A DSP is a specialized processor that has been in use for many years in other telephony applications such as mobile/wireless networks. They are attractive for internet telephony because they are small, use relatively little power, and are very fast. Packet voice requires computational-intensive operations and special processing, and a standard microprocessor is not up to the task of performing these operations.

In addition, packetized voice requires considerable multiplication and addition functions in a very short period of time. A DSP is designed to support these types of functions. Multiplication operations to estimate the frequency spectrum of a signal are very computationally intensive, and are often ...

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