| 摘要 |
<p>PURPOSE: To evade a waste of network resources when the congestion occurs by disusing selectively the cells to be relayed through an exchange based on the message structure of a higher order and excluding positively the cells which are insignificant to a receiving terminal. CONSTITUTION: A cell disuse control circuit 300 extracts the connection identifier out of each cell received from a multiple circuit 201 and outputs a message type and a processing mode in response to each extracted connection identifier. This output is read out of a connection attribute table stored previously in the circuit 300, and a processing mode includes three types, i.e., the transfer, permutation and disuse modes. Based on the decision of these modes, the cells passed through the circuit 300 are stored in a common buffer 203 by a buffer control circuit 800 and the disused cells are sent to the circuit 300. When the next cell is processed and a message break point is detected, the processing mode is reset to the transfer mode so that a transfer operation is carried out as normal. Thus the cells which are insignificant to a receiving terminal are disused in a network, and the waste of the network resources can be evaded when the congestion occurs.</p> |
