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Networks
& Communications (COMP277/L)
Student Practical
Handbook
Dr. Mohamed Aissa
Room 11 I-13
Content
1 Introduction to Computer Communication Networks 2 Network Classifications 3 Network Media 4 Network Devices 5 Open System Interconnection Model 6 Protocols
l
TOPIC 1
Exercise 1
Introduction
Introduction
Student Practical Handbook Comp277 /L
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Exercise No
1
Introduction
Related Topic: 1 Introduction
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Define some basic terminologies.
Recognize a communication model and define its basic components.
Recognize a data communication model and define its basic components.
Define a data flow and the different data directions at different transmission times.
Determine the main connection types.
Question 1
In all the following sentences circle the right answer.
1. Which of the following best describes the term telecommunications?
a. Communication with remote control.
b. Communication at distance.
c. Communication assisted by televisions.
2.Which of the following best describes the term data?
a. Numbers, characters, symbols images etc., which can be processed by a
computer.
b. Processed facts, statistics used for reference or analysis.
c. Information related to a defined subject.
3.Which of the following best describes the term information?
a. Numbers, characters, symbols images etc., which can be processed by a
computer.
b. Knowledge derived from study, experience (by the senses), or instruction.
c. Any kind of knowledge that is exchangeable amongst people, about things,
facts, concepts, etc., in some context. " Information is interpreted data".
Introduction
Student Practical Handbook Comp277 /L
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4. Which of the following best describes the term data communication?
a. The data processing to solve any problem related to communication.
b. Information system data processing.
c. The exchange of data between two devices via some form of transmission
medium such as a wire cable.
Question 2
1. The following figures represent a communication model (figure (a)) and an
example (figure b). Fill in the boxes in the figure (a) with the appropriate
designations and write in figure (b) the corresponding examples.
Fig. 1: Communication Model
2. The following figures represent a communication model and the type of signals
generated at different phases of the data transmission process in a data
communication model. Fill in the following table with the appropriate signal types
generated at each phase (2, 3, 4, 5).
Introduction
Student Practical Handbook Comp277 /L
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Fig.2 Data Communication Model
Phase 2 Phase 3 Phase 4 Phase 5
Signal Type
3. The following figure contains the main components of data communication. Write
the designation of each component in this figure.
Fig.3 Main Components of Data Communication
Introduction
Student Practical Handbook Comp277 /L
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4. Fill in the following table with the appropriate data flow type according to the
direction(s) of data.
Data Direction(s) Data Flow Type
5. Fill in the following table with the appropriate connection type for each figure.
Connection Type
Student Practical Handbook Comp277 /L
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TOPIC 2
Exercise 1
Network Classifications
Exercise 2 Network Classifications
Student Practical Handbook Comp277 /L
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Exercise No
2
Network Classifications
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Define the basic types of network classifications.
Analyze and compare the basic network topologies.
Analyze and compare peer-to-peer and client/server networks.
Analyze and compare LAN, MAN and WAN networks.
Analyze and compare transmission data methods in the basic network topologies.
1.Which of the following best describes a characteristic existing in a Local Area Network
(LAN)? a. Internal data rates greater than WAN.
b. External data rates greater than WAN.
c. External data rates less than WAN.
2. Which of the followings are usually owned by the same organization that owns
attached devices:
a. LAN.
b. MAN
c. WAN
3. Which of the followings is usually called when the number of computer is fewer
than 100, and it does not require a router
a. LAN.
b. MAN
c. WAN
4. Which of the following best describes a Metropolitan Area Network (MAN)?
a. It covers a geographic area such as a town, city or suburb.
b. It covers a geographic area such as a building.
c. It covers a geographic area such as a continent.
5. Which of the following devices provides access to resources and services?
a. A client.
b. A server.
c. Any ordinary computer.
Exercise 2 Network Classifications
Student Practical Handbook Comp277 /L
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6. Which of the following devices requests access to the resources or services?
a. A client.
b. A server.
c. Any ordinary computer.
7. Which of the following topologies corresponds to the topology depicted in the
Fig.1?
a. A peer-to-peer.
b. A server based network (Client/Server)
c. Other type.
