Patent ID: 7822004
Filing Date: 2010-10-26
Classification: H04W

Abstract:
1. A system for establishing a data transmission line between mobile telephone terminals, comprising: a plurality of radio base transceiver stations accommodated in a mobile telephone network through an identical IP (Internet Protocol) network; and a call agent device provided to the IP network, wherein: the call agent device comprises: the system establishes a data communication line between the radio base transceiver station on the calling side and the radio base transceiver station on the called side through the call agent device, in a case where the called terminal is subordinated to the radio base transceiver station on the called side itself, the data communication line being established for transmitting data to be exchanged between the calling terminal and the called terminal, the data communication line connecting the radio base transceiver station on the calling side and the radio base transceiver station on the called side to each other through the IP network without routing through the mobile telephone network.