*The #1 VoIP bestseller for technical professionals (now completely updated! *All-new chapters on gateways, call processing, and traffic engineering *IP and the PSTN: advanced interoperability solutions *TRIP: the breakthrough protocol for voice message delivery *Cisco Voice QoS: traffic prioritization, congestion control, signaling, policies, and more The authoritative guide to Internet voice communications (now completely updated! Voice Over IP, Second Edition is the essential guide for telecommunications professionals who must understand or deploy VoIP. Leading network consultant Uyless Black carefully evaluates VoIP's challenges and compelling advantages, and then reviews every technical standard and platform. This thoroughly updated Second Edition reflects dramatic improvements in VoIP standards and practice, adding completely new chapters on gateways, RSVP and DiffServ call processing, and traffic engineering. *Reviews key technical obstacles to successful VoIP deployment, including packet loss and variable delay *Covers emerging approaches to interoperability between IP networks and the public switched telephone network *Introduces Telephony Routing Over IP (TRIP), the breakthrough protocol for voice message delivery *Covers Cisco Voice QoS network optimization in detail: traffic prioritization, congestion control, signaling, QoS management, and policy control *Shows how to establish paths to service providers through the local loop via ISDN, xDSL, and HFC *Contains concise, to-the-point introductions to H.322, Megaco, MGCP, and SIP Voice Over IP, Second Edition is everything you need to know about running voice over IP networks today(from technical fundamentals to next-generation protocols and beyond.