Fig. 1
8. In a defined network type, every user must also act as a network administrator,
controlling access to the resources on their machines. Which of the following best
describes this network:
a. A peer-to-peer network.
b. A server based network
c. Other type.
9. If your network contains more than ten computers, then you should choose the
following network:
a. A peer-to-peer network.
b. A server based network
c. Any other network.
Exercise 2 Network Classifications
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10. In a client/ Server topology, we can have the following events:
a. Client program sends Request message, such as a database retrieval request.
b. Server program sends a Response message to deliver the requested information
or an explanation for failure.
c. Client program sends a Response message to deliver the requested information
or an explanation for failure.
d. Server program sends Request message, such as a database retrieval request.
11. Which of the followings topologies have very high speed links over long
distances?
a. Ring.
b. Star.
c. Bus
12. Which of the followings topologies is best for short distances?
a. Ring.
b. Star.
c. Bus
13. Which of the followings topologies has high data rates for small number of
devices?
a. Ring.
b. Star.
c. Bus
Let's consider the following bus topology (Fig. 2).
Fig. 2
Exercise 2 Network Classifications
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14. If computer 1 is printing a large file, which of the following situation(s) is (are)
realistic?
a. All networking devices will see computer's 1 data traffic to the printer.
b. Only some of networking devices will see computer's 1 data traffic to the
printer.
c. None of networking devices will see computer's 1 data traffic to the printer.
d. other
15. If computer 1 is printing a large file, which of the following situation(s) is (are)
realistic?
a. All networking devices will wait for pauses in transmission or until it is
complete before they can initiate their own transmission.
b. All networking devices can initiate their own transmission at any time.
c. Some networking devices can initiate their own transmission however other
devices should wait.
d. other
16. Let's suppose that more than one computer's data is placed on the network at the
same time. Which of the following situation(s) is (are) realistic?
a. The data will be transmitted correctly to all receivers.
b. The data will be corrupted and must be retransmitted.
c. Some networking devices will receive the data, and others will not.
d. other
Exercise 2 Network Classifications
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Let's consider the following token-ring topology (Fig. 3).
Fig. 3
17. In a token-ring topology, a "token" (shown as a T) is placed in the data channel
and circulates around the ring. What happens if a user wants to transmit?
a. His computer waits until it has control of the token.
b. His computer transmits its data and then waits to get the token.
c. His computer transmits its data independently of the token.
d. other
18. A token-ring network is a deterministic network. What this means?
a. Each station connected to the network is assured access for transmission of its
message at different time intervals.
b. Each station connected to the network is assured access for transmission of its
message at regular or fixed time intervals.
c. Each station connected to the network is assured access for transmission of its
message at variable time intervals.
d. other
Exercise 2 Network Classifications
Student Practical Handbook Comp277 /L
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Let's consider the following star topology (Fig. 4):
Fig. 4
19. What kind of devices can be at the center of a star network to provide the
network connection?
a. A hub.
b. A switch
c. A multiplexer
d. Any other device
20. The hub is a multiport repeater. If a hub is used at the center of a star network,
then which of the following situation is realistic?
a. The data received from the sender is broadcast to all devices connected to the
ports of the hub.
b. The data received from the sender is broadcast to only one device which is the
receiver itself.
c. The data received from the sender is kept at the hub to assure its integrity.
d. Other
Exercise 2 Network Classifications
Student Practical Handbook Comp277 /L
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21. To minimize unnecessary data traffic, and isolate sections of the network, which
device among the followings is used at the center of a star network?
a. A hub.
b. A switch
c. A multiplexer
d. Any other device
22. If a switch is used at the center of a star network, then we have the following fact:
a. The data received from the sender is broadcast to all devices connected to the
ports of the hub.
b. The data received from the sender is broadcast to only one device which is the
receiver itself.
c. The data received from the sender is kept at the hub to assure its integrity.
d. other
Student Practical Handbook Comp277 /L
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TOPIC 3
Exercise 1
Transmission Media
Exercise 3 Transmission Media
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Exercise No
3
Transmission Media
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Analyze and compare the basic classifications of transmission media.
Analyze and compare the basic characteristics of guided media.
Analyze and compare the basic characteristics of unguided media.
Analyze and compare the different types of cables.
