Voice quality in converging telephony and IP networks
The emergence of VoP technologies complicates the issue of voice quality. A user's perception of quality depends on three factors that share a complex relationship and have their own unique testing methods: clarity, end-to-end delay, and echo.
Stefan Pracht and Dennis Hardman, Agilent Technologies
As the telephone industry changes—specifically, as new technologies and services arise, as the industry applies technologies in different ways, and as new players become involved—maintaining the basic quality of a telephone call becomes increasingly complex. Although voice quality has evolved over the years to be consistently high and predictable, it is now an important differentiating factor for new VoP (voice-over-packet) networks and equipment. Consequently, measuring voice quality in a relatively inexpensive, reliable, and objective way becomes very important. Voice quality means different things depending on your perspective. On the one hand, voice quality is a way to describe and evaluate speech fidelity, intelligibility, and the characteristics of the analog voice signal itself. On the other hand, voice quality can describe the performance of the underlying transport mechanisms. Snip<>
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