Network integrated system and network integration method

摘要

PROBLEM TO BE SOLVED: To perform network integration having high fault tolerance.SOLUTION: In order to integrate a plurality of networks, each including a terminal, a relay unit having a gateway function and a bridge function, and an address allocation unit which allocates an address included in the set of allocated layer 3 addresses to the terminal, and each belonging to different layer 2 broadcast domains, an L2 tunnel which transfers data using a layer 2 address is configured between relay units. Then, the gateway function of a relay unit provided in one network is validated, and the bridge function of a relay unit provided in another network is validated. By the set of a layer 3 address range, a set of the layer 3 addresses included in the set range is allocated in a manner not to be overlapped among the networks.SELECTED DRAWING: Figure 1