MOBILE COMMUNICATION SYSTEM AND A SHORTEST PATH COMMUNICATION METHOD, PARTICULARLY FOR PERFORMING SHORTEST PATH COMMUNICATION BETWEEN A MOBILE NODE HAVING A MOBILE-IPV6 AND THE OPPOSITE HALT NODE NOT HAVING THE MOBILE-IPV6

摘要

PURPOSE: A mobile communication system and a shortest path communication method are provided to enable a mobile node having a mobile IPv6 to directly communicate with the opposite halt node which does not have the mobile IPv6 without transforming a router of a network where the opposite halt node belongs to. CONSTITUTION: Mobile-IPv6 networks(links)(1,2) are directly connected to the Internet(I), and an IPv6 network(3) and an IPv5 network(5) are connected to the Internet(I) via a gateway(5). The mobile-IPv6 network(1) includes an HA(Home Agent)(11), a router(12) connected to the Internet(I) and a mobile node(13). The mobile node(13) is assigned a home address as a permanent address. When the mobile node(13) is connected to the network(2) called an external network, away from the network(1), a COA(Care-Of-Address) for indicating a current position of the mobile node(13) is assigned. The mobile-IPv6 network(2) includes a router(22) connected to an HA(21) and the internet(I). The IPv6 network(3) includes a router(31) connected to the gateway(5) and the opposite halt node(32). The IPv4 network(4) includes a router(41) connected to the gateway(5) and the opposite halt node(42). A position management module(51) stores position-related information between HA and COA of each mobile node. An IP address conversion module(52) converts an IP address between the IPV6 and IPv4.