[94127] in North American Network Operators' Group
Re: Network end users to pull down 2 gigabytes a day, continuously?
daemon@ATHENA.MIT.EDU (Marshall Eubanks)
Wed Jan 10 05:57:24 2007
In-Reply-To: <Pine.LNX.4.64.0701101138050.29447@uplift.swm.pp.se>
Cc: nanog@merit.edu
From: Marshall Eubanks <tme@multicasttech.com>
Date: Wed, 10 Jan 2007 05:56:27 -0500
To: Mikael Abrahamsson <swmike@swm.pp.se>
Errors-To: owner-nanog@merit.edu
On Jan 10, 2007, at 5:42 AM, Mikael Abrahamsson wrote:
>
> On Tue, 9 Jan 2007, Valdis.Kletnieks@vt.edu wrote:
>
>> between handling 30K unicast streams, and 30K multicast streams
>> that each have only one or at most 2-3 viewers?
>
> My opinion on the downside of video multicast is that if you want
> it realtime your SLA figures on acceptable packet loss goes down
> from fractions of a percent into the thousands of a percent, at
> least with current implementations of video.
>
Actually, this is true with unicast as well.
This can (I think) largely be handled by a fairly moderate amount of
Forward Error Correction.
Regards
Marshall
> Imagine internet multicast and having customers complain about bad
> video quality and trying to chase down that last 1/100000 packet
> loss that makes peoples video pixelate every 20-30 minutes, and the
> video stream doesn't even originate in your network?
>
> For multicast video to be easier to implement we need more robust
> video codecs that can handle jitter and packet loss that are
> currently present in networks and handled acceptably by TCP for
> unicast.
>
> --
> Mikael Abrahamsson email: swmike@swm.pp.se
