Summary
This chapter explored analog signaling technologies, such as loop-start, ground-start, and various E&M signaling approaches. Additionally, this chapter described digital signaling approaches, including CAS (channel associated signaling) and CCS (common channel signaling).
Conversion between analog and digital waveforms involves the process of sampling the original voice wave and converting that sample into a binary value. The Nyquist Theorem specifies the number of samples per second to take from an analog waveform. Specifically, the Nyquist Theorem states that samples should be taken at a rate that equals twice the highest frequency being sampled. For example, if the highest frequency being sampled is 4000 Hz (as it is in the VoIP world), ...
Get Authorized Self-Study Guide Cisco Voice over IP (CVoice) now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
