Traffic management to enhance quality of service (QoS) of multimedia over available bit rate (ABR) service in asynchronous transfer mode (ATM) networks.

摘要

The Internet is growing exponentially and is impacting every aspect of modern life. Voice and video-based multimedia applications are expected to become a significant portion of the World Wide Web, but support for multimedia applications in the current Internet is still in its infancy. Though Internet Engineering Task Force (IETF) is developing technologies such as integrated services, differentiated services, and multiprotocol label switching, to meet the demands of multimedia applications; these technologies are still under development and not yet widely deployed.; Asynchronous Transfer Mode (ATM) is a high speed networking technology that provides seamless support for voice, video and data applications. ATM is being widely deployed in campuses and carrier backbones. To accommodate heterogeneity and to achieve efficiency we expect that future multimedia applications will be adaptive. We propose to use the ATM's ABR (available bit rate) service, since it has minimum rate guarantees and closed loop feedback control that minimizes cell loss.; We design and analyze traffic management methods to enhance the quality-of-service for multimedia applications over ABR service. Multimedia applications require that bandwidth, delay and loss are guaranteed in a certain range. We develop a rate allocation switch algorithm and a general form of fairness to enhance the bandwidth capability. We prove by simulation and analysis that the scheme developed converges to the fair allocation in various network topologies. We design three additional rate allocation schemes based on an overload factor. A comparison of these algorithm is given using simulation results and analysis. End-to-end delay has various components such as propagation delay, processing delay, and queuing delay. The varying component of delay is queuing delay. The queuing delay is reduced, by using an appropriate queue control function. We develop several queue control functions that can be used to dynamically control the queuing delay. Simulation and analysis is done to identify the best queue control function. We have built a software-based testbed to evaluate and demonstrate the various methods developed in this thesis.; Most of methods developed to solve the problems are general, and can be applied to design methods to support adaptable multimedia applications of the future Internet.