Cheswick, William Retc <br/><br/>
Firewalls and internet security / 

 - 2nd ed. 
 -  Pearson Education ,  2003. 
 - p.xii+433 
<br/><br/><label>ISBN: </label>812970207X 
<br/><br/><label>Subjects--Index Terms: </label>Firewalls