Question 1
1. Which of the following best describes a transmission media?
a. It is the physical path between transmitter and a receiver.
b. It is the logical path between transmitter and a receiver.
c. It is the logical path between sender and receiver.
d. other
2. Which of the following best describes guided media?
a. Waves are guided along a soft medium path.
b. Waves are guided along a solid medium path (twisted pair, coaxial cable, and optical fiber).
c. waves are propagated through the atmosphere and inner/outer space
d. other
3. Which of the following best describes unguided media?
a. Waves are guided along a soft medium path.
b. Waves are guided along a solid medium path (twisted pair, coaxial cable, and optical fiber).
c. waves are propagated through the atmosphere and inner/outer space
d. other
Exercise 3 Transmission Media
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4. Which of the following best describes unguided media?
a. Use high frequency radio signals or infrared light beams to communicate between the
workstations and the server
b. Use low frequency radio signals or light beams to communicate between the workstations and
the server.
c. Use medium frequency TV signals or sound beams to communicate between the workstations
and the server.
d. other
5. What gives higher bandwidth?
a. Lower data rate.
b. Higher data rate.
c. Less services.
d. Others.
6. What are the influences of transmission impairments such as attenuation?
a. Increase the bandwidth.
b. Increase the distance.
c. Limit the distance.
d. Others.
7. What are the influences of overlapping frequency bands?
a. Can amplify the signal.
b. Can distort the signal.
c. Can improve the signal.
d. Others.
8. Which of the following needs transceiver/antenna to send and receive data
a. Guided media.
b. Unguided media.
c. Passive media.
d. Others.
9. Which of the following has poor security?
a. Guided media.
b. Unguided media.
c. Passive media.
d. Others.
10. Which of the following is susceptible to electrical interference from lights and radios?
a. Unguided media.
b. Guided media.
c. Passive media.
d. Others.
Exercise 3 Transmission Media
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11. Which of the following is expensive?
a. Unguided media.
b. Guided media.
c. Passive media.
d. Others.
12. Which of the following best describes an antenna?
a. Unguided media.
b. Mechanical conductors used to radiate or collect electromagnetic energy.
c. Electrical conductors used to radiate or collect electromagnetic energy.
d. Others.
13. Which of the following best describes a communication satellite?
a. a microwave relay station.
b. An ordinary station.
c. An electric station.
d. Others.
14. Which of the following best define the using purpose of a communication satellite?
a. to separate two or more stations.
b. to link two or more ground stations
c. to link two or more computers.
d. Others.
15. Which of the following best describes a communication satellite task?
a. Decreases the signal.
b. Attenuates the signal.
c. receives on one frequency, amplifies or repeats signal and transmits on another frequency
d. Others.
Exercise 3 Transmission Media
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Question 2
1. Fill in the following table with the appropriate cable designation.
Cable Designation
Exercise 3 Transmission Media
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2. Fill in the following table with the appropriate media designations.
Media Using Purpose Media Designation
They are used for multicast communications, such as radio and television,
and paging systems.
They are used for unicast communication such as cellular telephones,
satellite networks, and wireless LANs.
They can be used for short-range communication in a closed area using
line-of-sight propagation.
3. Fill in the following table with the appropriate transmission media type (guided, unguided).
Transmission Media Transmission Media
Type
Twisted pair, coaxial cable, optical fibre
Antennas, terrestrial microwave, satellite microwave, broadcast radio
Ground wave, sky wave, line of sight
Network Devices
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TOPIC 4
Exercise 1
Network Devices
Exercise 4 Network Devices
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Exercise No
4 Network Devices
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Recognize the basic network devices.
Analyze and compare the serial and parallel data transmission processes
Recognize the network interface card (basic components, characteristics, tasks,…
Define a network segmentation,
Define the role of each network device,
Determine the advantages and the backwards of some network devices,
Determine the differences between some network devices,
1.Which of the following best describes the roles of network devices?
a. Expand or connect networks.
b. Can control the amount of traffic on a network.
c. Can speed up the flow of data over a network.
d. None of the above
2. Which of the following best describes the possibility of expanding a network?
d. Networks can be expanded by simple adding more servers or cabling.
e. Networks can be expanded by adding connectivity devices.
f. Networks can be expanded by extracting connectivity devices.
