Chapter 1
Introduction to Data Communications
True-False Questions
The following are possible True/False questions for tests. The statement is given and the answer is
provided. The level of difficulty (easy, medium, hard), the reference section relevant to the topic, and
learning objective are also furnished.
1. According to John Chambers, CEO of Cisco (a leading networking technology company), the
information age is the second Industrial Revolution.
2. Due to advances in high speed communication networks, the information lag, or the time it takes for
information to be disseminated around the world, has been significantly shortened.
3. It is not uncommon for companies to end up spending more money on network management and
security tasks than they do on the actual computer equipment itself.
4. Telecommunications is the transmission of voice and video as well as data and usually implies
transmitting a longer distance than in a data communication network.
5. A local area network (LAN) connects other LANs and backbone networks (BNs) located in different
areas to each other and to wide area networks in a span from 3 to 30 miles.
6. An intranet is a LAN that uses Internet technologies and is publicly available to people outside of the
organization.
7. A car manufacturer may give access to certain portions of its network to some of its suppliers via the
Internet. This is an example of an extranet.
8. The OSI model is currently the most widely implemented network model used to develop and build
networks of any size, including the Internet itself.
9. The network layer performs the same functions in both the OSI and Internet models and is responsible
for routing messages from the source computer to the destination computer.
10. In the OSI model, the application layer provides a set of utilities for applications and is the end user’s
access to the network.
11. The application layer is the seventh layer of the Internet model and specifies the type of connection
and the electrical signals that pass through it.
12. At the transport layer in the Internet model, TCP is responsible for breaking large files received from
the application layer into smaller messages and opening a connection to a server for transferringthem.
13. Ethernet is an example of a network layer protocol.
14. Data communication standards enable each layer in the sending computer to communicate with its
corresponding layer in the receiving computer.
15. The specification stage of the de jure standardization process consists of developing nomenclature and
identifying the problems to be addressed.
16. ANSI is a voting participant in the ISO.
MULTIPLE CHOICE
The following are possible multiple-choice questions for tests. The question is posed and the answer is
provided under the choices. The level of difficulty (easy, medium, hard), the reference section relevant to
the topic, and learning objective are also furnished.
1.
Data communications and networking can be considered as a global area of study
because:
a. new technologies and applications emerge from a variety of countries and
spread around the world
b. the technologies enable global communication
c. the political and regulatory issues are exactly the same in every country
d. a and b
e. none of the above
2.
Which of the following is not true about a server?
a. stores data and software that can be accessed by the client.
b. may be a personal computer or a mainframe on the network.
c. in client/server computing they work together over the network with client
computers to support the business application.
d. can only perform one function on a network.
e. stores documents and graphics that can be accessed from any Web browser.
L.O.: Be familiar with the major components of and types of
3.
Networks that are designed to connect similar computers that share data and software
with each other are called:
a. client/server networks
b. peer-to-peer networks
c. host networks
d. client networks
e. local area networks
networks
4.
The function of the file server is to :
a. store data and software programs that can be used by client computers on the
network.
b. manage all printing requests from clients on the network.
c. transfer e-mail messages to other servers on the network.
d. store HTML documents for an Internet or intranet web site.
e. coordinate the communication of client and servers on the network.
5.
A local area network is:
a. a large central network that connects other networks in a distance spanning
exactly 5 miles.
b. a group of personal computers or terminals located in the same general area
and connected by a common cable (communication circuit) so they can
exchange informationsuch as a set of rooms, a single building, or a set of
well-connected buildings.
c. a network spanning a geographical area that usually encompasses a city or
county area (3 to 30 miles).
d. a network spanning a large geographical area (up to 1000s of miles).
e. a network spanning exactly 10 miles with common carrier circuits.
6.
A backbone network is:
a. a high speed central network that connects other networks in a distance
spanning up to several miles.
b. a group of personal computers or terminals located in the same general area
and connected by a common cable (communication circuit) so they can
exchange information.
c. a network spanning a geographical area that usually encompasses a city or
county area (3 to 30 miles).
d. a network spanning a large geographical area (up to 1000s of miles).
e. a network spanning exactly 200 miles with common carrier circuits.
7.
Which of the following is not a property of a WAN:
a. connects backbone networks and MANS.
b. spans hundreds or thousands of miles
c. provides data transmission speeds from 56Kbps to 10Gbps.
d. connects a group of computers in a small geographic area such as room, floor,
building or campus.
e. uses leased lines from IXCs like ATT, MCI, and Sprint.
8.
A(n) _________ is a LAN that uses the same technologies as the Internet but is open
to only those inside the organization.
a. WAN
b. BN
c. extranet
d. intranet
e. MAN
9.
