Traffic Control Algorithms for Integrated-Services Packet-Switched Networks

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In this research, we explore traffic control algorithms for integrated- services networks. which are networks that carry diverse traffic types such as computer data, voice, video, text, and images. ln such a network performance objectives and packet arrival processes vary tremendously from one data stream to another. Either networks must be designed with so much capacity that every conceivable set of performance objectives will be met, or algorithms are needed that differentiate packets and packet streams based on these characteristics and adjust delay distributions, loss probabilities, and blocking probabilities accordingly. We plan to develop an integrated set of traffic control algorithms based in part on a novel mechanism called the priority token bank. An admission control algorithm admits or blocks entire packet streams, where admitting a packet stream means guaranteeing its performance objectives will be met. In each queue, a scheduling algorithm orders the transmission of queued packets and a dropping algorithm selects packets to be discarded when buffer overflow occurs. Both algorithms effectively adjust delay distributions and loss probabilities to optimize performance at a given load as perceived by the applications, or, equivalently, to achieve a given level of performance at a higher load. We also explore usage-based charges for network services based on the packet arrival processes of admitted packet streams and on the corresponding performance achieved (and possibly guaranteed). These charges reflect the extent to which network resources are consumed. Policing and monitoring are also addressed. Algorithms are evaluated through analysis and extensive simulation by comparing delays, loss probabilities, blocking probabilities, and other relevant metrics, with those achieved with known algorithms.