Since HD is defined as 720p (yes there are debates about that) the CONTENT MATTERS since low motion, stereo content could be quite slow at well under 1 megabit per second.
Also, since there is buffering going on, during slow motion scenes the buffer can fill and a lower bandwidth will still get the job done.
Then means there is no exact requirement given all the variables and the answer must be "HD streaming network speed needs what it needs."
Bob
What network speed and/or bandwidth needed for HD streaming?

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