In a wireless communication system, a utilization of a global ID having a long bit length, which is useful for linking with an external system, is compatible with a reduction of a communication amount of a wireless terminal. The wireless terminal transmits the global ID only when the wireless terminal is initially registered, and after a local ID having a short bit length is allocated by a server to the wireless terminal, this wireless terminal uses one the local ID. While the server manages a corresponding relationship between the global ID and the local ID, the server uses the global ID in order to identify the wireless terminal in a communication made outside the system.