
Are packets duplicated in live video broadcast? - tomthehero
If 10 users are being served a live video broadcast stream of 1mbps bitrate by a server, does the server require 10mbps bandwidth or is 1mbps enough?<p>Since the server is serving exactly same data to multiple clients, does it send multiple copies of same packets with different destination addresses or does it send a single copy of a packet with a list of destination addresses?<p>If the commonly used protocols doesn&#x27;t support this, are there any not so widely used options?
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detaro
You can't send a packet with a list of destination addresses.

There is multicast, where clients can register "I'd like a copy of all packets
to $address please", but it doesn't work on public internet. It's used by some
providers for TV streaming inside their networks though.

There's also peer-to-peer approaches, where clients share the data they
receive with other clients, similar to Bittorrent.

The most common approach is individual streams from the servers to the clients
though.

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tomthehero
Does youtube use multicast?

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detaro
No. As I said, multicast generally doesn't work across networks you don't
control (and also needs special clients, can't be used with browsers).

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bradknowles
What you could do is send your stream from your source machine to a streaming
server, and then have the streaming server send that out to the clients.

This is how live-streaming on YouTube or twitch.tv works.

