Patent ID: 7336631

Claim:
A radio network system of a radio network including a plurality of Radio Bearer Servers (hereafter “RBSs”) which controls transfer of data communicated between a communication terminal and a radio base station, and at least one Radio Control Server (hereafter “RCS”) which controls the plurality of RBSs, wherein each of the plurality of RBSs notifies the RCS of a resource using state indicating a using state of a resource which controls the transfer of the data, and the RCS holds resource using states notified by the plurality of RBSs, receives a call, selects one RBS from the plurality of RBSs based on the resource using states, and assigns the call to a selected RBS, wherein each of the plurality of RBSs sets up a threshold value for judging whether to notify the resource using state, and notifies the RCS of the resource using state when the resource using state exceeds the threshold value.