Methods, systems, and devices are described for managing virtual network services provided to a network by a self-contained network services system. Consequently, the connection member according to the present invention has the effect of effectively interconnecting the electrode terminals of the battery cells through a simple assembly process. When the first IP telephone terminal goes into an on-hook state, an IP telephone exchange which manages the first IP telephone terminal switches the call connection between the first and second IP telephone terminals to a call connection between the holding device and the second IP telephone terminal.