Lesson Plan
Course Title: Telecommunications and Networking
Session Title: Topologies and Access Methods
Lesson Duration:
This lesson will take approximately 150 minutes (2.5 hours)
[Lesson length is subjective and will vary from instructor to instructor]
Performance Objective:
Upon completion of this assignment, the student will be able to describe and design the major
topologies used in computer networking.
Specific Objectives:
 Differentiate between a logical topology and a physical topology
 Describe and design a bus network
 Describe and design a ring network
 Describe and design a star network
 Describe and design a mesh network
Preparation
TEKS Correlations: 130.274
(4) The student acquires an understanding of telecommunication and data network services
(K) differentiate between local area networks and wide area networks
(5) The student analyzes various types of configurations and upgrading
(E) recognize the differences among computer network topologies
(6) The student recognizes and recommends the various types of network components to
address industry needs
(A) analyze various types and components of networks
(B) analyze the characteristics of networks used to select the optimum configuration for
an industry solution
Instructor/Trainer
The instructor must have a strong knowledge of network topologies and terminology including
the type of cabling, connectors, and scenarios for the following network types:
 Bus
 Ring
 Star
 Mesh
References:
Conduct an online search for information on network topologies
Conduct an online search for network tutorials
Instructional Aids:
IT: Telecommunications and Networking: Topologies Lesson Plan
Copyright © Texas Education Agency, 2013. All rights reserved.
1
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Topologies Presentation
Topologies Handout 1
Topologies Handout 2
Topologies Quiz
Materials Needed:
Paper (for printed assignments)
Equipment Needed:
 Computer that can be used by instructor to demonstrate how to use the application for
creating interactive network diagrams (Handout 1)
 Computers with an application for creating interactive network diagrams installed for
students to use
Learner
Students must understand these basic networking terms and concepts:
1. Network
a. LAN
b. MAN
c. WAN
2. Networking Media (Twisted pair [TP], Untwisted Pair [UTP], Fiber Optics)
3. Traffic
4. Fault-tolerance
5. Workstation/Node
6. Hub
7. Switch
8. Central Device
Introduction
MI
Introduction (LSI Quadrant I):
Greet students as per your routine. Lead into the discussion by asking students how
they hear about breaking news, whether it is world news or what is going on in the
lives of their friends. Ask them to think about how information travels around the
school/their group of friends: is it organized like a straight line (first person tells the
second, second person tells third etc.)? A circle (first person is retold by last
person)? Is it random and moves around like how the strings in a fishing net are
connected?
Ask someone in the class to draw on the board a diagram of how (s)he thinks
information travels through his/her group of friends (or school). Based on the
drawing, explain how this would be a ‘logical’ or theoretical map of how information
travels.
Now, arrange several students in a ring holding hands. Draw on the board a ‘map’ of
how the students are arranged. Explain that the diagram you drew represents a true
physical representation of how the students are arranged, much like a map of a
state/city/etc.
IT: Telecommunications and Networking: Topologies Lesson Plan
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Explain that just like the exercises you just demonstrated the same things are done
in the world of networking. We call these layouts the ‘network topology’ and that
there are logical topologies and physical topologies. Explain that the logical and
physical topologies do not always look the same. Tell the students that they will be
studying physical network topologies and learn under what circumstances each
topology should be used.
Outline
MI
Outline (LSI Quadrant II):
Instructor Notes:
Defining topology:
Define a node as any device
attached to the network that
is capable of processing and
forwarding data.
The physical arrangement of devices on a network is
the ‘network topology’. It literally refers to how and
where equipment is connected to the network.
Define a backbone as a
cable that serves as a
common path and often
employs high-speed network
cable such as fiber-optic
There are four major topologies:
Bus
Star
Ring
Mesh
The first network to be discussed is the simplest and
most inexpensive to build but the easiest to break:
Bus
Explain that sometimes the
network topology is a hybrid
(it is formed by combining
one or more of the major
network topologies)
Uses a single cable to
connect all the devices to
each other and often serves
as a backbone to link other
topologies
On slide 4: Regarding
missing terminator: signal
bounce occurs when the
signal/packet simply travels
endlessly between the two
ends of the network. No new
signals can get through
Slide 5:
Under Cons, point this out:
Not Scalable: When you add
nodes, you decrease network
performance because the
nodes share bandwidth
Difficult to troubleshoot:
Single point of failure means
if the cable is damaged or
broken in one place, none of
IT: Telecommunications and Networking: Topologies Lesson Plan
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the nodes can transmit data
Second network to discuss is Ring:
Ring is slightly more expensive than bus
Repeater is a device that
regenerates a signal
Active topology: all
workstations participate in
delivery of data
TP: Twisted pair
Token passing:
Ring networks function
through token passing.
