Data communications and networking (sie) by behrouz forouzan is a comprehensive reference book for students pursuing their courses on networking. With detailed accounts on the data transmission protocols and networking, the book is a useful for various the engineering courses in communication, computer science, and it. Further, the book also finds usage as a preparatory material for the various other technology related courses too.this book starts with a detailed account on network models, thus providing the user with an ideal introduction on data transmission. The protocols and standards, as well as the physical structures of the networks are also discussed extensively here. The data communications and networking (sie) follows a descriptive pattern, thus engaging users of all kind.a number of diagrams and tabular representations are also included in the book, thus making it more useful for the reader. The much discussed osi model is also explained extensively with special emphasis on its layered architecture. Further, there are also chapters on bandwidth utilisation with multiplexing and spreading.to aid the electronic and communication students, the author has specifically included sections on switching, that emphasise on virtual circuit networks as well as circuit-switched networks. Also covered are topics such as wired lans, wireless lans, connecting lans, virtual lans, and multiple access.sections on congestion control, traffic management, and the methods to improve the quality of service can help to provide the reader a practical approach. Published in 2006 by McGraw-hill education, the fourth edition of this book comes in paperback. Key features: the contents are so arranged to ensure that it fulfills both the academic and research needs of the students.