Held, Gilbert  1943- <br/><br/>
Understanding data communications / 
Gilbert Held 
 - 7th ed. 
 - Boston, Mass :  Addison-Wesley,  2002 
 - 765 p. :  ill. 
<br/><br/>Includes bibliographical references and index 
<br/><br/><label>ISBN: </label>0672322161 
<br/><br/><label>Subjects--Topical Terms: </label><br/>DATA TRANSMISSION SYSTEMS<br/>COMPUTER NETWORKS
<br/><br/><label>LC Class. No.: </label>TK5105  / H442U 2002