I'm interested in video conferencing and content sharing at the same time. How is the whole thing made? From what I've found in the internet I saw that the protocol that is used is H.239 over H.323, but basically that's all I found.
Are there several types of sharing content? Are the voice and video sharing the same stream with the content? Is the content available only on another screen or it can be mixed with the video in the same screen? Is there a place where can see a sample call flow of the whole operation?
There is several method for content share.
SIP: BFCP (open two video channels, one for main video and other for content video channel).
H.323: H.239 (open two video channels, one for main video and other for content video channel).
Also TIP for sending multiple video stream in same video channel.
BFCP/H.239 is common method for sending content channel.
It open two video channels and sending video stream separately but usually audio will mix (mix audio from microphone and other input like DVD audio a part of content sharing).
Basic call flow (in most common method) for H.239 is…,
Addition to above content sharing method, Cisco TelePresence MCU support content sharing on main video channel (MCU mix content video channel into one of video panel in main video stream) for Endpoint doesn’t support 2nd video capability.