During the 1982/83 first year performance-period under this Grant, research investigations have been carried out leading to significant results, of both theoretical and practical importance. A large multitude of computer communication network architectures, models and control schemes have been developed, analyzed and evaluated. In particular, results have been obtained in the following areas: priority-based Time Division Multiple Access schemes; dynamic random-access procedures, with applications to local area networks and to local distribution and packet-radio networks; hybrid multiple-access schemes; polling, adaptive polling and probing access-control techniques; buffer capacity constrained multi-access systems; network topological analysis; local area network topological analysis; local area network protocols; integrated packet and circuit networks;integrated routing and flow control.

The remarkable advances in digital communication techniques have made computer networking and its performance evaluation very important and attractive when coping with the growing complexity of the information society. The scope of this book ranges from theoretical results in performance evaluation techniques, to their applications in computer networking (local and wide area networks), satellite communication, network architecture, parallel processing systems and database systems. The contributions to modelling and measurement methodologies, and the presentation of the state-of-the-art of performance evaluation techniques, will make this volume of interest to anyone concerned with these disciplines.

This is a book about the bricks and mortar from which are built those edifices that will permeate the emerging information society of the future-computer networks. For many years such computer networks have played an indirect role in our daily lives as the hidden servants of banks, airlines, and stores. Now they are becoming more visible as they enter our offices and homes and directly become part of our work, entertainment, and daily living. The study of how computer networks function is a combined study of communication theory and computer science, two disciplines appearing to have very little in common. The modern communication scientist wishing to work in this area soon finds that solving the traditional problems of transmission, modulation, noise immunity, and error bounds in getting the signal from one point to another is just the beginning of the challenge. The communication must be in the right form to be routed properly, to be handled without congestion, and to be understood at various points in the network. As for the computer scientist, he finds that his discipline has also changed. The fraction of computers that belong to networks is increasing all the time. And for a typical single computer, the fraction of its execution load, storage occupancy, and system management problems that are in volved with being part of a network is also growing.

Document studies the broad area of flow control and sequencing in computer communication networks. A special use of message sequencing is shown to reduce to a Markov process. A more general sequencing model is also studies; only approximate results are obtained in this case. The author formally shows that an end-to-end flow control scheme in computer communication networks can be modeled as a closed network of queues. He also introduces and analyzes a flow control scheme based on limiting the permit generation rates. It turns out that this scheme is very effective. More importantly, this scheme involves essentially no computational complexity. This allows us to measure and adjust the network performance with little difficulty. The simplicity also allows us to incorporate more realistic aspects of network protocols such as piggy-back acknowledgement, time-out and gate functions into our analysis. Two simple but effective distributed dynamic flow control schemes are proposed and analyzed. It is shown that with either of these two schemes, a network can respond well to the dynamically changing environment.