Re: [rtcweb] #27: Section 6.2 FEC

Magnus Westerlund <magnus.westerlund@ericsson.com> Mon, 26 August 2013 06:09 UTC

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Date: Mon, 26 Aug 2013 08:10:57 +0200
From: Magnus Westerlund <magnus.westerlund@ericsson.com>
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To: rtcweb issue tracker <trac+rtcweb@trac.tools.ietf.org>
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Subject: Re: [rtcweb] #27: Section 6.2 FEC
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On 2013-08-26 01:10, rtcweb issue tracker wrote:
> #27: Section 6.2 FEC
> 
>  There are several block-based FEC schemes that are designed for use
>     with RTP independent of the chosen RTP payload format.  At the time
>     of this writing there is no consensus on which, if any, of these FEC
>     schemes is appropriate for use in the WebRTC context.  Accordingly,
>     this memo makes no recommendation on the choice of block-based FEC
>     for WebRTC use.
> 
>  [BA] While I realize that it is not easy to decide on which FEC scheme is
>  appropriate for WebRTC, including a recommendation on retransmission but
>  not FEC is problematic.
> 

Bernard, this is the WG consensus that we so far have arrived on. If you
have a proposal regarding FEC, please make it and lets see if we can
reach consensus on such a proposal.

However, I fail to see how this is generally problematic. Retransmission
will cover certain parts of the deployment cases when the transport RTT
and delay does not prevent it from being able to repair in a timely
fashion. FEC clearly covers transport characteristics where
retransmission will show its shortcomings. If one want improved
transport performance in those cases clearly a common implemented FEC
solution is desired.

Cheers

Magnus Westerlund

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