Multiple Choice Quiz ON DATA,SIGNAL AND COMMUNICATION

The _______ is the physical path over which a message travels.
	A)	Protocol
	B)	Medium
	C)	Signal
	D)	All the above
2	The information to be communicated in a data communications system is the _______.
	A)	Medium
	B)	Protocol
	C)	Message
	D)	Transmission
3	Frequency of failure and network recovery time after a failure are measures of the _______ of a network.
	A)	Performance
	B)	Reliability
	C)	Security
	D)	Feasibility
4	An unauthorized user is a network _______ issue.
	A)	Performance
	B)	Reliability
	C)	Security
	D)	All the above
5	Which topology requires a central controller or hub?
	A)	Mesh
	B)	Star
	C)	Bus
	D)	Ring
6	Which topology requires a multipoint connection?
	A)	Mesh
	B)	Star
	C)	Bus
	D)	Ring
7	Communication between a computer and a keyboard involves ______________ transmission.
	A)	simplex
	B)	half-duplex
	C)	full-duplex
	D)	automatic
8	A television broadcast is an example of _______ transmission.
	A)	simplex
	B)	half-duplex
	C)	full-duplex
	D)	automatic
9	A _______ connection provides a dedicated link between two devices.
	A)	point-to-point
	B)	multipoint
	C)	primary
	D)	secondary
10	In a _______ connection, more than two devices can share a single link.
	A)	point-to-point
	B)	multipoint
	C)	primary
	D)	secondary
11	In _______ transmission, the channel capacity is shared by both communicating devices at all times.
	A)	simplex
	B)	half-duplex
	C)	full-duplex
	D)	half-simplex
12	In the original ARPANET, _______ were directly connected together.
	A)	IMPs
	B)	host computers
	C)	networks
	D)	routers
13	This was the first network.
	A)	CSNET
	B)	NSFNET
	C)	ANSNET
	D)	ARPANET
14	Which organization has authority over interstate and international commerce in the communications field?
	A)	ITU-T
	B)	IEEE
	C)	FCC
	D)	ISOC
15	_______ are special-interest groups that quickly test, evaluate, and standardize new technologies.
	A)	Forums
	B)	Regulatory agencies
	C)	Standards organizations
	D)	All of the above
16	Which agency developed standards for physical connection interfaces and electronic signaling specifications?
	A)	EIA
	B)	ITU-T
	C)	ANSI
	D)	ISO
17	_______ is the protocol suite for the current Internet.
	A)	TCP/IP
	B)	NCP
	C)	UNIX
	D)	ACM
18	_______ refers to the structure or format of the data, meaning the order in which they are presented.
	A)	Semantics
	B)	Syntax
	C)	Timing
	D)	All of the above
19	________ defines how a particular pattern to be interpreted, and what action is to be taken based on that interpretation.
	A)	Semantics
	B)	Syntax
	C)	Timing
	D)	None of the above
20	_______ refers to two characteristics: when data should be sent and how fast it can be sent.
	A)	Semantics
	B)	Syntax
	C)	Timing
	D)	none of the above
21	Data flow between two devices can occur in a _______ way.
	A)	simplex
	B)	half-duplex
	C)	full-duplex
	D)	all of the above
22	In a ______ connection, two and only two devices are connected by a dedicated link.
	A)	multipoint
	B)	point-to-point
	C)	(a) and (b)
	D)	none of the above
23	In a ________ connection, three or more devices share a link.
	A)	multipoint
	B)	point-to-point
	C)	(a) and (b)
	D)	none of the above
24	______ refers to the physical or logical arrangement of a network.
	A)	Data flow
	B)	Mode of operation
	C)	Topology
	D)	None of the above
25	Devices may be arranged in a _____ topology.
	A)	mesh
	B)	ring
	C)	bus
	D)	all of the above
26	A _______ is a data communication system within a building, plant, or campus, or between nearby buildings.
	A)	MAN
	B)	LAN
	C)	WAN
	D)	none of the above
27	A ______ is a data communication system spanning states, countries, or the whole world.
	A)	MAN
	B)	LAN
	C)	WAN
	D)	none of the above
28	________ is a collection of many separate networks.
	A)	A WAN
	B)	An internet
	C)	a LAN
	D)	None of the above
29	There are ______________ Internet service providers.
	A)	local
	B)	regional
	C)	national and international
	D)	all of the above
30	A ________ is a set of rules that governs data communication.
	A)	forum
	B)	protocol
	C)	standard
	D)	none of the above
31	________ is an idea or concept that is a precursor to an Internet standard.
	A)	RCF
	B)	RFC
	C)	ID
	D) http://highered.mcgraw-hill.com http://highered.mcgraw-hill.com/sites/0072967757/student_view0/chapter5/ Network Models * The five-layer model provides guidelines for the development of universally compatible networking protocols.* The physical, data link, and network layers are the network support layers. * The application layer is the user support layer. * The transport layer links the network support layers and the user support layer. * The physical layer coordinates the functions required to transmit a bit stream over a physical medium. * The data link layer is responsible for delivering data units from one station to the next without errors. * The network layer is responsible for the source-to-destination delivery of a packet across multiple network links. * The transport layer is responsible for the process-to-process delivery of the entire message. * The application layer enables the users to access the network. Data and Signals * Data must be transformed into electromagnetic signals prior to transmission across a network. * Data and signals can be either analog or digital. * A signal is periodic if it consists of a continuously repeating pattern. * Each sine wave can be characterized by its amplitude, frequency, and phase. * Frequency and period are inverses of each other. * A time-domain graph plots amplitude as a function of time. * A frequency-domain graph plots each sine wave’s peak amplitude against its frequency. * By using Fourier analysis, any composite signal can be represented as a combination of simple sine waves. * The spectrum of a signal consists of the sine waves that make up the signal. * The bandwidth of a signal is the range of frequencies the signal occupies. Bandwidth is determined by finding the difference between the highest and lowest frequency components. * Bit rate (number of bits per second) and bit interval (duration of 1 bit) are terms used to describe digital signals. * A digital signal is a composite signal with an infinite bandwidth. * Bit rate and bandwidth are proportional to each other. * The Nyquist formula determines the theoretical data rate for a noiseless channel. * The Shannon capacity determines the theoretical maximum data rate for a noisy channel. * Attenuation, distortion, and noise can impair a signal. * Attenuation is the loss of a signal’s energy due to the resistance of the medium. * The decibel measures the relative strength of two signals or a signal at two different points. * Distortion is the alteration of a signal due to the differing propagation speeds of each of the frequencies that make up a signal. * Noise is the external energy that corrupts a signal. * We can evaluate transmission media by throughput, propagation speed, and propagation time. * The wavelength of a frequency is defined as the propagation speed divided by the frequency.	none of the above