| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently utilize a band, a VPI(virtual pass identifier), a VCI (virtual channel identifier) by a method for setting a VC(virtual channel) for a subscriber line signal in a line to connect an ATM exchange with an ATM line concentration device. SOLUTION: A VC for a subscriber line signal is set by informing a call preparation signal from a subscriber's terminal 3 to an ATM exchange 2 for every call by using a metasignaling. In this case, related to the ATM exchange 2, a VPI and a VCI is decided by retrieving empty VPI and VCI by a VPI/VCI empty and occupied state managing tables 21, 22 of the ATM exchange 2 and the ATM concentration device 1 of the VC for metasignaling signal, the VPI, the VCI and completion of setting them are informed to each other by using an M channel 5 for maintenance, the call preparation signal is set and released by using a C-plane 4 for transmitting and receiving the subscriber line signal, and communication is performed by using a U plane 7 for transferring user information.</p> |
