In-service optical performance monitoring of high-speed transparent networks based on Q measurements

The all optical network (AON) of the future envisages the ability to transport a mix of voice, data and video signals over optical channels, regardless of bit rate and transmission format. The main obstacles to fulfilling this are limitations in the functions of performance monitoring and network management. At present, system bit error rate (BER) measurements, histograms and Q factor measurements on the electrical layer are used to assess the performance of digital data links. These tests require information about the bit rate and protocol, and are either very slow (BER) or very costly. The solution proposed here uses Q factor analysis as a method of non-bit-rate-dependent in-service performance monitoring to get around the disadvantages mentioned above.