Pluggable transceiver module with enhanced circuitry

Pluggable transceiver modules with additional functions and circuitry contained within the module. In a first embodiment, additional circuitry is added to determine bit error rates at the point of the module itself. This allows a much better diagnostic evaluation of location of problem. In an alternate embodiment, various logic is placed in the module. In a first alternate embodiment encryption/decryption units are placed in the converter module so that encryption and decryption operations on the serial bitstream do not need to be performed in a switch. Existing switches can be used but the interconnecting links can still be encrypted. A second alternate embodiment includes compression/decompression units placed in the module to allow effective higher throughput on the selected links.