g. None of the above
3.Which of the following best describes the term creating larger networks?
a. Physically expand the network and segment network to filter traffic
b. Extend network to connect separate LANs
c. Connect two separate computer environments
d. None of the above
Exercise 4 Network Devices
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4.Which of the following are related to two crucial tasks of a network interface cars?
a. Establishes and manages the computer’s network connection
b. Connect the different parts of a motherboard
c. Translates digital computer data into signals (appropriate for the networking medium) for
outgoing messages, and translates signals into digital computer data for incoming messages
d. None of the above
5. The data transmission between the central unit and the different computer internal components is
done through
a. A set of parallel lines (also called buses).
b. A set of serial lines.
c. A set of mixed lines
d. None of the above
6. The transmission between the different network components is done through
a. A set of parallel lines.
b. A set of serial lines.
c. A set of mixed lines
d. None of the above
7. The transmission through a set of parallel lines is
a. A fast transmission.
b. A slow transmission.
c. A medium transmission
d. None of the above
8. The transmission through a set of serial is
a. A fast transmission.
b. A slow transmission.
c. A medium transmission
d. None of the above
9. The network card must deal with two kinds of speeds (fast and slow). Therefore, it should:
a. Deal with these two kinds of speeds and provide a balance between them.
b. Ignore the elements working under a slow speed.
c. Prioritize the elements working under a fast speed.
d. None of the above
10. The network card must deal with two kinds of speeds (fast and slow). For that purpose:
a. The network card stores the data into a ROM (read only memory).
b. The network card stores the data into a temporary memory that is a buffer.
c. The network card stores the data into a PROM (Programmable ROM).
d. None of the above
Exercise 4 Network Devices
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11. The number of nodes on a network and the length of cable used :
a. Strength the transmitted signal.
b. Improve the transmitted signal quality
c. Influence the quality of communication on the network. It attenuates the transmitted signal.
d. None of the above
12. Which of the following best describes the roles of the repeater?
a. Clean and regenerate the digital transmission in the process
b. Work against attenuation by repeating signals that they receive on a network
c. Divide the transmitted signal.
d. None of the above
13. Network segmentation using repeaters
a. Is Possible
b. Is not possible.
c. Depends on the repeater type.
a. None of the above
14. Which of the following best describes a hub?
a. A monoport repeater
b. A repeater
c. A multiport repeater.
d. None of the above
15. Which of the following best describes a hub?
a. Can be used to create multiple levels of hierarchy of stations
b. Can be used to create a mono level of hierarchy of stations
c. Can be used to create ordinary connected stations
d. None of the above
16. A multiple levels hierarchy of connected stations:
a. Is difficult to maintain and diagnose
b. Is easy to maintain and diagnose
c. Has not any advantages
d. None of the above
17. A hub can be used to connect two networks which should have:
a. Different topologies
b. Same topologies
c. Different or similar topologies
d. None of the above
Exercise 4 Network Devices
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18. A hub which amplifies or repeat signals that pass through them is
a. A passive hub
b. An active hub
c. A neutral hub
d. All of the above
19. Hubs are often used in the following topology (topologies):
a. Star-wired ring
b. An active hub
c. Star
d. All of the above
20. Hubs are also called:
a. Switches
b. Buses
c. Concentrators
d. None of the above
21. Hubs can connect
a. different network architectures, such as Token Ring and Ethernet
b. only similar network architectures.
c. only equal network architectures.
d. None of the above
22. Hubs can
a. not reduce network traffic.
b. reduce network traffic.
c. Adjust network traffic.
d. None of the above
23. Network segmentation using Hubs
a. Is Possible
b. Is not possible.
c. Depends on the hub type.
d. None of the above
24. Hubs can connect networks that require
a. different types of frames
b. similar types of frames
c. any types of frames
d. None of the above
Exercise 4 Network Devices
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25. Which of the followings best describe "network segmentation":
a. The breaking down of a single slightly populated network segment into bigger segments,
or collision domains, populated by fewer nodes
b. The breaking down of a single slightly populated network segment into smaller segments,
or collision domains, populated by many nodes
c. The breaking down of a single heavily populated network segment into smaller segments,
or collision domains, populated by fewer nodes
d. None of the above
26. Which of the followings best describe "a network segment":
a. A network that is linked with another network
b. Part of a network that is combined logically or physically with the rest of the network
c. Part of a network that is divided logically or physically from the rest of the network
d. None of the above
27. Which of the followings best describe "a network segment"?
a. A network that is linked with another network
b. Part of a network that is combined logically or physically with the rest of the network
c. Part of a network that is divided logically or physically from the rest of the network
d. None of the above
28. When network administrators place too many nodes on the same network segment, which of
the followings best describe the consequences?
