Patent ID: 7194258

Claim:
A wireless communication network which is capable of handover comprising: a base station apparatus for communicating with a wireless terminal and a wired communication network; a control device having a handover unit for selecting one or plural signals from signals received from plural settable communication paths in accordance with a state of a transmission wave and communicating with the base station apparatus; and a network management device for managing a network, wherein the network management device: creates a base station group by selecting, in accordance with a predetermined rule, one or plural base station apparatuses in which software will be upgraded, and sends software for upgrading and an upgrading request to a base station apparatus belonging to the base station group; wherein the base station apparatus belonging to the base station group: receives the software and upgrading request sent from the network management device, changes the state of the transmission wave so as to switch a communication path in which communication services are being provided to another communication path through another base station apparatus by performing handover from the base station apparatus to another base station apparatus by the control device in accordance with the received upgrading request, upgrades software set therein to the received software, and returns the state of the transmission wave after software upgrading to its original state, and wherein the network management device further: has a memory for storing a number of call connections in the base station apparatus belonging to the base station group, an identifier of the base station group to which the base station apparatus belongs and/or an identifier indicating the base station apparatus does not belong to any base station group with respect to an apparatus identifier for identifying the base station apparatus, and selects the base station apparatus having the least call connections or a predetermined number of call connections or fewer from the base station apparatus not belonging to any base station group with reference to the memory and creates a base station group.