Abstract: A wireless base station device connected to a network and communicating with an external device includes: a control management unit to store operation information in a database and manage the operation information, and the control management unit includes an operation information read portion to read operation information from the database, supplied from the external device; a determination portion to determine whether or not the operation information is beyond a period of validity, read from the database along with the operation information that corresponds to the request; a operation information update portion to read the operation information that corresponds to the request from corresponding units when the operation information that corresponds to the request is beyond the period of validity, and updating the database; and a response transmission portion to transmit the operation information to the external device.

Abstract: A group communications switching method is disclosed. The method includes the steps of: maintaining a voice call between a first subscriber terminal and a second subscriber terminal when it becomes necessary to perform group communications while the voice call is in progress; starting a group communications call by the first subscriber terminal so as to call at least a group communications member other than the first subscriber terminal and the second subscriber terminal; and disconnecting the voice call between the first subscriber terminal and the second subscriber terminal when the group communications call is established.

Abstract: A group communications switching method is disclosed. The method includes the steps of: maintaining a voice call between a first subscriber terminal and a second subscriber terminal when it becomes necessary to perform group communications while the voice call is in progress; starting a group communications call by the first subscriber terminal so as to call at least a group communications member other than the first subscriber terminal and the second subscriber terminal; and disconnecting the voice call between the first subscriber terminal and the second subscriber terminal when the group communications call is established.

Abstract: In a disaster system control method and apparatus transmitting disaster status information through a mobile communication network or a fixed communication network, in order to promptly transmit/receive disaster status information at a time of a disaster occurrence between a disaster monitoring person and afflicted people within a disaster occurrence area, a bandwidth control apparatus assigns a bandwidth for a packet call in preference to other calls, a mobile terminal installs an application for disaster thereon for transmitting/receiving disaster status information between a disaster system center and the mobile terminal itself, and the disaster system center provides the mobile terminal within a disaster occurrence area with an application for disaster startup mail to start up the application for disaster.