A Made IT project http://www.made-it.com info@made-it.com

DS-0 is the unit that describes the way one analog voice channel is converted into a digital signal.

To convert an analog voice to channel to a digital signal you need to sample the analog signal according to the PCM standard. The sampling rate was set to 8000 samples per second and they decided to use 8 bits per channel for encoding. This way every channel needs 8000 x 8 = 64000 bits per second (64 kbps).