SUPERHIGHWAY
The SUPERHIGHWAY® family of products provides an effective way to combine legacy multiplexed trunk groups with an Ethernet LAN for transmission over a fiber optic or radio link. The product family has two main variants. A SUPERHIGHWAY LAN Combiner unit, which is designed to combine a single trunk group with a 10/100Base T LAN to provide a data overlay for existing area communications systems. The second application of this product is to provide the IP to serial conversion for a voice over IP network. In this application the unit provides the interface between a router or switch and the radio. The second main variant provides a group multiplexing capability to combine up to four multiplexed trunk groups, up to four orderwire channels and an Ethernet LAN for transmission over a down the hill radio or over up to 2 km of fiber optic cable
  
SUPERHIGHWAY® LAN Combiner(MTD-16100 and MTD-16200)
The function of the SUPERHIGHWAY® LAN Combiner is to convert the Ethernet LAN into a serial bit stream that can be combined with a trunk group from the existing switch system for transmission over a high capacity radio. The SUPERHIGHWAY® products can optionally be provided with bulk encryption to secure the traffic being transmitted.
SUPERHIGHWAY® Group Combiner(MTD-16000)
The group combiner version (also known as the TD 5079/U) is used to pass multiple trunk groups, a digital orderwire and an Ethernet LAN over a short distance between two communications shelters using fiber optic cable or over longer distances using LOS radio.