War Dialing

A piece of hardware used to connect computers (or certain other network devices) together via a serial cable (usually a telephone line). When data is sent from your computer, the modem takes the digital data and converts it to an analog signal (the modulator portion). When you receive data into your computer via modem, the modem takes the analog signal and converts it to a digital signal that your computer will understand (the demodulator portion).
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A piece of equipment that joins a digital phone line to a piece of communication equipment, which may be a phone or a PC. Such equipment allows testing, condition, timing, interfacing, etc. However, it does not do what a modem does: namely, convert digital signals from machines into analog signals which can be carried on analog phone lines. The term “digital modem” is thus somewhat of a misnomer.
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A small version of the phone company’s central switching office. Also known as a private automatic branch exchange. A central telecommunications switching station that an organization uses for its own purposes. A sophisticated telephone system often used by organizations to provide inbound call support, extension-to-extension calling, conference calling, and voicemail. This can be implemented as a stand-alone phone system network or integrated with the IT infrastructure.
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A device connected to several other devices. In ARCnet, a hub is used to connect several computers together. In a messagehandling service, a hub is used for transfer of messages across the network. An Ethernet hub is basically a “collapsed networkinabox” with a number of ports for the connected devices. A network device used to connect multiple systems together in a star topology. Hubs repeat inbound traffic over all outbound ports.
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A device that uses a TV cable to deliver an Internet connection.
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