Re: [Ntp] comments on draft-mlichvar-ntp-ntpv5-03 / Message Format

Dan Drown <dan-ntp@drown.org> Thu, 25 November 2021 04:38 UTC

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Date: Wed, 24 Nov 2021 22:38:10 -0600
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From: Dan Drown <dan-ntp@drown.org>
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Subject: Re: [Ntp] comments on draft-mlichvar-ntp-ntpv5-03 / Message Format
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This email will be on the "4. Message Format" section.

Right now the flags/era/timescale fields come before root dispersion  
and root distance. This puts them at a different offset in the packet  
compared to their location in NTPv4. Was there a reason not to keep  
these at the same offset? It's not an implementation problem, just a  
cosmetic difference.

For timescale offset, there is an overlap with the unknown value  
(0x8000/-1.0 seconds) during a negative leap second smear. Is this  
worth mentioning in the rfc?

Transmit Timestamp currently has: "In responses it is the time when a  
response to the client was transmitted. The specific response depends  
on the selected mode (basic or interleaved). The timestamp corresponds  
to the beginning of the transmission"

I'm suggesting this rewording: "In responses it is the beginning of  
the transmission of a response to the client. Which response it refers  
to depends on the selected mode (basic or interleaved). See  
Measurement Modes section below for detail."