a. This causes the number of collisions to increase
b. This causes the number of collisions to decrease
c. This causes the number of collisions to be moderated
d. None of the above
29. Which of the followings best describe the functions of a bridge?
a. Filter traffic between network segments
b. Reduce network traffic by keeping local traffic on the local segment
c. Amplify signals
d. None of the above
30. Which of the followings best describe the functions of a bridge?
a. Divide a large network into smaller segment
b. Isolate and control the link problems (e.g. congestion)
c. Regenerate signal and check Physical Address and forward only to the specified segment
d. None of the above
Exercise 4 Network Devices
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Let's analyze the following flowchart depicted in Fig. 1 and which is related to bridge
forwarding process:
Fig. 1: Bridge Forwarding
31. Which of the followings best describe the action taken in box "A"?
a. Forward frame on all LAN without exception
b. Forward frame on some LAN which are the nearest to port x.
c. Forward frame on all LAN except port x.
d. None of the above
32. Which of the followings best describe the action taken in box "B"?
a. Forward frame to the correct LAN
b. Forward frame on some LAN which are the nearest to port x.
c. Forward frame on all LAN except port x.
d. None of the above
Exercise 4 Network Devices
Student Practical Handbook Comp277/L
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33. Which of the followings best describe the action taken in box "C"?
a. Forward frame to the correct LAN
b. Forward frame on some LAN which are the nearest to port x.
c. Count frame discarded.
d. None of the above
Let's analyze the following scenario depicted on Fig. 2. We propose here some bridge-
forwarding tables.
Fig. 2: Creation of a bridge-forwarding table
Addresses Ports
Addresses Ports
Addresses Ports
A 1 A 1 A 1
B 1 B 1 B 1
C 2 C 2 C 2
D 3 D 3 D 3
E 4 E 3 E 3
F 4 F 3 F 4
Table 1 Table 2 Table 3
Exercise 4 Network Devices
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34. Which of the followings best describe bridge-forwarding table?
a. Table 1
b. Table 2
c. Table 3
d. None of the above
35. In which process, learning bridges build a table of MAC addresses?
a. as they receive frames
b. as they hear destination hosts
c. When data is processed
d. None of the above
36. In order to determine which addresses are on which segments, which type of addresses learning
bridges use?
a. Destination MAC addresses
b.Source MAC addresses
c. IP addresses
d. None of the above
37. Translation bridges can connect networks
a. with similar architecture
b. with particular architecture
c. with different architecture
d. None of the above
38. Comparing Bridges with repeaters with hubs, we can conclude that:
a. Bridges are faster than repeaters and hubs
b. Bridges are as fast as repeaters and hubs
c. Bridges are slower than repeaters and hubs
d. None of the above
39. Comparing Bridges with repeaters with hubs, we can conclude that:
a. Bridges are less expensive than repeaters and hubs
b. Bridges, repeaters and hubs have equal costs
c. Bridges are more expensive than repeaters and hubs
d. None of the above
Answer Sheet Topics: 2, 3 and 4
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Assignment 1 - Answer Sheet
Student Name:
Questions Topic 2 Topic 3 Topic 4
a b c d a b c d a b c d 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40.
Student Practical Handbook Comp277/L
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TOPIC 5
Exercise 1
Open System
Interconnection Model
Exercise 5 OSI Model
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Exercise No
5 Open System
Interconnection Model
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Define and Know the Open System Interconnection Model
Define and determine the role of each layer of the OSI Model
1. Which of the followings best describe the term "OSI model"?
a. A reference tool for understanding data communications between any two networked
systems.
b.A general tool for collecting data communications between any two networked systems.
c. A general tool for assembling data communications between any two networked systems.
d. None of the above.
