Showing papers on "Throughput published in 1972"
01 Nov 1972
TL;DR: It is shown qualitatively that automatic-repeat-request (ARQ) systems are inherently better suited to the task than forward-error-control (FEC) systems.
Abstract: In this paper the nature of errors on telephone data communications channels and the basic techniques for dealing with these errors are discussed. Results of measurements recently taken on dialed connections are reviewed, and it is observed that conventional random-error- or burst-error-correcting codes cannot assure reliable communication on these channels. More generally, it is shown qualitatively that automatic-repeat-request (ARQ) systems are inherently better suited to the task than forward-error-control (FEC) systems. The throughput, or effective data rate, of ARQ systems is discussed, and two basic types of ARQ systems, stop-and-wait and continuous, are compared. It is concluded that with the more common stop-and-wait system, the throughput is unsatisfactory in applications involving high transmission rates and/or long propagation delays. A brief summary of error-correcting codes suitable for use on telephone channels (when a return channel is not available for ARQ) is included. Finally, hybrid schemes where FEC systems are embedded within ARQ systems are briefly discussed.
202 citations
15 Jun 1972
TL;DR: Research efforts to determine the most economical configurations to meet growth requirements in the ARPANET, properties of packet switched computer communication networks, analysis and design techniques for large scale networks, and cost/throughput/reliability characteristics of large packet switched networks for potential application to Defense Department computer communication requirements are described.
Abstract: : The document describes research efforts to determine: (1) the most economical configurations to meet growth requirements in the ARPANET, (2) properties of packet switched computer communication networks, (3) analysis and design techniques for large scale networks, (4) cost/throughput/reliability characteristics of large packet switched networks for potential application to Defense Department computer communication requirements The heart of the research program has been the dual attack on basic network theoretical problems and the development of computational techniques for handling large network structures Results on properties of the ARPANET, properties of large networks, and new computational techniques are described for subjects as traffic sensitivity, peak bandwidth, reliability, cost and throughput and routing
3 citations