00538    a2200205   4500020001800000082001500018100002300033245003100056250000900087260004500096300002300141650003000164650001700194650001900211650002100230700002300251700001800274700001800292700002200310  a9788131722893  a004.6bVOI  aDavidson, Jonathan  aVoice over IP fundamentals  a2nd.  aNew DelhibPearson educationc2008g2008  axxiv, 394p.c24cm.  aGateway central protocols  aPSTN service  aVoice security  aSignaling system  aMukherjee, Sudipto  aPeters, James  aBhatia, Manoj  aKalidindi, Satish