The Application of Digital Broadcast Communication to Large Scale Information Systems

A new type of information system is described that combines personal computers, broadcast data communication, and bidirectional communication. The system is designed to use broadcast communication whenever possible to deliver information to personal computers, which are used for data storage, indexing, and retrieval. This paper starts with an overview of the system, and then discuss the problem of reliable digital broadcast communication in some detail. A parameterized broadcast protocol is described, and we show how to choose protocol parameters based on observed channel error characteristics. A flexible encryption-based protection system is included in the protocol. We discuss the implementation of the system on contemporary personal computers. A broadcast system based on these ideas is now operating in Boston area homes.