Higher Nationals
Internal verification of assessment decisions – BTEC (RQF)
INTERNAL VERIFICATION – ASSESSMENT DECISIONS
HND in Computing
Programme title
Assessor
Unit(s)
Assignment title
Internal
Verifier
Unit 02:
Networking
LAN Design & Implementation for VIDCO
Student’s name
Pas
s
List which assessment
criteria the Assessor has
awarded.
Merit
Distinction
INTERNAL VERIFIER CHECKLIST
Do the assessment criteria awarded
match those shown in the
assignment brief?
Y/N
Is the Pass/Merit/Distinction grade
awarded
justified by the assessor’s comments on
the
student work?
Has the work been
assessed accurately?
Y/N
Y/N
Is the feedback to the student:
Give details:
• Constructive?
• Linked to relevant assessment criteria?
• Identifying opportunities
for improved
performance?
• Agreeing actions?
Y/
N
Y/
N
Y/
N
Y/N
Does the assessment decision
need amending?
Y/N
Assessor signature
Date
Internal Verifier signature
Date
Programme Leader signature (if required)
Date
Confirm action
completed
Remedial action taken
Give details:
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Unit 02
Assessor signature
Date
Internal Verifier
signature
Date
Programme
Leader signature
(if required)
Date
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Unit 02
Higher Nationals - Summative Assignment Feedback Form
Student Name/ID
Unit Title
Unit 02:
Assignment
Number
1
Networking
Assessor
Date
Received 1st
submission
Submission Date
Date Received
2nd submission
Re-submission Date
Assessor Feedback:
LO1 Examine networking principles and their
protocols.
P
Pass, Merit & Distinction
2
P
1
M1
LO2 Explain networking devices and
operations.
Pass, Merit & Distinction
P
3 Descripts
P4
LO3 Design efficient networked
systems.
P6
Pass, Merit & Distinction
LO4 Implement and diagnose
networked
P
systems.
5 Descripts
P
Pass,
Merit & Distinction
8
P
7
Grade:
M2
D1
M3
D2
M4
D
3
Assessor Signature:
Date:
Resubmission Feedback:
Grade:
Assessor Signature:
Date:
Internal Verifier’s Comments:
Signature & Date:
* Please note that grade decisions are provisional. They are only confirmed once internal and external moderation has
taken place and grades decisions have been agreed at the assessment board.
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Assignment Feedback
Formative Feedback: Assessor to Student
Action Plan
Summative feedback
Feedback: Student to Assessor
Assess
or
signatur
e
Date
Student
signatur
e
Date
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Unit 02
Pearson Higher Nationals in
Computing
Unit 02: Networking
Assignment 01
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General Guidelines
1. A Cover page or title page – You should always attach a title page to your assignment. Use
previous page as your cover sheet and make sure all the details are accurately filled.
2. Attach this brief as the first section of your assignment.
3. All the assignments should be prepared using a word processing software.
4. All the assignments should be printed on A4 sized papers. Use single side printing.
5. Allow 1” for top, bottom , right margins and 1.25” for the left margin of each page.
Word Processing Rules
1.
2.
3.
4.
The font size should be 12 point, and should be in the style of Time New Roman.
Use 1.5 line spacing. Left justify all paragraphs.
Ensure that all the headings are consistent in terms of the font size and font style.
Use footer function in the word processor to insert Your Name, Subject,
Assignment No, and Page Number on each page. This is useful if individual sheets
become detached for any reason.
5. Use word processing application spell check and grammar check function to help editing
your assignment.
Important Points:
1. It is strictly prohibited to use textboxes to add texts in the assignments, except for the
compulsory information. eg: Figures, tables of comparison etc. Adding text boxes in the
body except for the before mentioned compulsory information will result in rejection of your
work.
2. Carefully check the hand in date and the instructions given in the assignment. Late
submissions will not be accepted.
3. Ensure that you give yourself enough time to complete the assignment by the due date.
4. Excuses of any nature will not be accepted for failure to hand in the work on time.
5. You must take responsibility for managing your own time effectively.
6. If you are unable to hand in your assignment on time and have valid reasons such as
illness, you may apply (in writing) for an extension.
7. Failure to achieve at least PASS criteria will result in a REFERRAL grade .
8. Non-submission of work without valid reasons will lead to an automatic RE FERRAL. You
will then be asked to complete an alternative assignment.
9. If you use other people’s work or ideas in your assignment, reference them properly using
HARVARD referencing system to avoid plagiarism. You have to provide both in-text
citation and a reference list.
10. If you are proven to be guilty of plagiarism or any academic misconduct, your grade
could be reduced to A REFERRAL or at worst you could be expelled from the course
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Student Declaration
I hereby, declare that I know what plagiarism entails, namely to use another’s work and to
present it as my own without attributing the sources in the correct form. I further understand what
it means to copy another’s work.
1. I know that plagiarism is a punishable offence because it constitutes theft.
2. I understand the plagiarism and copying policy of Edexcel UK.
3. I know what the consequences will be if I plagiarise or copy another’s work in any of the
assignments for this program.
4. I declare therefore that all work presented by me for every aspect of my program, will be my own,
and where I have made use of another’s work, I will attribute the source in the correct way.
5. I acknowledge that the attachment of this document signed or not, constitutes a binding
agreement between myself and Pearson, UK.
6. I understand that my assignment will not be considered as submitted if this document is
not attached to the assignment.
Student’s Signature:
(Provide E-mail ID)
Date:
(Provide Submission Date)
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Higher National Diploma in Computing
Assignment Brief
Student Name /ID Number
Unit Number and Title
Unit 2: Networking
Academic Year
201
2020/21
Unit Tutor
Assignment Title
LAN Design & Implementation for VIDCO -19
Issue Date
Submission Date
IV Name & Date
Submission format
The submission should be in the form of an individual reportwritten in a concise, formal business style
using single spacing and font size 12. You are required to make use of headings, paragraphs and
subsections as appropriate, and all work must be supported with research and referenced using Harvard
referencing system. Please also provide an end list of references using the Harvard referencing system.
The recommended word count is 3,000–3,500 words for the report excluding annexures,
although you will not be penalised for exceeding the total word limit.
Unit Learning Outcomes:
LO1 Examine networking principles and their protocols.
LO2 Explain networking devices and operations.
LO3 Design efficient networked systems.
LO4 Implement and diagnose networked systems.
Assignment Brief and Guidance:
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Case Study
VIDCO-19 is a privately owned, well-known Software company located in Colombo. The Management
of VIDCO-19 has purchased a 3 story building in the heart of Kandy. They are planning to make it one
of the state-of-the-art companies in Kandy with the latest facilities.
It is expected to have nearly 150 employees in Kandy branch.
Department
Number of Users
Customer Care
10
Sales and Marketing
20
Finance
25
Legal
5
HR
10
Developers
55
Network Team
5
Server Room
Servers +ISP connections
Following requirements are given by the Management;

