Re: [Ntp] The NTP WG has placed draft-roughtime-aanchal in state "Call For Adoption By WG Issued"

Miroslav Lichvar <mlichvar@redhat.com> Wed, 11 September 2019 15:01 UTC

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Date: Wed, 11 Sep 2019 17:01:15 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: ntp@ietf.org
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Subject: Re: [Ntp] The NTP WG has placed draft-roughtime-aanchal in state "Call For Adoption By WG Issued"
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On Wed, Sep 11, 2019 at 07:42:38AM -0700, Watson Ladd wrote:
> On Wed, Sep 11, 2019 at 12:06 AM Miroslav Lichvar <mlichvar@redhat.com> wrote:
> > If I understand it correctly, Roughtime could be specified as an NTP
> > extension field, possibly as an extension to NTS. So, I think the
> > document should explain why a new protocol using a different transport
> > was needed. I guess one reason could be that Roughtime is easier to
> > implement than NTP, especially in some specific frameworks.
> 
> The signing negatively affects the possible timing accuracy

I think with the interleaved mode that wouldn't have to be the case,
but even if it was, why would it matter? It wouldn't be worse than
what is currently specified, right?

> and you
> need to track things differently on the server.

Meaning it would be more difficult to add the support to an NTP server
than implement it as a separate service?

> What are the benefits from adding it as an extension?

The "proof of malfeasance" could cover the timestamps that the client
is using to synchronize the clock. I'm not sure if there is any value
in that.

-- 
Miroslav Lichvar