| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the occurrence of new fault such as processing delay and data abandonment and to surely perform restoration processing by confirming the state of all virtual channels VCs by one status investigation message (STATUS ENQUIRY). SOLUTION: When abnormality is caused between a terminal and an ATM switch (exchange) and it is restored within a fixed time, the status investigation message for confirming the state of all the virtual channels VCs capable of transmission and reception before abnormality occurrence is transmitted from signaling of both. Thereafter, at the time of receiving the status investigation message, the terminal and the ATM switch both transmit a status message in which the state of the corresponding virtual channel VC is set. Then, by the state included in the status message respectively transmitted from the terminal and the ATM switch, holding is performed in the cast that the virtual message VC is usable and disconnection is performed in the case that it is unusable.</p> |
