VoIP Service Quality, Measuring. Evaluating 2

Book Title:	VoIP Service Quality: Measuring & Evaluating Packet-Switched Voice
Author:	William C. Hardy
Publication:	McGraw-Hill Professional Jan 2003
ISBN:	0071410767

Book Review: Voice Over IP Service,Book Review: VoIP Service Quality, Measuring & Evaluating

The evolution of the Internet, coupled with that of computers everywhere has brought along changes that reach into previously stagnant areas. The old fashioned telephone system had seen few revisions since the discovery that digital signals travel further and are less prone to noise, and now a new technology is opening up the way for some interesting possibilities.

Called Voice over IP or VoIP for short, this new idea means to digitize analog voice signals, embed them into regular IP packets and transmit them over the existing Internet infrastructure. The advantages of this are easily seen: low cost for intercontinental calls, the ability to exchange multimedia files as well as communicate through voice at the same time and so on. However, the way the Internet works right now is not, by default, optimized for VoIP. Data packets have little or no control over the way they are routed or the order in which they arrive at the destination and if VoIP communication is to work, it must be a real-time process, and this is usually achieved by compression, using some sort of Real-Time Transport Protocol and managing the QoS (Quality of Service) issues.

QoS is all about the cost and quality tradeoffs that must be considered when deploying VoIP systems, and can include tricks and policies that manage the voice packet flow in the routers they cross, like packet queuing methods, Congestion Avoidance, special fields in the IP protocol to describe the type of service and so on.

VoIP Service Quality : Measuring and Evaluating Packet-Switched Voice deals with the various Quality of Service issues and ways to translate those into measurable factors that can be more easily evaluated.
VoIP might be attractive if the cost and flexibility of the telephone service is considered, but companies need the guarantee of quality if the new technology is to be adopted, and this book has solid information about measuring and increasing the Quality of Service.

VoIP Service Quality has three main parts. The first is about the basics, dealing with topics such as connection quality, the different expectations customers have for voice quality and the application of these to packet-switched networks. The second part is about the objective ways to measure and analyze voice quality and its implications on the design and management of the solution, once it is deployed. It outlines automated test systems, with a comparative description of each. The third section looks ahead to the measurement of the quality of the services that the author proposes as viable for the future, comprising of both data and voice.

The book shows what to look for in assessing VoIP quality and how various packet-switched solutions can affect this quality, enhancing or negating a caller’s experience, as well as describing tests for examining call set-up times, determining requirements for multimedia exchange and how to apply various effects to the initial voice data.

VoIP Service Quality is helpful in understanding what the transition from regular phone lines to voice over IP means for companies in terms of objectively assessing the quality their employees and customers will no doubt estimate on their own, so the transition to VoIP is for the best.

Book Review 1