A(n) _________ is a LAN that uses the same technologies as the Internet but is
provided to invited users outside the organization who access it over the Internet.
a. WAN
b. BN
c. extranet
d. intranet
e. MAN
networks
10.
Which layer of the OSI model is responsible for ensuring that all packets sent are
received by the destination station by dealing with end-to-end issues?
a. presentation
b. transport
c. physical
d. session
e. application
L.O.: Understand the role of network layers
11.
Which layer of the OSI model is responsible for ensuring flow control so that the
destination station does not receive more packets that it can process at any given
time?
a. presentation
b. transport
c. physical
d. session
e. application
12.
The ____________ layer of the OSI model is responsible for data format translation.
a. session
b. presentation
c. physical
d. application
e. transport
13.
The fourth layer of the OSI model is called the __________ layer.
a. network
b. transport
c. session
d. data link
e. presentation
14.
___________ is an orderly close to a dialogue between end users.
a. Session termination
b. Physical bits
c. Frame overhead
d. Packet encapsulation
e. Message encryption
15.
In the Internet model, the application layer corresponds to the ________ layer(s) of
the OSI model.
a. data link and network
b. session, presentation and application
c. application layer
d. application and presentation
e. network, transport and presentation
16.
The _________ layer performs error checking which is redundant to some extent
with the function of the _________ layer.
a. application, presentation
b. physical, data link
c. transport, data link
d. presentation, transport
e. network, physical
17.
Which is not a function of the physical layer:
a. transmission of bits.
b. defining the rules by which one and zeroes are transmitted.
c. providing error-free transmission of data.
d. providing the physical connection between sender and receiver.
e. specifying the type of connection and type of signals, waves or pulses that
pass though it.
18.
The _________ layer is responsible for routing of messages from the sender to the
final destination.
a. data communication layer
b. resident layer
c. application layer
d. network layer
e. physical layer
19.
Which of the following is not a function of the data link layer?
a. deciding when to transmit messages over the media
b. formatting the message by indicating where messages start and end, and
which part is the address
c. detecting and correcting any errors that have occurred in the transmission of
the message
d. specifying the type of connection, and the electrical signals, radio waves, or
light pulses that pass through it
e. controlling the physical layer by determining when to transmit
20.
Which of the following is a function of the transport layer?
a. linking the physical layer to the network layer
b. formatting messages by indicating where they start and end
c. deciding which route the message should take
d. breaking long messages into several smaller messages
e. specifying the type of connection and the electrical signals, radio waves, or
light pulses that pass through it
21.
Which of the following is a term used to group together the physical and data link
layers?
a. Internetwork layers
b. Hardware layers
c. Software layers
d. Middleware layers
e. Application layers
22.
Which of the following would be a standard used at the Data Link layer of the
Internet or OSI model?
a. IP
b. TCP
c. Ethernet
d. HTTP
e. FTP
23.
In which layer of the Internet model would the HTTP standard be used?
a. physical
b. application
c. transport
d. network
e. data link
24.
A(n) _____________ is a set of rules that determine what a layer would do and
provides a clearly defined set of messages that software at the layer needs to
understand.
a. agreement
b. standard
c. protocol
d. regulations
e. policy
25.
The network layer of the Internet model uses the _____________ protocol to route
messages though the network.
a. TCP
b. HTTP
c. FTP
d. SMTP
e. IP
26.
The primary reason for networking standards is to:
a. simplify cost accounting for networks
b. ensure that hardware and software produced by different vendors can work
together
c. make it more difficult to develop hardware and software that link different
networks
d. ensure that all network components of a particular network can be provided
by only one vendor
e. lock customers into buying network components from one vendor
27.
Which of the following is not true about de jure standards?
a. They are always developed before de facto standards.
b. One example exists for network layer software (IP).
c. They can be developed by an official industry body.
d. They can take several years to develop.
e. They can be developed by a government body.
28.
Which of the following is not true about de facto standards?
a. They never evolve into de jure standards.
b. They are those standards that emerge in the marketplace.
c. They tend not to be developed by an official industry or government
body.
d. They are generally supported by more than one vendor but de facto
standards have no official standing.
e. They tend to emerge based upon the needs/response of the marketplace.
29.
The three stages of the de jure standardization process are
______________________.
a. specification, identification of choices and acceptance.
b. planning, implementing and acceptance.
c. brainstorming, identification and implementing.
d. specification, formalization, and acceptance.
e. none of the above.
30.
Which of the following is true about ISO:
a. It makes technical recommendations about data communications
interfaces
b. Its name stands for International Organization for Standardization
c. It is based in Geneva, Switzerland
d. It is one of the most important standards-making bodies
e. All of the above
31.
