The core technology used in a videoconferencing system is digital compression of audio and video streams in real time. The hardware or software that performs compression is called a codec (coder/decoder). Compression rates of up to 1:500 can be achieved. The resulting digital stream of 1s and 0s is subdivided into labeled packets, which are then transmitted through a digital network of some kind (usually ISDN or IP). The use of audio modems in the transmission line allow for the use of POTS, or the Plain Old Telephone System, in some low-speed applications, such as videotelephony, because they convert the digital pulses to/from analog waves in the audio spectrum range. COUNT 5
QSN1 What is the software that performs audio and/or video compression? ANS1 a codec (coder/decoder) QSN2 How high can compression rates go? ANS2 1:500 QSN3 What is one digital network through which a digital stream can be transmitted? ANS3 IP QSN4 What does POTS stand for? ANS4 Plain Old Telephone System QSN5 What do POTS do? ANS5 convert the digital pulses to/from analog waves