Data, Voice, and Video Signals

Data, Voice, and Video Signals

Charles Williams

IT/242

October 27, 2011

Philippe Rowland

Data, Voice, and Video Signals

Signaling is used to represent data, voice, and video on a network. Signaling is also the method for using radio waves, light energy, or electrical waves to communicate (Regan, 2004, p. 75). Changing a signal to represent data is a process called encoding or modulation. Digital and analog are two forms of signaling. The signals used to transmit data, and the data can be in digital or analog form. Data, voice, and video are types of network traffic.

Data is electronic information found in images, files, digitally encoded voice and video, documents, and databases. Data networks are usually cell switched or packet switched to ensure the recovery and error control needed to complete a reliable transfer of data. Voice is produced by vibrations of compressed air (Regan, 2004, p. 84). On a digital carrier, an analog voice signal needs to be converted to a digital signal. Video traffic is like data and voice traffic, requiring reliable end-to-end transport and sharing the same requirements as voice traffic. Private branch exchanges (PBE’s) and Voice over IP (VoIP) are different in many ways.

A private branch exchange is a telephone system located in an enterprise that switches calls between enterprise users on local lines, but allowing all users to share some external phone lines. Phones connected to a PBX have an extension number which enables intra-switch phone calls, eliminating a need for an external phone line. PBX’s also can be connected to other PBX’s via dedicated trunk lines. A PBX includes multiple phone lines that terminate at the PBX, a computer managing the switching of calls in and out of the PBX, a network of lines within the PBX, and a switchboard for an operator. Voice over IP (VoIP) is voice delivered using the Internet protocol (Regan, 2004, p. 566). This means voice is sent in packets rather than circuit-committed...