A Graph Model Analysis Of Computer Communications Protocols

The large scale computer networks being constructed demand that for effective utilization, protocols be established to regulate the communications between the attached computer systems. Assurance that these communications protocols are well behaved (e.g. do not deadlock) must be achieved. This report focuses on the analysis of computer-to-computer communications protocols using graph modeling techniques. Computer-to-computer communications protocols are examined and the issues of error control, flow control, multiplexing, and synchronization are identified and discussed. A sample protocol is developed. The UCLA Graph Model is explained and used to model and analyze the sample protocol. The ARPANET Initial Connection Protocol is also modeled and analyzed with significant results. The concept of a graph module is introduced. Graph modules are defined and used to simplify the model of the sample protocol. (Author).

This is a book about the bricks and mortar out of which are built those edifices that so well characterize late twentieth century industrial society networks of computers and terminals. Such computer networks are playing an increasing role in our daily lives, somewhat indirectly up to now as the hidden servants of banks, retail credit bureaus, airline reservation offices, and so forth, but soon they will become 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 work 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 finds himself in suddenly unfamiliar territory. It is no longer sufficient for him to think of transmission, modulation, noise immun ity, error bounds, and other abstractions of a single communication link; he is dealing now with a topologically complex interconnection of such links. And what is more striking, solving the problems of getting the signal from one point to another is just the beginning of the communication process. The communication must be in the right form to be routed properly, to be handled without congestion, and to be understood at the right points in the network. The communication scientist suddenly finds himself charged with responsibility for such things as code and format conversions, addressing, flow control, and other abstractions of a new and challenging kind.

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.

Analysis of Computer and Communication Networks provides the basic techniques for modeling and analyzing two of the fundamental components of high performance networks: switching equipment, and software employed at the end nodes and intermediate switches. The book also reviews the design options used to build efficient switching equipment. Topics covered include Markov chains and queuing analysis, traffic modeling, interconnection networks, and switch architectures and buffering strategies. This book covers the mathematical theory and techniques necessary for analyzing telecommunication systems. Queuing and Markov chain analyses are provided for many protocols currently in use. The book then discusses in detail applications of Markov chains and queuing analysis to model more than 15 communications protocols and hardware components.

The increasing number of computer networks has aroused users' interest in many and various fields of applications, in how a computer network can be built, and in how it may be used. The fundamental rules of computer networks are the protocols. "A protocol is a set of rules that governs the operation of functional units to achieve communication" [STA-86}. The book follows a practical approach to protocol speci fication and testing, but at the same time it introduces clearly and precisely the relevant theoretical fundamentals. The principal objectives of this work are: to familiarize readers with communication protocols, to present the main, formal description techniques, to apply various formal description techniques to protocol specification and testing. It is considered that the readership will primarily consist of protocol developers, protocol users, and all who utilize protocol testers. Secondly the book is suggested for postgraduate courses or other university courses dealing with communication networks and data communication. A large part of the book provides a comprehensive overview for managers; some parts are of especial interest to postal organizations. The book consists of three parts: the first part introduces the OS! Reference Model, it provides an overview of the most frequently used protocols and explains the fundamentals of protocol testing. The second part familiarizes readers with the methods used for protocol 5pecification, generation, and testing. Finite-state machines, formal grammars, Petri nets and some speCification languages (SDL, ESTELLE, LOTOS) are discussed in a pragmatic style. The third part deals with applications.

The main idea behind the series of volumes Advances in Petri Nets is to present to the general computer science community recent results which are the most representative and significant for the development of the area. Thepapers for the volumes are drawn mainly from the annual International Conferences on Applications and Theory of Petri Nets. Selected papers from the latest conference are independently refereed, and revised and extended as necessary. Some further papers submitted directly to the editor are included. Advances in Petri Nets 1991 covers the 11th International Conference on Applications and Theory of Petri Nets held in Paris, France in June 1991. The volume contains the Bibliography of Petri Nets 1990 prepared by H. Pl}nnecke and W. Reisig, with over 4000 entries.