| 摘要 |
<p>This apparatus includes exterior gateways (C1,..., C72) for linking with the outside world, switching modules (M1,..., M9) provided with switching gateways (A1,..., A6, B1,..., B6) linked to the exterior gateways by way of a connection network. A certain number of connecting gateways (B1 to B6 from M1, M2, M4, M5, M7, M8) of the modules is allocated to backup and a connection network is prebuilt for linking these backup gateways to the exterior gateways to be repaired. <IMAGE></p> |
