The present subject matter relates to methods, circuitry and equipment providing a multi-functional, cost effective, media independent, open platform for communication services using differential signaling interfaces. The methods, circuitry and equipment comprise a plurality of input amplifiers, output amplifiers, and multiplexer switches or resistive dividers, which provide the ability to monitor, provide service protection switching, provide redundant services, provide on-demand service, provide service upgrades, security, test, and troubleshoot any communication devices and services.