All the departments must be separated with unique subnet and should not
communicate with each other unless there is a special requirement.

192 . 168 . 10. 0 /24 is given and should be used for all the departments except
the server room. IPs should assign using DHCP.

ERP and CRM Systems need to be implemented in Kandy branch in local
servers.

Number of servers required for the Server room need to be decided by the
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Network designer and should be assigned with 10. 254. 1. 0/24 subnet. ( Uses static IPs)

High level of redundancy is expected in network design to eliminate single
point of failures and traffic bottle necks.

Sales and Marketing Team need to access Network resources using WIFI
connectivity.

Proper methods for networking monitoring and troubleshooting need to be
established.

All possible network security mechanisms should be implemented.
Assume you have been appointed as the new network consultant of VIDCO - 19 Solutions. Prepare a
network architectura l design and implement it with your suggestions and recommendations to meet
the company requirements.
( Note: Clearly state your assumptions. You are allowed to design the network according to your
assumptions, but main requirements should not be violated)
Task 01
1.1
Discuss the different network models/ system types that can be implemented in
Kandy branch with their benefits and constraints.
1.2
Discuss main IEEE Ethernet standards that can be used in above LAN and
WLAN design?
1.3
Critically analyze network protocol suites
used in Network Industry and
recommend suitable network protocol suites for above scenario and justify your
selection.
1.4
Explain the difference between Logical topology and Physical topology using
examples and compare main network topologies used in network design.
1.5
Recommend a suitable network topology for above scenario and justify your
answer with valid points.
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Task 02
2.1
Discuss the operating principles of network devices that can be used for above
scenario.
Ex: Router, Switch, Etc.
2.2
Explore and describe the devices which we can use to enhance security of
VIDCO- 19 Kandy Branch.
2.3
Critically analyze the importance of networking software and provide
Examples for networking software can be used in above network design.
2.4
Discuss the importance of Servers in computer networks and research on
Servers that are available in today’s market with their specifications a n d
Recommend server/ servers and workstations for above scenario and justify your selection
with valid points.
2.5
Discuss why it is important to have compatible devices and related software in
network design.
Task 03
3.1
1 Provide VLAN and IP subletting scheme for above scenario to satisfy user
requirements.
3.2
2 Provide a list of devices, network components and software need to design a
network for above scenario and justify your selection.
3.3
3 Provide a detailed network design (Diagram) for your design using modeling
tool. (Ex: Microsoft Visio).
3.4
4 Design a User feedback form and get feedback from network users and analyze
their feedback and suggestions.
3.5
5
Install and configure Network services and Applications* of your choice to
accomplish above user requirements. (Ex: DHCP, DNS, Active Directory, Proxy,
Web, Etc.)
(Note: Screen shots of minimum 2 services are required)
3.6
6 Design a detailed Maintenance schedule for above Network design.
* Note: - Screen shots of Configuration scripts should be presented.
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Task 04
4.1
1 Implement and configure all network devices* according to the requirements
given in the scenario.
4.2
Develop test cases and Test the above Network to verify * whether the design
objectives are met.
4.3
Discuss why network monitoring is important in VIDCO- 19 Kandy branch?
Explain with valid points.
4.4
Install and configure Network monitori ng tool/tools* of your choice and
analyze results.
4.5
Provide troubleshooting steps for following situations;
a. Everything is working normally but suddenly the connection goes
away, and then comes back, and then goes away again on client
Computer. (I. e., flapping)
b. Network cable plugged in, but getting no connection.
4.6
Recommend potential future enhancements for the networked system and
justify your recommendations.
4.7
7
Write a conclusion for your report by critically evaluating design,
planning, Configuration and testing of your network.
* Note: - Screen shots of Configuration scripts should be presented.
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Grading Rubric