Which of the following is not true about ITU-T:
a. It is the technical standards-setting organization of the United Nations
International Telecommunications Union
b. It is the International Telecommunications Union – Telecommunications
Group
c. Its membership is limited to U.S. telephone companies
d. It is based in Geneva, Switzerland
e. Its membership is comprised of representatives from over 200 member
countries
32.
The American National Standards Institute:
a. is the coordinating organization for the United States’ national system of
standards
b. is a professional society in the U.S. whose standards committees focus on
local area network standards
c. sets the standards that govern how much of the Internet will operate
d. is an agency that develops federal information processing standards for
the federal government
e. makes technical recommendations about global telephone rates
33.
The Internet standards organization that will allow anyone to join is
__________________.
a. ANSI
b. ISO
c. IETF
d. IEEE
e. ITU-T
34.
Which standards body is responsible for the development of local area network
(LAN) standards?
a. ANSI
b. ISO
c. IETF
d. IEEE
e. ITU-T
35.
Which of the following is not an application layer standard?
a. HTTP
b. POP
c. T1
d. IMAP
e. HTML
36.
Which of the following is not a data link layer standard?
a. HTTP
b. Ethernet
c. T1
d. PPP
e. Frame Relay
37.
Which of the following is not an important future trend in communication and
networking?
a. development of online batch systems
b. integration of voice, video, and data
c. pervasive networking
d. provision of new information services on rapidly expanding networks
e. development of extremely high speed broadband networks
38.
__________ ensure that hardware and software produced by different vendors work
together.
a. Delimiters
b. Standards
c. ASPs
d. RBOCs
e. Intranets
39.
A _____________ is the input-output hardware device at the end user’s end of a
communication circuit in a client-server network.
a. server
b. circuit
c. client
d. host
40.
A(n) ___________ is similar to an intranet in that it uses Internet technologies, but is
developed for users outside the organization.
a. intranet
b. Usenet
c. Wide Area Network
d. extranet
41. Taken together, the physical and data link layers are called the ____________________.
a. Internet layer
b. Hardware layer
c. Internetwork layer
d. Application layer
42. BYOD stands for
a. Bring Your Own Device
b. Bring Your Own Database
c. Build Your Own Device
d. Build Your Own Database
43. When a user accesses an application via a web browser on their mobile device, this is
referred to as
a. a browser-based approach
b. a native app
c. Internet Explorer
d. BYOD
44. A MOOC is an example of a(n)
a. BYOD
b. massively online technology
c. native app
d. browser-based technology
45. A network administrator has received several reports from users of the network that the
intranet website on one of company servers is not accessible, but the same users are still able
to retrieve their email being stored on the same server. What layer of the Internet model does
this problem appear to reside at?
a. physical
b. transport
c. network
d. application
e. data link
46. A junior network administrator has used the wrong cable type to connect his/her computer to
the administrative port on a router and cannot establish a terminal session with the device.
What layer of the Internet model does this problem appear to reside at?
a. physical
b. transport
c. network
d. application
e. data link
47. Which of the following correctly represents order of the seven layers of the OSI model from
layer 1 to layer 7?
a. physical, network, data link, session, transport, application, presentation
b. physical, data link, network, transport, session, application, presentation
c. physical, data link, network, transport, session, presentation, application
d. data link, physical, network, session, transport, application, presentation
e. data link, physical, network, transport, session, presentation, application
SHORT ANSWER AND ESSAY
1. How can data communications networks affect businesses?
2. From your own knowledge or background, discuss and describe three important
applications of data communications networks for strategic, competitive advantage in
business use. Give examples of three real world firms who have used networks for
competitive advantage in the marketplace and discuss why these networks contributed to
their expertise or competitive advantage.
3. How do LANs differ from WANs, and BNs?
4. Draw a diagram of the Internet model and describe what each of the five layers do. Put
three examples of standards on each of your layers in the diagram. Do this in detail,
explaining how a message is transmitted from one computer to another using this model.
5. How are Internet standards developed? What is a de facto standard?
6. Describe two important data communications standards-making bodies. How do they
differ?
7. What is the purpose of a data and network communication standard? Give five examples
of various standards and describe what that standard is (e.g., RS 232, HTTP, etc.)
8. Discuss three trends in communications and networking. Be sure to give four points for
each of these trends, plus two in depth examples in your response.
9. Compare and contrast a backbone network (BN), a LAN, and a WAN. Do most
organizations build WANs?
10. What are the three basic hardware components for a data communication network?
Describe the functions of these.
11. Why are standards important?
12. Describe the address naming structure of computers on the Internet.
13. What is the difference between an extranet and intranet?
14. What are the seven layers of the OSI model and what does each of these layers do? How
does the OSI model compare to the Internet model? What does OSI stand for, and who
developed this model?
15. What is VOIP? What are some examples of companies that provide VOIP as a service to
their customers?
16. Explain why it is such a great time to be an IT professional.