Ransome, James F., <br/><br/>
Voip Security 
James F. Ramsome, John W. Rittinghouse. 
 - U.K :  Digital Press,  c2005. 
 - xxi,402 p.:  ill.; 
<br/><br/><label>ISBN: </label>8131203018 
<br/><br/><label>Dewey Class. No.: </label>004.62  / RAN/VOI