Grading Criteria
Achieved
Feedback
LO1 : Examine networking principles and their
protocols.
P1
Discuss the benefits and constraints of different network
types and standards.
P2
Explain the impact of network topology, communication
and bandwidth requirements.
M1
Compare common networking principles and how
protocols enable the effectiveness of networked systems.
LO2 : Explain networking devices and operations
P3
Discuss the operating principles of networking devices and
server types.
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P4
Discuss the inter-dependence of workstation hardware
with relevant networking software.
M2
Explore a range of server types and justify the selection of
a server, considering a given scenario regarding cost and
performance optimization.
LO 1 & LO2
D1
Considering a given scenario, identify the topology
protocol selected for the efficient utilisation of a networking
system.
LO3 : Design efficient networked systems
P5
Design a networked system to meet a given specification.
P6
Test and evaluate the design to meet the requirements
and analyze user feedback.
M3
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Install and configure network services and applications on
your
choice.
D2
Design a maintenance schedule to support the networked
system.
LO4 : Implement and diagnose networked
systems
P7
Implement a networked system based on a prepared
design.
P8
Document and analyze test results against expected
results.
M4
Recommend potential enhancements for the networked
systems.
D3
Use critical reflection to evaluate own work and justify
valid conclusions.
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Acknowledgment
I would like to express my deep gratitude to those who guide me and their valuable
contribution to accomplish this assignment on time.
First I wish to thank my Lecture Mr. Tharindu for his great support, perfect guidance,
valuable supervision, and encouragement in finishing this assignment.
Last but not least, I would like to thank my all the classmates of my Batch 26 who helped me
always and special thank for my parents for their unlimited support.
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Task 01
1.1
A network model is a design or architecture to manage communication between different
network systems. As well as network models can define as network stacks or protocol
suits.
Mainly there are two network models,
OSI Model
TCP/IP Model
Normally network model consists of layers. Those layers include specific functions.
Computer network models are responsible for establishing a connection between the
sender and receiver and transfer the data smoothly.
The OSI Model
OSI stands for Open System Interconnection and creates by International Organization
for Standardization in 1984. The OSI model is the general-purpose networking model or
communication model. Moreover, when we are using the OSI model, any connection can
establish until any protocols are not used as the OSI model does not support protocol
establishment.
There are seven layers in the OSI model.
Figure 1: OSI Model
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Physical Layer
This layer deals with the physical transmission medium itself. It has include
specifications such as voltages, pin layout, cabling, and radio frequencies. Essentially
this layer puts the data on the physical media as bits and receives it in the same way.
Data Link Layer
It verifies the data must be synchronized, error detection and enable the control. It has
two sub layers.
MAC (Media Access Control) – Flow control
LLC (Logical Link Control) – Flow and error control/ Identifies the line protocols
Network Layer
Mainly responsible for receiving frames from the data link layer. And also deliver them
to destinations by using their address. In this layer Router is the most important
component to get packets from one network to another.
Transport Layer
This layer is responsible for delivery of data and checking errors of packets.
Session Layer
This layer Controls the conversations between different computers. Session layer
designed for mainframe and terminal communications.
Presentation Layer
This layer is responsible for data formatting. Presentation layer can also handle the
encryption and decryption required by the application layer.
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Application Layer
End user and the application layer directly interact with the software applications. Web
browsing, file transfer, messaging are in this layer. This layer identifies resource
availability, communication partners and synchronizes communication.
Advantages of OSI Model