2. Which of the followings best describes the function(s) of the layers of the "OSI model"?
a. Each layer performs specific functions to support the layers above it and offers services to
the layers below it.
b.Each layer performs general functions to support any layers of the OSI model.
c. Each layer both performs specific functions to support the first and last layers in the OSI
model.
d. None of the above.
3. The lower layers of the OSI model
a. Are three layers and handle data transport issues.
b. Are four layers and handle data transport issues.
c. Are four layers and they handle applications issues.
d. None of the above.
4.The upper layers of the OSI model
a. Are four layers with application issues.
b. Are four layers and they handle data transport issues.
c. Are three layers and they handle applications issues.
d. None of the above.
Exercise 5 OSI Model
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5. The physical layer and the data link layer are implemented
a. in hardware and software
b. Only in hardware.
c. Only in software
d. None of the above.
6. The upper layers of the OSI model are generally implemented
a. in hardware and software
b. Only in hardware.
c. Only in software
d. None of the above.
Exercise 5 OSI Model
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1. For each definition in the following table, write the appropriate OSI layer.
Layer Definition
This layer is responsible for addressing messages and data so they are sent to the
correct destination, and for translating logical addresses and names (like a machine
name FLAME) into physical addresses. This layer is also responsible for finding a
path through the network to the destination computer.
This layer allows two applications to establish, use and disconnect a connection
between them called a session. This layer provides for name recognition and
additional functions like security, which are needed to allow applications to
communicate over the network.
This layer defines connector and interface specifications, as well as the medium
(cable) requirements. Electrical, mechanical, functional, and procedural specifications
are provided for sending a bit stream on a computer network.
This layer provides an interface for the end user operating a device connected to a
network.
This layer is what the user sees, in terms of loading an application (such as Web
browser or e-mail); that is, this application layer is the data the user views while using
these applications.
This layer ensures that data is delivered error free, in sequence and with no loss,
duplications or corruption. This layer also repackages data by assembling long
messages into lots of smaller messages for sending, and repackaging the smaller
messages into the original larger message at the receiving end.
This layer takes the data frames or messages from the Network Layer and provides
for their actual transmission. At the receiving computer, this layer receives the
incoming data and sends it to the network layer for handling. This layer also provides
error-free delivery of data between the two computers by using the physical layer. It
does this by packaging the data from the Network Layer into a frame, which includes
error detection information. At the receiving computer, this layer reads the incoming
frame, and generates its own error detection information based on the received frames
data. After receiving the entire frame, it then compares its error detection value with
that of the incoming frames, and if they match, the frame has been received correctly.
This layer determines the format used to exchange data among networked computers.
Student Practical Handbook Comp277/L
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TOPIC 6
Exercise 1
Protocols
Exercise 6 Protocols
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Exercise No
6
Protocols
STUDENT LEARNING OUTCOMES:
Upon completion of this exercise,, a successful student will be able to:
Define a protocol.
Identify the key elements of a protocol,
Define the "Layering" and its benefits
Analyze and compare the different types of protocols
1.Which of the followings best describe the term "protocol"?
a. a set of instructions saved in the computer RAM
b. a set of instructions saved in the computer ROM
c. a set of devices implemented in stand- alone computers.
d.a set of rules that governs the communications between computers on a network.
2.How protocols can be implemented?
a. In hardware
b.In software
c. In a mixture of hardware and software
d. None of the above
3. Concerning protocol implementation, we observe in general the following
situation:
a. the lower layers are implemented in hardware, with the higher layers being
implemented in software
b. the higher layers are implemented in hardware, with the lower layers being
implemented in software
c. the lower layers are implemented in hardware, with the higher layers being
implemented in software
d. None of the above
4. Actual communication is defined by:
a. the OSI model
b.various communication protocols
c. some types of the OSI model
d. All of the above
Exercise 6 Protocols
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5.Which of the following best describes the term "Layering"?
a. Layering is a design principle which divides the protocol design into a number
of smaller parts, each part accomplishing a particular sub-task and interacting
with the other parts of the protocol only in a small number of well-defined
ways.
b. Layering is a design principle which combines the protocol design with a
number of smaller parts, each part accomplishing a random sub-task and is
isolated at the other parts of the protocol.
c. Layering is a the process of analyzing the protocol design and its smaller parts.
