Patent ID: 7761547

Claim:
A network system including a plurality of clients, an application server, a plurality of sensors each associated with a respective user of a plurality of users, at least one base station that terminates wireless communications from said plurality of sensors, and a sensor net server which includes a control processing processor, wherein: said sensor net server has a storage device that stores a first association between each of said plurality of sensors and a corresponding base station of said at least one base station and a second association between each of said at least one base station and a corresponding group of a plurality of groups; said control processing processor performs setting of a third association between each of said users and a corresponding group of said plurality of groups according to said first and second associations; and said application server contains a control unit that controls applications based on said plurality of groups; wherein: said application server comprises a communication interface unit, a control processing processor, and a data storage device; said control processing processor further performs processing of obtaining information on said groups from said sensor net server, and communicating with said sensor net server; and said data storage device stores a group management table that manages said group information; wherein: said application server sends a member list request for a specified group to said sensor net server during application control; said sensor net server that received said request sends a member list including the users in said specified group to said application server; said application server that received said member list establishes a communication session with a user included in said member list; wherein: said sensor net server sends a member list updating to said application server; and said application server that received said member list updating updates said group management table based on said member list updating, and establishes a communication session with a user that is included in said specified group in said group management table at the time of establishing the session.