| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a line selection device by which an optimum line is selected not relying on the judgement of a network manager in an ATM transmission system. SOLUTION: When automatic virtual path conductivity characteristic test instruction information 43 is given to a control section 21 in a monitor controller, a virtual path conductivity test is started through a control section 35 of each ATM cross connect device 12. A test cell is set to have a lower priority than that of a user cell and a wider frequency band than a required frequency band, and the state of the line is grasped by observing an abort cell by the test cell. A line with the highest priority is selected depending on the test result, then the control section 21 sets a new path to a virtual path conversion section 34. Then the line is switched when the test cell is actually sent and the test is finished normally.</p> |
