Re: [Ntp] Robert Wilton's Discuss on draft-ietf-ntp-interleaved-modes-05: (with DISCUSS and COMMENT)

["Rob Wilton (rwilton)" <[e-mail]>]

Hi Miroslav,

Sorry for the slow response.  I was hoping that this document would be discussed on a telechat to see whether my concerns were shared by other ADs.

Regarding the issue with the extension mechanism, another possible choice could be for the client to try and open two parallel sessions, one using a new extension field, and one without.  The client could then monitor the responses to the two sessions and choose whether to use the other with the extension or not.

However, I'm not sure whether this would really help you.  I might be misunderstanding the situation here, but it seems that this draft is partially documenting what quite a few NTP servers already do, and hence inventing a new mechanism might not really help.  But certainly if a lots of implementations are already doing this, then documenting that is helpful, and worth doing.

Hence, I propose three possible alternatives:

(1) Change this document to somehow make use of NTPs extension mechanism and continue down the path of publishing as a proposed standard.  This, I think, would probably entail taking the document back to the WG.

(2) Change the document status to Informational rather than Standards Track, modifying the text to focus on documenting how some implementations work rather than as an endorsement from IETF that this is the right way to modify the NTP protocol.

(3) Alternatively, if the authors/WG believe that publishing that document as proposed standard is definitely the right choice, then I would be willing to change my ballot position to abstain.  I.e., I don't agree with what is being done here, but neither will I block progression of the document, given that you say that this modification does not cause operational issues in practice.

Regards,
Rob


> -----Original Message-----
> From: Miroslav Lichvar <[e-mail]>
> Sent: 01 July 2021 16:06
> To: Eric Vyncke (evyncke) <[e-mail]>; Warren Kumari
> <[e-mail]>; Rob Wilton (rwilton) <[e-mail]>
> Cc: The IESG <[e-mail]>; [e-mail]; ntp-
> [e-mail]; [e-mail]; [e-mail]
> Subject: Re: [Ntp] Robert Wilton's Discuss on draft-ietf-ntp-interleaved-
> modes-05: (with DISCUSS and COMMENT)
> 
> On Wed, Jun 30, 2021 at 11:46:36AM +0200, Miroslav Lichvar wrote:
> > On Tue, Jun 29, 2021 at 11:09:27AM +0000, Rob Wilton (rwilton) wrote:
> > > Section 2 of the draft states:
> > >
> > >    The origin timestamp is a cookie, which is used to detect a packet
> > >    which is not a response to the last packet sent in the other
> > >    direction.  Such packets are called bogus packets in RFC 5905.
> >
> > I can see how this paragraph is confusing. It was a late addition. It
> > should be improved. Bogus packets are responses, not requests.
> 
> This should be now fixed in the new version of the draft, together
> with the issues pointed out by Éric and Warren.
> 
> Please let me know if you think it's insufficient or you see other
> issues.
> 
> https://www.ietf.org/rfcdiff?url2=draft-ietf-ntp-interleaved-modes-06
> 
> Thanks,
> 
> --
> Miroslav Lichvar