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CUT6 6.2
Computers: Understanding Tech 6e 6.2
| Term | Definition |
|---|---|
| communications medium | A connection that enables computers in different locations to send data to one another. |
| twisted-pair cable | A cable that consists of pairs of copper wires, in which each wire is individually wrapped in plastic and all the wires are bound together by another plastic casing. |
| electromagnetic interference (EMI) | The magnetic field generated when electricity passes through a wire. |
| shielded twisted-pair (STP) cable | A type of twisted-pair cable used in environments where electromagnetic interference (EMI) might be a problem, such as for a cable that passes over a fluorescent light fixture in a ceiling. |
| unshielded twisted-pair (UTP) cable | A type of twisted-pair cable that does not have magnetic shielding on the outside. UTP cable is available in different categories, such as Cat5 (meaning “category 5”). |
| coaxial cable | A type of cable that consists of an insulated copper center wire grounded by a shield of braided wire; commonly used for cable TV connections, in telephone networks, and in some computer networks. |
| fiber-optic cable | A type of cable that uses a string of glass to transmit data using patterns of photons (beams of light). |
| network backbone | The central pathway of a network. |
| T line | Any of several types of digital high-speed, long-distance telephone lines that are capable of carrying multiple types of signals, including both voice and data. |
| T1 line | A T line that carries data at 1.5 Mbps over its 24 internal lines, with each line running at 64 Kbps. |
| T3 line | A T line that contains a bundle of 672 individual lines. Working collectively, these lines can transfer data at up to 43 Mbps. |
| wireless media | Wireless technologies that transmit information through the air. |
| Wi-Fi | The wireless form of Ethernet. |
| IEEE 802.11 | The IEEE standard number for wireless Ethernet (Wi-Fi). IEEE stands for Institute of Electrical and Electronics Engineers—the organization that maintains the standards for various types of computer and communication technologies. |
| band | A frequency range. |
| wireless access point | A hardware device that communicates wirelessly with Wi-Fi capable devices. |
| infrastructure mode | A communication mode in which a Wi-Fi device connects to a wireless access point. |
| ad hoc mode | A communication mode in which two computers connect to one another via Wi-Fi directly without an access point. |
| WiMAX | A wireless technology that has a larger usable range than Wi-Fi, is based on the IEEE 802.16 standard, and is suitable for blanketing a small metropolitan area with wireless coverage. |
| Bluetooth | A short-range wireless networking standard used to connect peripheral devices to computers, tablets, and smartphones. |
| cellular technology | A wireless communication technology that uses antenna that cover areas of 10 to 12 square miles to provide mobile phone service and Internet service. |
| cell | In networking and communication: A wireless cellular calling area, which has its own antenna encompassing an area approximately 10 to 12 square miles in diameter. |
| 3G | Acronym for 3rd generation. A class of mobile broadband service that provides about 3 Mbps throughput. |
| 4G | Acronym for 4th generation. A class of mobile broadband service that is capable of around 9.5 Mbps throughput. |
| communications satellite | A solar-powered electronic device positioned in the Earth’s outer atmosphere in geosynchronous orbit, containing several transponders. |
| transponder | A transmitter and receiver that receives signals from a transmission station on the ground called an earth station and rebroadcasts them to a different earth station. |
| earth station | A transmission station on the ground that sends signals to satellite transponders. |
| geosynchronous orbit | An orbit around the Earth that has the same movement as the Earth itself, making objects in this orbit appear stationary when viewed from the ground. |
| latency | A delay involved in communication that limits the performance of the communication medium. |
| microwave system | A high-frequency waveform radio signal used to carry data securely from one point to another. |
| infrared technology | A wireless technology that transmits data as light waves, rather than radio waves. |
| IrDA | The standard for infrared wireless communication. IrDA is short for Infrared Data Association, the organization that developed the standard. |