ITN 100 Chapter 3 Study Guide
In general, networks designed to transmit primarily computer data are likely to be ________.
digital
The representation of the character A by the group of 8 bits, 01000001, is an example of:
digital coding
Which of the following media has the lowest error rates and the highest transmission speeds?
fiber optic cable
Having a conversation with someone using a cellular phone is an example of _________ transmission.
full-duplex
The two basic types of media are:
guided and wireless (radiated)
The ability to transmit in both directions, but only in one direction at a time is an example of _______________ transmission.
half-duplex
To get more "bandwidth" in a digital transmission, you must:
increase the range of frequencies available for a transmission
__________ is a line-of-sight type of wireless media.
microwave
A(n) ___________ divides one high-speed communication circuit into several lower speed circuits for the primary reason of saving communication line costs.
multiplexer
Frequency division multiplexing:
operates by dividing the signal into different frequencies
Data is physically transmitted from one computer or terminal to another in the ________ layer.
physical
Which is not true about point-to-point circuits?
point-to-point circuits reduce the amount of cable required and use the circuit more efficiently than multipoint circuits
Which of the following is not an important factor to consider when selecting media to be used in a network?
prestige value of the type of media
_____________ refers to the difference between the original analog data and the approximation of that data using the techniques for translating from analog data to digital signals.
quantizing error
A(n) __________ circuit is another name for a multipoint configuration.
shared
Time (non-statistical) division multiplexing differs from frequency division multiplexing because it:
splits the communication circuit vertically (with time slots) instead of horizontally
When sending four bits at a time using frequency modulation, the number of different frequency levels that would be needed would be _______.
16
The typical range of human hearing is:
20 to 14,000 Hz
How many bits are required to sample an incoming signal 4000 times per second using 64 different amplitude levels?
6
When converting analog voice data to digital signals, Pulse Code Modulation typically samples the incoming voice signal _______ times per second
8,000
When you send an email from the US to Europe, it likely is transmitted from one continent to another through one of the ______ that connect America and Europe.
submarine cables
The type of media usually installed on homes and businesses by the telephone company is called ____________.
twisted pair
_____________ can be thought of as dividing the circuit horizontally.
Frequency division multiplexing
Which of the following is not a key advantage of digital transmission?
It permits only low transmission rates.
Ethernet uses
Manchester encoding
The acronym, Modem, stands for _________________.
Modulator/demodulator
The earliest type of fiber optic systems were:
Multimode
______ is a modem standard that uses Lempel-Ziv encoding to compress data.
V.44
___________ is commonly used to transmit phone conversations over digital networks.
VOIP
Another term for the weakening of a signal over distance is:
attenuation
A coding scheme that uses 10 bits to represent each character is capable of representing _________ different characters.
1024
If each sample uses 16 bits and the number of samples taken each second is 8000; then the transmission speed on the circuit is?
128 Kbps
The height of a sound wave is called its:
Amplitude
With respect to converting digital data into analog signals, AM stands for:
Amplitude Modulation
A _________ is an FDM device that splits the physical circuit into three logical circuits (phone, upstream data, downstream data).
DSL modem
___________ is not a type of digital signaling technique.
Data rate signaling
Two fundamentally different types of data are:
Digital and analog
Which of the following statements is correct?
Serial transmission is slower than parallel transmission.
____________ is used by IM and other applications that provide voice services over lower-speed digital circuits.
adaptive differential pulse code modulation
Microwave transmission:
all of the above *is typically used for long distance data transmission *is a type of high frequency radio communication *does not require the laying of any cable *requires a clear line-of-sight path
The _____________ of a circuit determines a circuit's capacity
bandwith
Which type of digital signaling would experience fewer errors because it has more distinct signals?
bipolar
Which of the following is the most secure wired media?
fiber optic cable
Which of the following media can best withstand harsh environmental conditions?
fiber optic cable
Which of the following is a characteristic of sound waves that can be modulated to convert digital data into analog signals?
phase
In which type of modulation is a 1 distinguished from a 0 by shifting the direction in which the wave begins?
phase modulation
With which type of digital signaling does the signal always return to zero volts after each bit?
return-to-zero signaling
When all bits of a character are transferred one after another, the bits are transferred in ___________ mode.
serial
_____________ is not a form of modulation used to transform digital data into analog signals.
synchronous time division
The room that contains the cable termination points and the distribution frames is referred to as
telecommunications closet