MIS 140 Chapter 3 Homework question
The medium is the physical matter or substance that carries the voice or data transmission. True False
True
Time division multiplexing is more efficient that frequency division multiplexing because the guardbands used in the frequency division multiplexing or not needed. True False
True
WDM is a version of FDM used in fiber-optic cables. True False
True
The height of a sound wave is called its: frequency phase amplitude bandwidth furlong
amplitude
In general, older networks and local loops designed to transmit voice data are likely to be ________. international level 2 numeric digital analog
analog
Another term for the weakening of a signal over distance is: turnaround time propagation delay dispersion insulation attenuation
attenuation
Which of the following is a characteristic of sound waves that can be modulated to convert digital data into analog signals? phase attenuation bipolar bandwidth codec
bipolar
____________ refers to the transmission characteristics of the circuit. handshaking virtual circuit bonding logical circuit physical circuit
logical circuit
Which of the following would be considered a type of wireless media? unshielded twisted pair shielded twisted pair coaxial cable microwave fiber optics
microwave
__________ is a line-of-sight type of wireless media. coaxial cable microwave radio twisted pair fiber optic
microwave
____________ refers to changing the shape of the sound wave in different ways to represent a 1 or a 0. digitizing. sampling modulation demodulation shaping
modulation
A(n) ___________ divides one high-speed communication circuit into several lower speed circuits for the primary reason of saving communication line costs. transponder multiplexer inverse multiplexer codec intelligent terminal
multiplexer
Frequency division multiplexing: operates by statistically time slicing the signal operates by dividing the signal into different frequencies uses a codec that divides signals into different channels operates by time slicing the signal operates by light dividing the signal
operates by dividing the signal into different frequencies
The direction in which the sound wave begins is known as: amplitude, which our ears detect as loudness frequency, which our ears detect as pitch phase bandwidth furlong
phase
Equipment used to transform analog voice signals to digital signals and digital signals to analog signals. voice converter modem codec multiplexer demodulator
codec
Which is not true about point-to-point circuits? point-to-point circuits are dedicated to the use of the two computers. point-to-point circuits are more expensive than multipoint circuits. point-to-point circuits are called dedicated circuits. point-to-point circuits reduce the amount of cable required and use the circuit more efficiently than multipoint circuits. point-to-point circuits are used when the computers generate enough traffic to fill the capacity of the communication circui
point-to-point circuits reduce the amount of cable required and use the circuit more efficiently than multipoint circuits.
________ is a modulation technique that combines two different amplitude combinations with eight different phase combinations modulation to send four bits per symbol. quadrature amplitude modulation time division multiplexing synchronous digital line control pulse code modulation baseband signaling
quadrature amplitude modulation
A(n) __________ circuit is another name for a multipoint configuration. analog dedicated point-to-point shared simplex
shared
When sending four bits at a time using frequency modulation, the number of different frequency levels that would be needed would be _______. 24 16 2 8 4
16
How many bits are required to sample an incoming signal 4000 times per second using 64 different amplitude levels? 64 32 16 8 6
6
Based on the TIA/EIA 568-B structured cabling standard, the cabling that runs from the telecommunications closet to each work area is called backbone cabling. True False
False
Baud rate is the number of bits transmitted per second. True False
False
Digital transmission occurs when the signal sent over the transmission media constantly varies among an infinite number of states. True False
False
Fiber optic cable carries signals in traditional electrical form. True False
False
Frequency division multiplexing divides the circuit into a set of different time slots. True False
False
Frequency modulation refers to the changing of the height of the sound wave. True False
False
Guided media refers to the type of media in which the message is broadcast through the air. True False
False
In a multipoint circuit configuration, each computer can use the circuit at the same time. True False
False
In a multipoint circuit configuration, each computer has a dedicated circuit between itself and each of the other computers in the network. True False
False
In simplex transmission, the data flows in both directions at the same time True False
False
Multimode fiber is capable of longer transmission distances than single mode fiber. True False
False
Multiplexing increases the cost of provisioning network circuits. True False
False
Multitasking means to break one high-speed physical communication circuit into several lower-speed logical circuits so that different devices can simultaneously use it. True False
False
Newer telephone circuits, built during the last decade, offer higher quality because they were built using analog transmission. True False
False
Nonreturn to zero is a type of unipolar signaling True False
False
Propagation delay is negligible with satellite transmission. True False
False
Radio, microwave and satellite are all examples of guided media. True False
False
Serial mode transmission is much faster than parallel mode transmission. True False
False
The amount of time it takes to switch between sending and receiving in half-duplex transmission is called the propagation delay. True False
False
Wavelength division multiplexing can only used with copper cables. True False
False
Wavelength division multiplexing can only used with copper cables. 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
