摘要:In 2002 voice over IP will constitute more than 25% of all long distance voice calls, according to Network World. That's more than a 30% ramp-up from 2001. The emergence of SIP, MPLS and new quality of service tools is making carrier grade voice over IP a service reality, and a potentially huge margin booster and revenue driver for service providers. The first edition of Carrier Grade Voice over IP played a roll in VoIP growth, in less than year becoming an essential tool for carriers working to provide high quality IP telephony. This new edition vastly updates the SIP chapter, details MPLS, and takes the explanations of the previous edition a step further in a final chapter that shows, step by step, how to design working VoIP networks.