Re: [Ntp] [ New Version Notification for draft-gruessing-ntp-ntpv5-requirements-02.txt]

Miroslav Lichvar <> Mon, 14 June 2021 11:04 UTC

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Date: Mon, 14 Jun 2021 13:04:09 +0200
From: Miroslav Lichvar <>
To: James <>
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Subject: Re: [Ntp] [ New Version Notification for draft-gruessing-ntp-ntpv5-requirements-02.txt]
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On Sat, May 22, 2021 at 06:31:13PM +0000, James wrote:
> URL:  
> Status:
> Htmlized:
> Diff: 

I'd like to see this draft considered for adoption. We need to agree
on the NTPv5 requirements before we can discuss the details of the
actual protocol.

I have few comments on some specific parts of the document:

- "The specification MUST have support for servers to notify clients
   that the service is unavailable, and clients MUST have clearly
   defined behaviours honouring this signalling."

  This looks like a good goal but I suspect we may not be able to
  define a useful behavior for an unauthenticated context.

- "Leap second smearing SHOULD NOT be part of the wire specification"

  I think the protocol needs to have some way to indicate that the
  server has leap smearing enabled. Servers implementing leap smear,
  but clients not knowing about it (e.g. using its own leap second
  source) is a major concern in some environments.

- "Encryption and authentication MUST be provided by the protocol
   specification as a default"

  It's not clear to me what the default means here. That it is enabled
  by default in all implementations that support it?

Miroslav Lichvar