PURPOSE: To improve the response to a caller even if there is a queue for a call processing by sending a call setting reception message to an outgoing line based on a call setting message when the call setting message from the input line is received.
CONSTITUTION: After a call setting message is sent, the internal path is set immediately. That is, an idle B channel is sought from a communication line in an exchange main body at the outgoing processing and secured. After securing the B channel, the outgoing processing connects an incoming idle B channel and an outgoing idle B channel to set an internal path. On the other hand, when the call setting reception message from the network side is received for the outgoing processing, the message reaches the incoming processing, in the process of message transmission, no setting of the internal path is executed. Thus, the impartial chance in securing the outgoing line to the caller is guaranteed.
FUKUSHIMA MASAFUMI
KOBAYASHI HIROSHI
AIDA KAZUO
NIPPON TELEGRAPH & TELEPHONE