Patent ID: 8140700
Filing Date: 2012-03-20
Classification: H04L

Abstract:
1. In a parent computer system that is network connectable to one or more child computer systems, a method for inviting a child computer system of the one or more child computer systems to join a multi-cast session of a multi-cast root computer system, the method comprising: accessing, by the parent computer system, a designated multi-cast address for the multi-cast session; sending, by the parent computer system to the child computer system at the designated multi-cast address, a multi-cast invite message configured to invite the child computer system to join the multi-cast session, wherein the multi-cast invite message includes a session identifier that includes information comprising the designated multi-cast address, a network address of the multi-cast root computer system, and a designated multi-cast port, and wherein the child computer system is configured for receiving the sent multi-cast invite message and for joining the multi-cast session based on the information in the received multi-cast invite message, and for receiving a multi-cast packet of the multi-cast session at the designated multi-cast address in response to the joining, and for checking a source address of the received multi-cast packet of the multi-cast session, and for sending a multi-cast status message to the parent computer system in response to the source address matching the network address of the multi-cast root computer system, and for discarding the received multi-cast packet of the multi-cast session in response to the source address not matching the network address of the multi-cast root computer system; receiving, by the parent computer system from the child computer system in response to the sent multi-cast invite message, the multi-cast status message indicating that the child computer system joined the multi-cast session based on the information in the sent multi-cast invite message and then received from the root computer system at least one multi-cast packet for the multi-cast session, wherein the root computer system is distinct from the parent computer system; and sending, by the parent computer system to the child computer system in response to the received multi-cast status message, a message that includes a next multi-cast sequence number associated with a next multi-cast packet of the multi-cast session, the message separate from the next multi-cast packet of the multi-cast session; wherein the multi-cast root computer system sends the next multi-cast packet of the multi-cast session to the one or more child computer systems including the child computer system, and wherein the sent next multi-cast packet of the multi-cast session includes the next multi-cast sequence number and the network address of the multi-cast root computer system, and wherein the multi-cast session includes the parent computer system, the child computer system, and the multi-cast root computer system that sends conference data of the multi-cast session in multi-cast packets, including the next multi-cast packet, that are receivable by the one or more child computer systems.