| 摘要 |
<p>A network device monitors a signal transmitted to and received from a wireless or optical link for detecting a bit-by-bit coincidence between them. In response to the detection of the coincidence, the network device determines that the received signal is a copy of the transmitted signal. The network device further monitors its transition states for detecting a predetermined state which persists indefinitely during a link failure. When the predetermined state and a copy of the transmitted signal are simultaneously detected, the network device discontinues its predetermined state and enters a normal state. <IMAGE></p> |
