

   -as part of the decapsulation process the egress PE is required to
    terminates less bytes from the packet.

I can’t figure this out.  It looks like it should be “required to terminate”,
but I don’t know what it means to “terminate less bytes”.  Can you reword this?

    to the lookup engine in the forwarding ASIC.

“ASIC” needs to be expanded.  As this is the only place you use it, I suggest
just using the expansion and not bothering with the abbreviation.

— Section 7 —

   This document introduces SRv6 Endpoint and SR Policy Headend
   behaviors for implementation on SRv6 capable nodes in the network.
   As such, this document does not introduce any new security
   considerations.

I’m not convinced of this.  It seems that misuse (such as injection or
alteration) of some of these Behaviors could, for example, result in packets
being forwarded to nodes they were not intended to go to.  Is it not important
to discuss issues such as that: how these Behaviors might be attacked?  Is that
really fully covered in 8754 and 8402?

— Section 8.1 —

   The presence of SIDs in the IGP do not imply any routing semantics

Nit: “does not”, to match the singular subject “the presence”.

   an IPv6 address is solely governed by the, non-SID-related, IGP

Nit: remove both commas.

   not governed neither influenced in any way by a SID advertisement

Nit: make it “neither governed nor influenced”

   build TI-LFA [I-D.ietf-rtgwg-segment-routing-ti-lfa] based FRR
   solutions

Nit: there needs to be a hyphen in there, but the citation gets in the way. 
Make it, “build FRR solutions based on TI-LFA
[I-D.ietf-rtgwg-segment-routing-ti-lfa]”.

— Section 8.4 —

   For example, a BGP-LS advertisement of H.Encaps behavior would
   describe the capability of node N to perform a H.Encaps behavior,
   specifically it would describe how many SIDs could be pushed by N
   without significant performance degradation.

This is a comma splice.  Split the sentence before “specifically” (and put a
comma after “specifically”).