monline

Streaming video to the iPhone became "standardized" with the release of iOS 3 (ie. iPhone 3) in the summer of 2009. There're a few key aspects of streaming video to the iPhone ...

• video must be encoded with H.264 Baseline profile without frame-reordering
• audio must be encoded with AAC (optionally HE-AAC)
• the video+audio streams must be packed into an MPEG-2 transport stream
• the transport stream must be split into small chunks (the app doing this is usually called a "stream segmenter"), these chunks are then saved (or uploaded) to a web server and served as usually (plain static files, nothing special about it, any webserver will do)
• a unicode encoded M3U file (aka. M3U8) is created on the webserver with a list of these chunks/segments
• the client downloads the M3U file and starts playing/downloading the individual pieces

In case of a live stream the M3U file is updated regularily and the client refreshes (redownloads) it regularily too.

A nice whitepaper on the subject is available from Akamai's iPhone site (you'll have to register though to download).

It has a nice table for suggested video bitrates for various resolutions and network bandwidths.
I've saved it in case they take down the wp:

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