EST 320 Test Material – Quiz Answers >Test Complete Updated Spring 22/23.

Quiz 1  Digital signaling: is used by TDM.  The Open Systems Interconnection (OSI) reference model: is a de jure standard.  The voice band developed by the telephone company is the range of frequencies from: 300 Hz to 3,400 Hz.  Ethernet: was released as a de facto standard in 1980.  In the earliest stages of telephone use, to call one telephone from another required the two telephones to be directly connected by a pair of wires carrying electricity. True  Glass fibers can carry very large numbers of calls simultaneously. True  The biggest advantage of public packet data networks (PDNs) was cost; it was generally far less expensive to send computer data over a PDN than over the regular telephone network. True  Using a technique called wavelength division multiplexing (WDM), one strand of optical fiber can carry as many as 129,024 conversations at the same time. True  Computers do not possess voices. Their exchanges involve transmitting the bits (0s and 1s) that represent computer data. Because of this, the name data communications was adopted to distinguish it from voice communications between people. True  FDM is the same technique that allows multiple radio and television stations to transmit their programs simultaneously over the same medium (air), yet allow an individual radio or television set to tune into a particular broadcast apart from all the others. True Quiz 2  Fiber optic cables: cannot be bent at extreme angles  What is used to measure the distance that a wave travels in one cycle? Wavelength  Historically speaking, what was the first type of fiber optic cable to be produced? Multimode  What material in a fiber optic cable covers the cladding and absorbs light rays that escape the core and are moving out through the cladding? Coating  Which EMR frequency band is utilized by most television remotes? Infrared  Currently, the most commonly used guided electrical medium in network communications systems is twisted pair. True  Signals progress along a medium by a process called propagation. True  Because thermal noise can be eliminated, it is not a major factor in electrical signal transmission, and does not limit the distance that a signal can travel before it attenuates too much to be distinguished from the noise. False  The distance a wave travels in one cycle is its wavelength. True  Thermal noise cannot be eliminated by shielding the cable. True Quiz 3  Signal decompositio