Subject: [Ntp] Éric Vyncke's No Objection on draft-ietf-ntp-interleaved-modes-05: (with COMMENT)

From: Éric Vyncke via Datatracker <[email-masked]>
Date: Mon, 28 Jun 2021 04:07:51 -0700

Éric Vyncke has entered the following ballot position for
draft-ietf-ntp-interleaved-modes-05: No Objection

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COMMENT:
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Thank you for the work put into this document. I really like the idea behind
this I-D: simple and smart ;-)

Please find below some non-blocking COMMENT points.

I hope that this helps to improve the document,

Regards,

-éric

-- Section 2 --
"  The server MAY separate the timestamps
   by IP addresses, but it SHOULD NOT separate them by port numbers,
   i.e.  clients are allowed to change their source port between
   requests."
With draft-ietf-ntp-port-randomization in mind, please change the "clients are
allowed" into "clients are recommended to"

"  Both servers and clients that support the interleaved mode MUST NOT
   send a packet that has a transmit timestamp equal to the receive
   timestamp"
Will it always be possible to comply with the above "MUST NOT" ?

---

From: Miroslav Lichvar <[email-masked]>
Date: Mon, 28 Jun 2021 16:11:58 +0200

> draft-ietf-ntp-interleaved-modes-05: No Objection

Thanks for the review.

> allowed" into "clients are recommended to"

If I didn't miss an update in the recent changes of the draft, the
port-randomization draft still leaves that per-request or
per-association decision to the implementation with no preference, so
I think they can but are not recommended to change the port between
requests.

> Will it always be possible to comply with the above "MUST NOT" ?

I think it will. If the timestamps happen to be equal, one of the
timestamps can simply be adjusted by 1 before the transmission. That's
~1/4 of nanosecond, well hidden in the typical precision of an NTP
clock.

-- 
Miroslav Lichvar

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From: "Eric Vyncke (evyncke)" <[email-masked]>
Date: Mon, 28 Jun 2021 14:53:58 +0000

Miroslav

Thank you for the quick reply. Please see in-line for EV>

NB: all my comments are non blocking

Regards

-éric

-----Original Message-----
From: Miroslav Lichvar <[email-masked]>
Date: Monday, 28 June 2021 at 16:12
To: Eric Vyncke <[email-masked]>
Cc: The IESG <[email-masked]>, "[email-masked]" <[email-masked]>, "[email-masked]" <[email-masked]>, "[email-masked]" <[email-masked]>, "[email-masked]" <[email-masked]>
Subject: Re: Éric Vyncke's No Objection on draft-ietf-ntp-interleaved-modes-05: (with COMMENT)

    Thanks for the review.

EV> this is also what I remember when  read the I-D several weeks ago. But, I still think that "are allowed" is perhaps too light.

EV> I agree with the cure (and its minor effect) but then why not adding this text in the I-D ?

    -- 
    Miroslav Lichvar