Facility (line and local) loopbacksEquipment protection (1:1) with redundant modulesMonitors DS3s for LCV, AIS, LOS, and LOFAutomatic in-service timerHot-swap capabilityCentrally managed by the system controller moduleMultiplexes/demultiplexes the VT1.5s in three STS-1s between the Optical Multiplexer (OMM) Module(s) and the DS1s of three DS3 facilities