|
If you've got a wide area network (WAN) already, putting interoffice voice traffic on it is an obvious application for it. Voice signals take up so little bandwidth, and the cost savings can be so significant, that Voice over IP (VoIP) deserves serious consideration. However, you can easily throw away years of cost savings by bringing in consultants to implement your VoIP solution. Deploying Cisco Voice over IP Solutions is meant to help organizational information technology people (as well as engineers at service providers and, for that matter, the expensive consultants) learn how to design, implement, and fine-tune VoIP systems that center on equipment and software from Cisco Systems. This book is all about Quality of Service (QoS), capacity management (gatekeeping), and network design. Cisco's implementations of fax services (under T.37 and T.38) and unified messaging (under uOne) are covered as well, but the authors leave most call-control matters to this book's companion volume, Cisco CallManager Fundamentals: A Cisco AVVID Solution. The authors' approach, in large part, takes the form of a series of engineering problems, in which answers to design questions are given with lots of supporting math, equipment specifications, and references. In a discussion of setting up a transcontinental VoIP network, for example, the authors show how to configure Internetwork Operating System (IOS) 12.x to act as a gatekeeper and interact with CallManagers at both sites. There's IOS syntax, of course, but also a discussion of how Hot Standby Routing Protocol (HSRP) affects gatekeeping duties, and a complete table of options. A well-thought-out system for providing prepaid calling-card services on a VoIP network--meaning there's a database and authentication built into the call flow--is a great conclusion. --David Wall Topics covered: Design- and implementation-time considerations for building a Voice over IP (VoIP) network on Cisco Systems hardware and software. Traffic analysis, echo, Quality of Service (QoS), dial plans, and extended services like fax and messaging get the attention of the all-Cisco authorial team. |
