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.
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.
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