US Patent 7881616 Transceiver based loop back initiation

An operational optical transceiver configured to initiate operation in loop back mode. The optical transceiver includes transmit and receive signal paths, a memory capable of having microcode written to it, and a configurable switch array that is used to connect and disconnect the two signal paths as appropriate for a desired loop back mode. The microcode is structured to cause the optical transceiver to control the configurable switch array. This allows for analysis and diagnostics of the signal data.