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Re: [xrblock] Comments on draft-ietf-xrblock-rtcp-xr-synchronization-00

Colin Perkins <csp@csperkins.org> Wed, 24 October 2012 14:44 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Wed, 24 Oct 2012 15:43:57 +0100
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To: Huangyihong <rachel.huang@huawei.com>
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Subject: Re: [xrblock] Comments on draft-ietf-xrblock-rtcp-xr-synchronization-00
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On 18 Oct 2012, at 04:30, Huangyihong (Rachel) wrote:
> Hi folks,
>  
> I have 2 comments for draft-ietf-xrblock-rtcp-xr-synchronization:
>  
> 1.       In RTP flows synchronization offset metric block, only one SSRC set to the SSRC of the reference RTP stream has been specified. IMO,  the SSRC of the reporting stream should be also required.
> 2.       Synchronization offset is a 64-bit unsigned fixed-point number. No indication shows which stream, the reporting stream or the reference stream,  is lag behind. So I propose to split one bit from “Reserved” field to indicate the offset direction.

It would probably be easier to implement if you made the Synchronisation Offset a signed 64 bit value, rather than an unsigned 64 bit value and a separate sign bit.

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

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