openCU is made to close the gap between Multipoint Control Unit based expensive hardware solutions and proprietary, web-based subscription solutions like Adobe breeze (Macromedia Breeze) or Webex from Cisco.
openCU employs a conference control protocol that has proven to be quite robust and allows for the expression of detailed state regarding the relations of each conference participant to each other participant. In conjunction with a reflector software it allows for customized distribution of conference media, so that nothing is transmitted unless it is used. The protocol is limited in the size of the conference it can serve, but our[who?] investigations have shown that this can be extended. The video is encoded in an ad hoc format that was designed for a particular family of desktop machines that were widespread in the past. What it lacks in mathematical elegance, it makes up for in quickness. Comparison of Radvision Hardware MCU and CUSeeMe Networks Software MCU
The client software has "alpha" status and binary packages for Windows XP are available. The software is double licensed under the Agpl.
Update: In 2013 we decided, because of development and standarisation of Opus_(audio_format), WebM, Mumble_(software) and the change of licence in Qt_(framework) to completely redisign the client / server structure.