This book introduces the reader to the principles used in the construction of a large range of modern data communication protocols. The approach we take is rather a formal one, primarily based on descriptions of protocols in the notation of CSP. This not only enables us to describe protocols in a concise manner, but also to reason about many of their interesting properties and formally to prove certain aspects of their correctness with respect to appropriate speci?cations. Only after considering the main principles do we go on to consider actual protocols where these principles are exploited. This is a completely new edition of a book which was ?rst published in 1994, where the main focus of many international efforts to develop data communication systems was on OSI – Open Systems Interconnection – the standardised archit- ture for communication systems developed within the International Organisation for Standardization, ISO. In the intervening 13 years, many of the speci?c protocols - veloped as part of the OSI initiative have fallen into disuse. However, the terms and concepts introduced in the OSI Reference Model are still essential for a systematic and consistent analysis of data communication systems, and OSI terms are therefore used throughout. There are three signi?cant changes in this second edition of the book which p- ticularly re?ect recent developments in computer networks and distributed systems.

Communication protocols form the operational basis of computer networks and telecommunication systems. They are behavior conventions that describe how communication systems interact with each other, defining the temporal order of the interactions and the formats of the data units exchanged – essentially they determine the efficiency and reliability of computer networks. Protocol Engineering is an important discipline covering the design, validation, and implementation of communication protocols. Part I of this book is devoted to the fundamentals of communication protocols, describing their working principles and implicitly also those of computer networks. The author introduces the concepts of service, protocol, layer, and layered architecture, and introduces the main elements required in the description of protocols using a model language. He then presents the most important protocol functions. Part II deals with the description of communication protocols, offering an overview of the various formal methods, the essence of Protocol Engineering. The author introduces the fundamental description methods, such as finite state machines, Petri nets, process calculi, and temporal logics, that are in part used as semantic models for formal description techniques. He then introduces one representative technique for each of the main description approaches, among others SDL and LOTOS, and surveys the use of UML for describing protocols. Part III covers the protocol life cycle and the most important development stages, presenting the reader with approaches for systematic protocol design, with various verification methods, with the main implementation techniques, and with strategies for their testing, in particular with conformance and interoperability tests, and the test description language TTCN. The author uses the simple data transfer example protocol XDT (eXample Data Transfer) throughout the book as a reference protocol to exemplify the various description techniques and to demonstrate important validation and implementation approaches. The book is an introduction to communication protocols and their development for undergraduate and graduate students of computer science and communication technology, and it is also a suitable reference for engineers and programmers. Most chapters contain exercises, and the author's accompanying website provides further online material including a complete formal description of the XDT protocol and an animated simulation visualizing its behavior.

Original textbook (c) October 31, 2011 by Olivier Bonaventure, is licensed under a Creative Commons Attribution (CC BY) license made possible by funding from The Saylor Foundation's Open Textbook Challenge in order to be incorporated into Saylor's collection of open courses available at: http: //www.saylor.org. Free PDF 282 pages at https: //www.textbookequity.org/bonaventure-computer-networking-principles-protocols-and-practice/ This open textbook aims to fill the gap between the open-source implementations and the open-source network specifications by providing a detailed but pedagogical description of the key principles that guide the operation of the Internet. 1 Preface 2 Introduction 3 The application Layer 4 The transport layer 5 The network layer 6 The datalink layer and the Local Area Networks 7 Glossary 8 Bibliography

The authors introduce this new approach to programming language design, describe its evolution and design principles, and present a formal specification of a metaobject protocol for CLOS. The CLOS metaobject protocol is an elegant, high-performance extension to the CommonLisp Object System. The authors, who developed the metaobject protocol and who were among the group that developed CLOS, introduce this new approach to programming language design, describe its evolution and design principles, and present a formal specification of a metaobject protocol for CLOS. Kiczales, des Rivières, and Bobrow show that the "art of metaobject protocol design" lies in creating a synthetic combination of object-oriented and reflective techniques that can be applied under existing software engineering considerations to yield a new approach to programming language design that meets a broad set of design criteria. One of the major benefits of including the metaobject protocol in programming languages is that it allows users to adjust the language to better suit their needs. Metaobject protocols also disprove the adage that adding more flexibility to a programming language reduces its performance. In presenting the principles of metaobject protocols, the authors work with actual code for a simplified implementation of CLOS and its metaobject protocol, providing an opportunity for the reader to gain hands-on experience with the design process. They also include a number of exercises that address important concerns and open issues. Gregor Kiczales and Jim des Rivières, are Members of the Research Staff, and Daniel Bobrow is a Research Fellow, in the System Sciences Laboratory at Xerox Palo Alto Research Center.

"Cryptographic Protocol: Security Analysis Based on Trusted Freshness" mainly discusses how to analyze and design cryptographic protocols based on the idea of system engineering and that of the trusted freshness component. A novel freshness principle based on the trusted freshness component is presented; this principle is the basis for an efficient and easy method for analyzing the security of cryptographic protocols. The reasoning results of the new approach, when compared with the security conditions, can either establish the correctness of a cryptographic protocol when the protocol is in fact correct, or identify the absence of the security properties, which leads the structure to construct attacks directly. Furthermore, based on the freshness principle, a belief multiset formalism is presented. This formalism’s efficiency, rigorousness, and the possibility of its automation are also presented. The book is intended for researchers, engineers, and graduate students in the fields of communication, computer science and cryptography, and will be especially useful for engineers who need to analyze cryptographic protocols in the real world. Dr. Ling Dong is a senior engineer in the network construction and information security field. Dr. Kefei Chen is a Professor at the Department of Computer Science and Engineering, Shanghai Jiao Tong University.

This thesis is on the subject of network protocol design. It takes a collection of known, practical problems that we face on the Internet—namely, abuses of the network—and considers these problems in light of both existing practical countermeasures and abstract analysis. Protocol design features and techniques with Machiavellian robustness are then proposed to address these problems, to the extent that such a remedy is possible. A protocol called ‘Invite’ is then designed from scratch using these new techniques. The Invite protocol thus serves as a practical example of design for Machiavellian robustness, but its duty as a protocol is to convey that robustness to some other protocol, so it is then applied to email (and its well-known abuses such as spamming and mailbombing). In that context, its effectiveness is analysed and compared with other approaches, both proposed and currently practised. Lastly, the broader implications of Machiavellian robustness are considered, suggesting possible avenues of future research.