Multimode Communications on the MITRENET
Abstract This paper presents a brief review of the MITRE local networking approach using CATV coaxial cable and describes some of our current networking activities. Multimode communications implies that many communications services are provided simultaneously on the same cable system. A wide-band distribution system is first shared using frequency division multiplexing techniques. Then individual FDM channels can be further shared using TDM techniques such as slotted Aloha, carrier-sense multiple access, or reservation techniques. A well developed technology exists for such a wide-band system using Community Antenna Television (CATV) components. This medium provides a bandwidth of 300 megahertz, constant receive signal strength, a high signal-no-noise ratio, good isolation, and reliable components and connection techniques. Currently MITRE is developing a variety of TDM techniques for use on coaxial cable, the design of public key crypto systems for application to local networks, integrated data and voice systems, the technical control of local networks and local network protocols.