intro to data communication hw quiz 3
When all bits of a character are transferred one after another, the bits are transferred in ___________ mode. a) serial b) frequency division c) multiplexing d) parallel e) full complex
a) serial
The two basic types of media are: a) statistical and frequency b) guided and wireless (radiated) c) local and wide area d) attenuator and Gaussian e) duplexed and non-duplexed
b) guided and wireless (radiated)
The height of a sound wave is called its: a) frequency b) phase c) amplitude d) bandwidth e) furlong
c) amplitude
Which type of digital signaling would experience fewer errors because it has more distinct signals a) unipolar b) serial c) bipolar d) attenuation e) Huffman encoding signal
c) bipolar
Equipment used to transform analog voice signals to digital signals and digital signals to analog signals. a) voice converter b) modem c) codec d) multiplexer e) demodulator
c) codec
The type of media usually installed on homes and businesses by the telephone company is called ____________. a) fiber optic cable b) coaxial cable c) twisted pair d) phone cable e) phone wire
c) twisted pair
Two fundamentally different types of data are: a) DSL and ADSL b) asymmetric and symmetric c) Microsoft and IBM d) digital and analog e) local area and wide area
d) digital and analog
Which of the following is the most secure wired media? a) coaxial cable b) unshielded twisted pair c) shielded twisted pair d) fiber optic cable e) infrared
d) fiber optic cable
Which of the following media has the lowest error rates and the highest transmission speeds? a) Coaxial cable b) unshielded twisted pair c) shielded twisted pair d) fiber optic cable e) infrared
d) fiber optic cable
A coding scheme that uses 10 bits to represent each character is capable of representing _________ different characters. a) 256 b) 20 c) 200 d) 512 e) 1024
e) 1024
Microwave transmission: a) is a type of high frequency radio communication b) requires a clear line-of-sight path c) is typically used for long distance data transmission d) does not require the laying of any cable e) all of the above
e) all of the above
Another term for the weakening of a signal over distance is: a) turnaround time b) propagation delay c) dispersion d) insulation e) attenuation
e) attenuation
In general, networks designed to transmit primarily computer data are likely to be ________. a) international b) level 1 c) numeric d) analog e) digital
e) digital
A codec converts an incoming digital signal to an analog signal for transmission over an analog network. true false
false
Coaxial cable costs less and offers less shielding to electrical interference than twisted pair cable. true false
false
Digital transmission produces more errors than analog transmission. true false
false
Fiber optic cable can only be used on LANs. true false
false
Guided media refers to the type of media in which the message is broadcast through the air. true false
false
Multimode fiber is capable of longer transmission distances than single mode fiber. true false
false
Propagation delay is negligible with satellite transmission. true false
false
With modem communications, the receiving modem converts the incoming digital signal from the telephone line into an analog signal that can be understood by the computer. true false
false
A walkie-talkie is an example of half-duplex transmission. true false
true
Frequency is the number of cycles per second and is expressed in Hertz. true false
true
In full-duplex transmission, two stations can send and receive simultaneously. true false
true
Of all the media available, fiber optic provides the highest transmission speeds. true false
true