Tokens are 3-byte packets or
‘control frames’.
Think of a clock face. If the
12 o’clock computer wants to
send a message to the 11
o’clock computer, it must
send the data all the way
around with each ‘hour’
checking to see if the
message is intended for
them. When each ‘hour’
determines that the data is
not for it, it forwards the
signal to the next computer in
line.
In token passing, the token
travels the ring until it gets a
signal from a computer
stating, “I need to send data”.
When the token passes that
computer again, the data is
attached to the end of the
‘empty’ token and sent to the
next computer in line and so
on until the correct node
receives the data. The
receiving computer attaches
an acknowledgement or
ACK, which is a verification
of receipt to the token, and
puts it back on the network.
The token returns (still
traveling clockwise) to the
sending computer. The
IT: Telecommunications and Networking: Topologies Lesson Plan
Copyright © Texas Education Agency, 2013. All rights reserved.
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sending computer then puts
the now ‘empty’ token back
on the network for use by
another node.
The third topology is the Star. Star provides for
centralized management of the network with a
centralized device in the form of a hub or switch.
Tell students that in order to
keep networks manageable,
they need to divide them into
sub-nets (sub-networks) that
are connected to each other
by switches/bridges/routers
Last topology is the Mesh
The Mesh requires an
extensive amount of cabling
and usually no centralized
management
High fault tolerance is due to
the fact that if one cable
breaks between nodes, there
is another route for the data
to take to get to the node
Adding a device requires
connecting the device to
every other device on the
network, which is why
scalability is more difficult
than with star network
Application
MI
Guided Practice (LSI Quadrant III):
Give students Interactive Network Diagrams Handout 1:
The instructor will demonstrate how to use the application for the class.
Connect a computer with the application installed to an overhead projector.
Students should have access to a computer on which they can work along with
the instructor and create a map of a small bus network (four computers) with
each computer labeled as Node 1, Node 2, etc...
MI
Independent Practice (LSI Quadrant III):
Give students Interactive Network Diagrams Assignment (Handout 2). They should
complete this portion of the assignment individually. Students should print the
topologies they design and submit for review to the instructor. There should be some
IT: Telecommunications and Networking: Topologies Lesson Plan
Copyright © Texas Education Agency, 2013. All rights reserved.
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leeway given for the design process; however, they must include all components
required.
Summary
MI
Review (LSI Quadrants I and IV):
Have students develop a list of questions based on the presentation. Collect the
questions and review them for appropriateness. Divide the students into pairs and
redistribute the questions (making sure no student gets their questions to answer).
Have the students answer the questions and then review them as a class.
Evaluation
MI
Informal Assessment (LSI Quadrant III):
The instructor will monitor student progress during the independent practice portion
of the lesson and ensure that the students understand how to use the application
and the concepts of the different topologies. The teacher will use this time to
reteach/redirect as needed.
MI
Formal Assessment (LSI Quadrant III, IV):
Students will take a quiz to ensure mastery of the material.
IT: Telecommunications and Networking: Topologies Lesson Plan
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Interactive Network Diagrams
Handout 1
1. Find the shortcut for the application and open the program.
2. Note that when the program opens, it may not have the grid lines; let’s go ahead and
have the grid lines visible for ease of design.
a. Look at the top of the program window and click on: Options > Grid Lines
i. You should now see the grid lines
3.
Hover the mouse pointer over the black and blue button under ‘Format’. This is the
Object Libraries link. Click on the Object Libraries button and a new window opens.
4. The new window should auto open to the ‘General’ library. It will have everything you
need to complete this set of lessons.
a. Notice that all the icons represent basic networking equipment.
i. Routers
ii. Servers
iii. PCs
iv. Printers
5. In this exercise, we are going to create a 4-node bus topology.
a. In the Object Libraries window, click on the Pc1 icon
b. Now click on the button that looks like an upside-down top hat (it is the ‘hide’
button).
i. It will send the Object Libraries window to the background
c. Now you should be back at the graph pad looking at a box drawn with a dotted
line and a cross in the middle of it.
d. Pick a place somewhere near the top left corner of the grid and left click with your
mouse in order to place your first PC node.
i. Note: The selection does not reset. Every time you click, it will place a PC
node wherever you click until you change the instruction.
e. Now, right click on your PC1 and choose Properties
f.
In the box Object Name, rename PC1 to Node 1 and click OK
i. Note that on the grid, the component is now renamed Node 1
g. Repeat steps a – f, renaming each node with the correct number until you have
four nodes.
IT: Telecommunications and Networking: Topologies Lesson Plan
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h. Now we need to connect the nodes together. We do this by clicking on the link
button and choosing the media we want to use to connect our network. In this
case, click on the link button; in the drop down box next to it, choose 100baseT
as your connection media.
i.