Each part accomplishing a particular sub-task and interacting with the other
parts of the protocol only in a small number of well-defined ways.
d. All of the above
6. Which of the following best describe the benefits of layering?
a. Layering allows the parts of a protocol to be designed and tested without a
combinatorial explosion of cases, keeping each design relatively simple.
b. Layering permits familiar protocols to be adapted to unusual circumstances.
c. Layering has many advantages
d. None of the above
7. Which of the following best describe the key elements of a protocol?
a. Syntax, semantics, measures.
b. Syntax, object, timing.
c. Syntax, Subject, timing.
d. Syntax, semantics, timing.
8. Which of the following best describe the term "syntax"?
a. the structure or format of the data, meaning the order in which they are
presented
b. the type of data which is processed.
c. the quantity of data which is processed.
d. None of the above
9. Which of the following best describe the term "Timing"?
a. How fast data should be sent.
b.When data should be sent.
c. Both of the above.
d. None of the above
10. Which of the following best describes the term "Semantic"?
a. How a particular pattern to be interpreted.
b. What action is to be taken based on that interpretation?
c. Both of the above.
d. None of the above
Exercise 6 Protocols
Student Practical Handbook Comp277/L
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11. Which of the following best describes the term "Connection-Oriented protocols"?
a. In connection-oriented services, a path is established between the two
communicating parties after the data have been exchanged.
b.In connection-oriented services, a path is established between the two
communicating parties before any data is exchanged.
c. Both of the above.
d. None of the above
12. Which of the following best describes the main characteristic of most Connection-
Oriented protocols?
a. They guarantee delivery
b. They do not guarantee delivery
c. They provide delivery only in some circumstances
d. All of the above.
13. Which of the following best describes the main characteristic of Connectionless
protocols?
a. They guarantee delivery
b. They do not guarantee delivery
c. They always provide delivery
d. All of the above.
14. Which of the following best describes a routable protocol?
a. a hazardous communication path can be set up between two
workstations
b. a successful communication path can be set up between two
workstations
c. All of the above.
d. None of the above
15. Which of the following best describes a non-routable protocol?
a. a successful communication path cannot be set up between two
workstations
b. a successful communication path can be set up between two
workstations
c. a successful communication path can be always set up between two
workstations
d. None of the above
Exercise 6 Protocols
Student Practical Handbook Comp277/L
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2. For each description in the following table, write the appropriate protocol type
(connection-oriented, connectionless, routable, and non-routable
Protocol Type Description
In this protocol, a successful communication path can be set up (either a virtual
connection-oriented circuit or a data path for datagram communication) between
two workstations, no matter what network hardware lies between them. For
example, machine A is on a separate network from machine B. A router linking the
two networks separates the two machines. The protocol realizes that machine B is
not on the same network as machine A; therefore, this protocol directs the data to
the router, which decides how to best forward it so that it reaches machine B.
This protocol makes no guarantees that the recipient is listening. Its service is
similar to the postal service: the sender addresses a letter to a particular person and
puts it in the mail. The sender doesn't know if the recipient is expecting to receive a
letter or if severe storms are preventing the post office from delivering the message.
This protocol is not able to make provisions to set up a successful communication
path between two workstations; the router drops any packets of this protocol that it
receives. The router does not forward a packet from this protocol even if the
packet's intended destination is on the connected subnet.
In this service, a path is established between the two communicating parties before
any data is exchanged. This ensures that there is a route between the two parties in
addition to ensuring that both parties are alive and responding. In addition, most of
these protocol types guarantee delivery, which increases overhead as additional
computations are performed to verify correctness.
3. For each protocol in the following table, check "" the appropriate
characteristic. (1 marks)
Connection-
oriented Connectionless Reliable Unreliable Fast Slow
TCP
IP
Answer Sheet Topics: 2, 3 and 4
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Assignment 1 - Answer Sheet
Student Name:
Questions Topic 2 Topic 3 Topic 4
a b c d a b c d a b c d 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40.
Answer Sheet Topics: 5 and 6
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Assignment 2 - Answer Sheet
Student Name:
Questions Topic 5 Topic 6
a b c d a b c d 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.