Re: [AVTCORE] Working Group Last Call on draft-ietf-avtcore-leap-second-03

Colin Perkins <csp@csperkins.org> Mon, 26 August 2013 12:57 UTC

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From: Colin Perkins <csp@csperkins.org>
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Subject: Re: [AVTCORE] Working Group Last Call on draft-ietf-avtcore-leap-second-03
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On 15 Aug 2013, at 08:46, Magnus Westerlund <magnus.westerlund@ericsson.com> wrote:
> This starts the WG last call on RTP and Leap Seconds with the intended
> status of Proposed Standard. Please provide any comments by 1st of
> September.
> 
> https://datatracker.ietf.org/doc/draft-ietf-avtcore-leap-second


Section 5 says that: "No special treatment with respect to RTP timestamps is required in the presence of a negative leap second". This might be clearer written "No special treatment is needed to avoid ambiguity with respect to RTP timestamps in the presence of a negative leap second". I think some special treatment is needed, as noted in Section 5.2, to avoid jumps in the playout time. 

Section 5 also says NTP includes leap seconds, and that implementations working to a leap-second-bearing reference need "a working communications channel to receive notification of leap-second scheduling". Is having an NTP-synchronised clock a sufficient channel to receive the necessary notification, or is something more needed? 

Typos:
- Section 3, 1st paragraph: "synchronized with with the rotation"
- Section 6, 2nd paragraph: "leap-seocnd-bearing"


Cheers,
Colin



-- 
Colin Perkins
http://csperkins.org/