Patent ID: 6661972
Filing Date: 2003-12-09
Classification: H04B,H04J

Abstract:
A node for use in an optical communication network, comprising:a first input configured to receive an input from a first optical fiber transmitting signals in a first direction; a second input configured to receive an input from a second optical fiber transmitting signals in a second direction opposite to the first direction; a first output configured to output signals to the first optical fiber in the first direction; a second output configured to output signals to the second optical fiber in the second direction; first and second transmitters configured to generate signals at different respective first and second frequencies; first and second receivers configured to receive signals at the different respective first and second frequencies; a first optical switch connected between said first and second transmitters and said first and second outputs, and configured to output signals from either one of said first and second transmitters to either one of said first and second outputs; and a second optical switch connected between said first and second inputs and said first and first receivers, and configured to provide signals from either one of said first and second inputs to either one of said first and second receivers.