Patent ID: 6477149
Filing Date: 2002-11-05
Classification: H04L,H04W

Abstract:
A network system in which a plurality of networks are connected to each other through a repeater, said plurality of networks include mobile hosts capable of moving while conducting communication between said plurality of networks, fixed hosts that do not move, and mobile host supporting nodes for supporting communication with said mobile hosts, said mobile host supporting nodes are defined in said mobile hosts, respectively, said mobile hosts, when conducting multicast communication, participate in a multicast group in a form of conducting multicast communication directly from a network out of said plurality of networks in which said mobile hosts currently exist and in a form of conducting multicast communication through said nodes for supporting communication with said mobile hosts, said repeater transmits a group inquiry message for inquiring a multicast group in which said mobile hosts, said fixed hosts and said mobile host supporting nodes in said networks connected to said repeater participate, and said mobile hosts, said fixed hosts and said mobile host supporting nodes transmit a group report message in response to said inquiry message, said mobile hosts comprising:a) direct participation multicast group managing means for managing a multicast group in which said mobile hosts participate in a form of conducting multicast communication directly from a network out of said plurality of networks in which said mobile hosts themselves currently exist; b) indirect participation multicast group managing means for managing a multicast group in which said mobile hosts participate in a form of conducting multicast communication through said nodes for supporting communication with said mobile hosts themselves; and c) control means for transmitting a group report message constructed of only multicast groups managed by said direct participation multicast group managing means when receiving said group inquiry message.