Accession Number : ADA309947

Title :   Real-Time Communication for Distributed Computing.

Descriptive Note : Final technical rept. Oct 92-Jan 96,

Corporate Author : NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF COMPUTER SCIENCE

Personal Author(s) : Reeves, Douglas S.

PDF Url : ADA309947

Report Date : 23 MAY 1996

Pagination or Media Count : 22

Abstract : The subject of this research project was real time communication in switched networks (the Internet, and ATM). Distributed applications that have real-time requirements include voice and video transmission, real-time simulation, data acquisition, and distributed command and control. Real-time communication protocols should be practical to implement, easy to use, adaptable, and make efficient use of network resources. Previous research on hard and soft real-time communication was summarized and unified. A method which combines the best features of statistical multiplexing and deterministic delivery was then proposed. This method achieves high utilization and provides strong end to end quality of service (QoS) guarantees. A method of dynamic resource allocation was proposed and evaluated. This method uses less resources, is significantly easier to use, and provides equally good QoS, compared with the best static methods. Routing algorithms for uni- and multi-casting of real-time data were also investigated. The limitations of previous algorithms were shown, and improvements were suggested. A simulator for multicast routing experimentation was developed and made available to other researchers. Statistical modelling of variable bit-rate, compressed video traffic was investigated. Such models are useful for network performance evaluation and management. A method was proposed for shaping and smoothing of VBR video traffic at the user-network interface.

Descriptors :   *DISTRIBUTED DATA PROCESSING, *COMPUTER COMMUNICATIONS, *REAL TIME, *COMMUNICATIONS NETWORKS, *COMMUNICATION SWITCHING CENTERS, COMPRESSION, MATHEMATICAL MODELS, ALGORITHMS, COMPUTERIZED SIMULATION, REQUIREMENTS, DELIVERY, HIGH RATE, PERFORMANCE TESTS, TRAFFIC, DYNAMICS, STATISTICS, EFFICIENCY, TRANSMITTANCE, QUALITY, COMMAND AND CONTROL SYSTEMS, DATA ACQUISITION, ALLOCATIONS, RESOURCES, COMMUNICATION AND RADIO SYSTEMS, ROUTING, RESOURCE MANAGEMENT, STATISTICAL ANALYSIS, MULTIPLEXING, VIDEO SIGNALS, STATICS, UTILIZATION, DETERMINANTS(MATHEMATICS).

Subject Categories : Computer Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE