Patent ID: 6088141
Filing Date: 2000-07-11
Classification: H04J,H04L,H04Q

Abstract:
A Communication node for communication with other nodes by receiving optical energy on incoming optical links and transmitting optical energy on outgoing optical links, which node comprises:first incoming link supervision means for detecting incoming optical energy from a first incoming optical link;second incoming link supervision means for detecting incoming optical energy from a second incoming optical link;optical switching means for switching incoming optical energy from the first or the second optical incoming link to the first or second optical outgoing link;control means connected to the supervision means and switching means for controlling whether the node is in a normal mode, a head mode or a tail mode of operation in response to the detection of incoming optical energy on one or both of the incoming optical links; andrecovery means for testing to determine if it is possible to recover from the head or tail mode to the normal mode.