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

"Huangyihong (Rachel)" <rachel.huang@huawei.com> Thu, 18 October 2012 03:31 UTC

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From: "Huangyihong (Rachel)" <rachel.huang@huawei.com>
To: "xrblock@ietf.org" <xrblock@ietf.org>
Thread-Topic: [xrblock] Comments on draft-ietf-xrblock-rtcp-xr-synchronization-00
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Date: Thu, 18 Oct 2012 03:30:54 +0000
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Subject: [xrblock] Comments on draft-ietf-xrblock-rtcp-xr-synchronization-00
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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.

Best Regards!