Now your pointer should look like an upward pointing arrow. Click on Node 1 and
then click on Node 2. A straight grey line should now connect the first two nodes.
j.
Repeat step i until all the nodes are connected.
Congratulations! You have diagramed a 4-Node Bus topology. Like all buses, it has a single
cable connecting the nodes, and it consists of less than 10 computers/nodes. You can save the
sketch as a Network Notepad file or export it to a bitmap file. You also have the option of
printing the file; however, make sure that if you choose to print the file, you select the option to
‘Scale to Paper Size’ in printer options before you print.
Spend some time getting familiar with the application so that you can complete the next
assignment on your own.
IT: Telecommunications and Networking: Topologies Lesson Plan
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Interactive Network Diagrams
Handout 2
Independent Practice
In this assignment, you will create the following network topologies in the application and print
the assignment for a grade. Each node should have a unique name (i.e. Node 1A, Node 1B,
Node 2A, Node 2B, etc. with the number denoting which question the network correlates to).
1. Bus network with the following components:
a. 9 PC nodes
b. Connected by 10baseT media
2. Ring network with the following components:
a. 8 PC nodes
b. Connected by 100baseT media
3. Star network with the following components:
a. 2 servers
b. 8 PC nodes
c. 2 print devices
d. Connected by 100baseT media
4. Mesh network with the following components:
a. 1 router
b. 11 PC nodes
c. 5 print devices
d. Connected by fiber optic media
IT: Telecommunications and Networking: Topologies Lesson Plan
Copyright © Texas Education Agency, 2013. All rights reserved.
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Interactive Network Diagrams
Handout 2
Independent Practice
Grading Key/Guide
For this exercise, the students should have a fair amount of freedom to design their networks.
The primary shapes should be as follows:
Bus
Ring
Star
Mesh
Deductions are as follows:
Missed node/print device = - 1 point
Incorrect media type = - 2 points
Unlabeled nodes = - 1 point
IT: Telecommunications and Networking: Topologies Lesson Plan
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Name:
Network Topologies Quiz
1. On a bus network, each computer transmits the packet to the next computer in line. The
receiving computer removes the packet from the bus.
True or False
2. On a ring network, a packet is transmitted to each computer in the ring in counterclockwise order.
True or False
For each of the following questions, what network topology is most appropriate? Choose
from bus, star, ring, and mesh.
3. A small real estate office has four computers that need to share a printer.
4. A bank has four locations in one town. All branches must link to each other and to a
central office.
5. A school district has eight campuses and wants to connect all of them to the
administrative offices downtown but not to each other.
For each of the following questions, draw the appropriate network topology and answer
the question regarding the transmission of packets.
6. Draw a bus network with four nodes. Label each node A, B, C, and D.
7. In the above diagram, if Node B is transmitting to Node C, circle the nodes that will
receive the transmitted packets.
8. Draw a star network with four nodes attached. Label the nodes A, B, C, and D.
9. If Node A is transmitting packets to Node D, circle the nodes that will receive the
transmitted packets.
10. Which topology requires the least cable? Which topology is the most fault-tolerant?
IT: Telecommunications and Networking: Topologies Lesson Plan
Copyright © Texas Education Agency, 2013. All rights reserved.
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Name: KEY
Network Topologies Quiz
1. On a bus network, each computer transmits the packet to the next computer in line. The
receiving computer removes the packet from the bus.
True or False
2. On a ring network, a packet is transmitted to each computer in the ring in counterclockwise order.
True or False
For each of the following questions, what network topology is most appropriate? Choose
from bus, star, ring, and mesh.
3. A small real estate office has four computers that need to share a printer.
Ring
4. A bank has four locations in one town. All branches must link to each other and to a
central office.
Mesh
5. A school district has eight campuses and wants to connect all of them to the
administrative offices downtown but not to each other.
Star
For each of the following questions, draw the appropriate network topology and answer
the question regarding the transmission of packets.
6. Draw a bus network with four nodes. Label each node A, B, C, and D.
A
B
C
D
7. In the above diagram, if Node B is transmitting to Node C, circle the nodes that will
receive the transmitted packets.
See circles drawn in question 6.
8. Draw a star network with four nodes attached. Label the nodes A, B, C, and D.
A
C
B
D
9. If Node A is transmitting packets to Node D, circle the nodes that will receive the
transmitted packets.
See circles drawn in question 8.
IT: Telecommunications and Networking: Topologies Lesson Plan
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10. Which topology requires the least cable? Which topology is the most fault-tolerant?
Least cable is bus topology. Most fault-tolerant is mesh.
IT: Telecommunications and Networking: Topologies Lesson Plan
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