Re: [Isis-wg] WG Last Call for draft-ietf-isis-reverse-metric-07

["t.petch" <[e-mail]>]

Naiming

One follow-up comment inline

Tom Petch

---- Original Message -----
From: "Naiming Shen (naiming)" <[e-mail]>
Sent: Saturday, January 06, 2018 12:31 AM

> Hi Tom,
>
> Thanks for the review, some replies inline,
>
> On Dec 29, 2017, at 2:53 AM, t.petch
<[e-mail]<mailto:[e-mail]>> wrote:
>
> A couple of IANA thoughts on this I-D;
>
> "This document requests that IANA allocate from the IS-IS TLV
>   Codepoints Registry a new TLV, "
>
> - Is there a particular range that this value should come from?
>
> NS> will add the range.
>
>
> - A note in s.2 asking that TBD be replaced by the value that IANA
> allocates might be useful for the RFC Editor.
>
> NS> will do.
>
>
> - Are the flag bits of this new TLV going to form a new registry?
>
> NS> it is not.
>
>
> - And a non-IANA thought - what does a receiver do if it receives more
> than one such TLV?
>
> NS> In section 2, it mentions "A sender MUST only transmit a single
>      Reverse Metric TLV in a IS-IS Hello PDU.”

I know it does, but I also know that we cannot rely on all
implementations being perfect:-)

Look at some other RFC (e.g. RFC5029) and you will find an action
defined such as subsequent ones will be ignored, or perhaps that this
should be treated as a fatal error or ..  I suggest something similar
here although have no strong views what the action should be.

Tom Petch

> "This document also request that IANA allocate from the link-attribute
>   bit value for sub-TLV 19 of TLV 22."
> I struggled to parse this initially.
>
> Perhaps
> "This document also requests that IANA allocate a bit from the
> 'link-attribute bit values for sub-TLV 19 of TLV 22' registry.
>
>
> NS> OK.
>
> (That registry title is a bit of a mouthful compounded by the lack of
> Capitals in the title:-(
>
> The coupling between the request to IANA to allocate the bit and the
> actual definition in the body of the I-D is ... well, non-existent.
You
> should have a something about the octet with a TBD2 (not a second TBD)
> in section 3.6, a TBD2 in the IANA actions and a request that this be
> replaced by RFC Editor by the value that IANA allocates.
>
>
> NS> will do.
>
> thanks.
> - Naiming
>
> Yes, a reader can deduce all this but the lack of precision is how
> mistakes are made IMO.  RFC5209 has the sort of detail that I would
> expect.
>
> Tom Petch
>
> ----- Original Message -----
> From: "Naiming Shen (naiming)"
<[e-mail]<mailto:[e-mail]>>
>
>
>