| 摘要 |
<p>PURPOSE: To prevent communication cells from being left by using safety information (P) annexed to route information (W) to be evaluated as a key on a connection stage when the P annexed to the W is inverted and recognized as an error at the time of moving the W to the end of a W block, and only at the time of recognizing no error, transmitting a communication cell. CONSTITUTION: Each communication cell to be transmitted by the ATM switching device VE having multi-folded connection stages (KSs) 1, 2 is received and transmitted. Thereby a W block having plural W data corresponding to the number of connection stages KS to be passed in the device VE is arranged on the head of each communication cell. Each W evaluated by one of the KSs is continued to the transmission of each communication cell and transferred to the route of the W block in each W and individual safety information (P) is annexed to each W in the W block. When the annexed P is inverted and recognized as an error due to the movement of the W to the end of the W block, a communication cell is transmitted only at the time of recognizing no error by using the P annexed to the W as a key by the KS. Consequently communication cells are prevented from being left.</p> |
