"Ma Bell" (the Bell Telephone System and American Telephone & Telegraph, and others) spent years and billions of dollars creating, perfecting and maintaining a telecommunications network dedicated to providing the most reliable voice communication service in the world. The Internet was created as a closed communication network.Īlmost all communications networks have as their basis the same set of Telephony (Telepho–Ny) standards and practices.
Ethernet, for example was created to facilitate data communication within a closed system that was contained within an office building. Some communication transmission protocols were developed to work independently of the Telephone System. The modem's transmission medium is typically copper wire, fiber, or radio. However, look at a schematic of its components, and you will see elements labeled as "XMTR" and "RCVR". The transmitter and receiver elements of a data modem (such as the type used in a traffic signal system controller box) may not be readily visible. The mouth (and vocal cords) is the transmitter, ears are the receivers, and air is the transmission medium over which sound travels between mouth and ear. Every human being is equipped with a basic communication system. Transmitter, receiver, transmission medium – these are the basic elements that make up a communication system.
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