| 摘要 |
<p>PURPOSE:To control a call without depending upon a procedure of CCITT recommendation Nos. X20, X21, etc., by transmitting and receiving the call connection information based on the internal information of a text on a basic transmission control procedure, and proceeding a calling mode in a contention state. CONSTITUTION:When a computer terminal 2 has communication with a data terminal 1, a calling packet CR is transmitted to an interface device 3 as an incoming call packet CN via a network 4. Then an acknowledging answer ACK1 is sent back to a selecting sequence ENQ from the terminal 1, and therefore an incoming call display PAD service signal ICOM is produced from the packet CN received previously from the network 4. On the other hand, if an acknowledging answer ACK2 is sent back from the terminal 1, the device 3 transmits an incoming call acceptance packet CA to the network 4 and at the same time an end sequence EOT to the terminal 1 to have a contention state on a basic transmission control procedure.</p> |
