Patent ID: 7269728
Filing Date: 2007-09-11
Classification: H04L

Abstract:
1. A method of distributing a single video conference to at least three member devices via a multicast data group and a multicast session, the method comprising the steps of: establishing a plurality of virtual channels for the video conference multicast session, each virtual channel simultaneously carrying multiple streams of video conference data of the single video conference, each stream transmitted from a different member device, each virtual channel defined by an amount of time remaining until expiration, at least two of which are different, and being operable to deliver the same video conference to member devices associated with that respective virtual channel; receiving, at a key distributor device, a request from a requester device to join the multicast session, the request device indicating a requested start time for joining the video conference and an amount of time of utilization of the multicast session; selecting a virtual channel from the plurality of virtual channels for communications by the requestor by correlating the start time and the amount of time indicated by the requestor with the amount of time remaining until expiration of the virtual channels at that start time; forwarding a new key for the selected virtual channel to the requester; forwarding the new virtual channel key to all pre-existing members of the selected virtual channel; distributing the video conference data signal to the members of the multicast group via each of the virtual channels, whereby the requestor device joins the video conference multicast data group without prompting re-keying of other member devices of the video conference associated with virtual channels other than the selected virtual channel.