Hersent, Olivier IP telephony : deploying voice-over IP protocols / Olivier Hersent, Jean-Pierre Petit and David Gurle - Chichester : John Wiley, c2005. - xxxiii, 382 p. ; ill. ; 25 cm. ISBN: 0470023597 LCCN: Subjects--Topical Terms: Internet telephony LC Class. No.: TK5105.8865 / .H47 2005 Dewey Class. No.: 621.38212 / H571i