Patent ID: 7391767

Claim:
A method of providing IP (Internet Protocol) multicast service using a VLAN (Virtual Local Area Network) in a network including an IP multicast/VLAN manager for supporting an IGMP (Internet Group Management Protocol) and a GVRP (GARP VLAN Registration Protocol), and multicast group members, said method comprising the steps of: a) after generating an IP multicast group, allowing a sender to request the IP multicast/VLAN manager to search for at least one host joining the IP multicast group, the step a) comprising the steps of: a1) allowing the sender to request the IP multicast/VLAN manager to manage registration or withdrawal of a host in and from the generated IP multicast group; a2) allowing the sender to give notice of a multicast session through an SDP (Session Description Protocol) if the IP multicast/VLAN manager accepts the request; and a3) allowing the IP multicast/VLAN manager to register or withdraw the host in and from the IP multicast group if the host requests the IP multicast/VLAN manager to register or withdraw the host in and from the IP multicast group; b) allowing the IP multicast/VLAN manager to check though a router directly coupled to the host whether the host supports the VLAN; and c) allowing the sender to transfer a packet through the VLAN if the host joining the IP multicast group supports the VLAN and allowing the sender to broadcast a packet through IP multicast if the host joining the IP multicast group does not support the VLAN; wherein the SDP has a new field so that the IP multicast group can use the VLAN.