I propose that the transmission of the stream of broadcasting from the server to the client can participate and the client itself, that is, from the servers Twitch will transmit to the client and if the speed of the Internet client (participant of the broadcast) allows, he will transmit to one or more other clients (the same broadcast) that will reduce the number of servers for one broadcast with a large online. Technically it is possible to do this only those who use the Twitch application. Of course, this action will slightly increase the delay of the broadcast, but this delay is not significant and will not greatly affect the experience of watching the broadcast. (The client is the streamer's viewers who use the Twitch app on different devices TV, Phone, Tablet)

.....................servers Twitch
..................../........................ \
............Client......................Client

........... / ......\ ..................... / ........\
.......Client......Client........Client.....Client
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........Client...... Client