Data signal is a light of frequency or that of electricity, which represents data as they go through a network or a computer channel or through a wireless network. Data signals are the electrical signals that are used to carry information in terms of data. Data from the computer are converted to electrical signals. On the other hand, voice signals are the electrical signals that are used to transfer voice from one point to another. A typical voice signal has a bandwidth of approximately 3 kHz. A video signal is a signal that transmits pictures and graphics from one point to another. Normal video signals operate at six megahertz (6 MHz)[ CITATION Sta07 \l 1033 ].
The three signals have for a long time been transmitted individually. With the development in data communication technologies, it is now possible to integrate the three signals in one transmission. There are technologies, which have been developed which integrate the three signals in one transmission. There are technologies, which are used to transmit these signals[ CITATION Fit08 \l 1033 ].
Voice over Internet Protocol VoIP) is a modern telephony system, which uses packet-switching technology, for example, the Internet to transfer digitized voice data from one point to another. This technology and capability allows companies that deal with communication to squeeze more conversation into the same bandwidth. It enables even home users to use computer software and VoIP handsets to make calls to other people who are online.
On the other hand, PBX (Public Branch Exchange) is a mash up of telephone networks that provides connections to a company and which allows calls to be made in and out the company. This technology is utilized by many companies because they are cheap. Instead of having individual lines for each department, the use of PBX technology and still get connections for each office[ CITATION Sta07 \l 1033 ].
FitzGerald, J., & Dennis, A. (2008). Business data communications and networking. London: John Wiley and Sons.
Stallings, W. (2007). Data and computer communications. London: Prentice Hall.