Gregory, Peter, <br/><br/>
SIP Communications for Dummies / 
Peter Gregory 
 - 64 pages ;  22 cm. 
<br/><br/>Includes bibliographical references and index 
<br/><br/><label>ISBN: </label>0470041498 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Internet telephony