1. An electronic signal interlocking that controls a plurality of signals, comprising: a plurality of signal control devices, each of which includes a communication module, a processor module with a computer-readable medium encoded with a computer program, and an interface module to interface the device to a wayside signal unit that includes a signal head, an automatic train stop and a train detection apparatus, a data communication network to interconnect said signal control devices, a computer program segment at each signal control device that provides at least one of monitoring the operational state of said wayside signal unit, and controlling the operation of said wayside signal unit.