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Re: [AVTCORE] Leap seconds

Kevin Gross <kevin.gross@avanw.com> Fri, 23 September 2011 15:46 UTC

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Date: Fri, 23 Sep 2011 09:48:24 -0600
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From: Kevin Gross <kevin.gross@avanw.com>
To: Qin Wu <bill.wu@huawei.com>
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Subject: Re: [AVTCORE] Leap seconds
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Qin,

Thank you for this reminder. I have revisited the IDMS draft and am reminded
that it does define a means to specify wallclock source. I think it could
use a little work but it is an excellent start.

The IDMS draft doesn't mention leap seconds but since it is a draft, that
can easily be changed!

I will contact Ray Brandenburg and see if I can offer to help with this.

I think it would still be useful to add some leap second discussion to 3550
but I would propose to work it out under IDMS first since IDMS receivers is
where these NTP timestamps will be most relied upon.

Kevin Gross


On Thu, Sep 22, 2011 at 3:52 AM, Qin Wu <bill.wu@huawei.com> wrote:

> **
> Hi, Kevin:
> Regarding how to know where the leap seconds are, I think, you may follow
> two potential ways:
> 1. you may take take David's suggestion, compare the NTP/RTP pairs in the
> two consecutive SRs to know if exception happen.
> 2. you may look at IDMS draft, the parameter clock source is  defined in
> SDP to signal the source for clock
>    synchronization. Using this parameter, the receiver may know where the
> leap seconds are.
> Does this make sense?
>
> Regards!
> -Qin
>
>

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