Stallings, William <br/><br/>
Data and computer communications 

 - 7th ed. 
 - New Delhi  Pearson Education  2004 
 - xvi, 847 p. 
<br/><br/> Includes appendices, bibliographical references and index 
<br/><br/><label>ISBN: </label>81-297-0206-1 
<br/><br/><label>Dewey Class. No.: </label>S/C-S/T D65,4:(D65,8(B)) P4;2