If you are using mpeg1 you can just dump the packets on the line. And if you want to get fancy you can read in a HQ stream and setup a beefy server to run 3 or 4 conversions to different bandwith classes and move clients up and down as required.

My code is geared to robots -- and has not been updated recently but there is at least a example of the simpler multiplexing in go.

https://github.com/mbrumlow/webbot