With nonreturn to zero signaling, the voltage alternates between zero and a positive or negative voltage. True False
False
A walkie-talkie is an example of half-duplex transmission. True False
True
Amplitude, frequency and phase are all characteristics of a sound wave. True False
True
Coding schemes are groups of bits that translate into the "alphabet" of any given system. True False
True
Computers produce digital data whose values are binary: 0 or 1. True False
True
Data compression can increase the throughput of a communication link. True False
True
Digital transmission permits higher maximum transmission rates when compared to analog. True False
True
Ethernet, a common LAN technology, uses Manchester encoding. True False
True
Frequency is the number of cycles per second and is expressed in Hertz. True False
True
The "local loop" refers to the wires that run from the customer premises to the telephone switch of the telephone company. True False
True
The typical range of human hearing is: 0 to 4,000 Hz 0 to 1,200 Hz 20 to 14,000 Hz 0 to 300 Hz 0 to 56,000 Hz
20 to 14,000 Hz
With respect to converting digital data into analog signals, AM stands for: Asynchronous Manchester Analog Multimode Amplitude Modulation Anomaly Multiplexing Analytical Mosaic
Amplitude Modulation
A _________ is an FDM device that splits the physical circuit into three logical circuits (phone, upstream data, downstream data). DSL modem cable modem wireless router V.44 modem Serial modem
DSL modem
___________ is not a type of digital signaling technique. Non-return-to-zero signaling Unipolar signaling Manchester encoding Return-to-zero signaling Data rate signaling
Data rate signaling
A physical circuit refers to the transmission characteristics of the connection, such as the speed at which data is being sent through the connection. True False
False
ASCII is the least popular code for data communications. True False
False
_____________ can be thought of as dividing the circuit horizontally. Frequency division multiplexing Statistical frequency division multiplexing Statistical time division multiplexing Time division multiplexing Wavelength division multiplexing
Frequency division multiplexing
The earliest type of fiber optic systems were: Graded index multimode Attenuated Multimode Single mode Step mode
Multimode
Manchester encoding is a special type of bipolar signaling in which the signal is changed from high to low or from low to high in the middle of the signal. True False
True
Microwave transmissions require a line of sight between any two points. True False
True
One form of interference with satellite transmission is called raindrop attenuation in which the transmissions are absorbed by heavy rain. True False
True
Statistical time division multiplexing does not require the capacity of the circuit to be equal to the sum of the combined circuits. True False
True
Radio data transmission requires that each device has a radio receiver/transmitter and uses a specific frequency. True False
True
Signal bandwidth is the difference between the highest and lowest frequencies in a band. True False
True
______ is a modem standard that uses Lempel-Ziv encoding to compress data. V.22 V.44 V.32bis V.34 RS 232
V.44
___________ is used by IM and other applications that provide voice services over lower-speed digital circuits. pulse code modulation adaptive differential pulse code modulation Voice conversation code modulation phase modulation
adaptive differential pulse code modulation
Transmission speeds: are the same among all media are not a factor in selecting a media because all media have more than enough speed to serve current communication demands are a constant, 56Kbps, for all media types differ widely among media always have a direct correlation with security
differ widely among media
The representation of the character A by the group of 8 bits, 01000001, is an example of: digital coding phase modulation binary modulation analog transmission pitch variation
digital coding
___________ refers to the spreading of the signal that different parts of the signal arrive at different times at the destination. turnaround time propagation delay dispersion insulation attenuation
dispersion
A codec converts an incoming digital signal to an analog signal for transmission over an analog network. True false
false
Which of the following is the most secure wired media? coaxial cable unshielded twisted pair shielded twisted pair fiber optic cable infrared
fiber optic cable
Which of the following media has the lowest error rates and the highest transmission speeds? Coaxial cable unshielded twisted pair shielded twisted pair fiber optic cable infrared
fiber optic cable
Having a conversation with someone using a cellular phone is an example of _________ transmission. simplex full-duplex half-duplex analog digital
full-duplex
The two basic types of media are: statistical and frequency guided and wireless (radiated) local and wide area attenuator and Gaussian duplexed and non-duplexed
guided and wireless (radiated)
The ability to transmit in both directions, but only in one direction at a time is an example of _______________ transmission. simplex full-duplex half-duplex analog
half-duplex
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 satellites telephone lines boats modems
submarine cables
_____________ is not a form of modulation used to transform digital data into analog signals. synchronous time division amplitude shift keying amplitude modulation frequency modulation phase modulation
synchronous time division
The room that contains the cable termination points and the distribution frames is referred to as telecommunications closet equipment room building entrance backbone room work area
telecommunications closet
the type of multiplexer that divides the circuit horizontally into different light frequencies that are transmitted simultaneously across many channels is a: wavelength division multiplexer time division multiplexer statistical time division multiplexer frequency division multiplexer statistical frequency division multiplexer
wavelength division multiplexer