Each layer has specific structure and functionality, therefore it is easy to use.

Support for connection oriented and connection less services.

As this model general purpose reference model, can use for data communication.

Possible to connect with any type of devices, host, hardware or software.
Disadvantages of OSI Model

Due to inability to fit protocols, this model replaced by TCP/IP Internet Model.

Because of the theoretical model and it restricts practical implementation

Due to complex model, its initial implementation is slow
TCP/IP Model
This model developed before OSI model. TCP/IP model has four layers.
Figure 2: TCP/IP Model
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Network Access Layer – It handles the physical parts of sending and receiving data
using the wireless network, Ethernet cable, Network Interface Card etc.
Internet Layer - This layer responsible for travel to packet independently to the
destination.
Transport Layer – Transport layer provides good connection between two devices.
Application Layer – Described a lot of applications. Some of them were TELNET,
SMTP, DNS, DHCP, FTP
Advantages of TCP/IP Model

Use for flow control, Error control

Congestion Control

Provide a unique IP address for each computer on the network and it can identify
over the network.
Disadvantages of TCP/IP Model

TCP connection is not designed for small networks like, LAN and PAN. Design
only for Wide Area Networks.

Loss result of congestion

It can be slower at the beginning.
When we implement a network to communicate different devices through the network that
we choose either the OSI or the TCP/IP model. But both model has advantages and
disadvantages as well. When one model is good for one case, on the other hand worst for
another case.
If focus on proper documentation, specification and modularization, it’s better to choose OSI
model. But we focus on implementation, reliability and security, it’s better to select TCP/IP
model.
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Network System Types
A computer network is a collection of computer devices that are connected together to
communicate with another computer and share resources or data.
A computer network can categorize by their size.

LAN (Local Area Network)

PAN (Personal Area Network)

MAN (Metropolitan Area Network)

WAN (Wide Area Network)

WLAN (Wireless Local Area Network)
Figure 3: Types of computer network
LAN - Local Area Network
LAN is designed for small geographical area such as office, factory or buildings. It is used to
connect two or more computers through a communication medium such as twisted pair,
coaxial cable. We can use different types of topologies through LAN such as Star, BUS,
Ring, Tree etc. In Local Area Network data transferred at an extremely faster. As well as
LAN provides higher security.
Figure 4: Local Area Network
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PAN – Personal Area Network
Personal Area Network is a computer network that connect devices within the range of an
individual person. Personal Area Network covers area of 30 feet. It’s typically involves a
computer, phone, printer, tablet, speakers and video game consoles etc. Thomas Zimmerman
was the first research scientist regarding personal area network.
Figure 5: Personal Area Network
MAN – Metropolitan Area Network
Metropolitan Area Network is the large computer network that covers large geographical area
which includes several buildings or even the entire city. MAN is larger than LAN but smaller
than WAN. The most commonly used protocols in MAN are RS-232, Frame Relay, ATM,
ISDN, OC-3 and ADSL.
Figure 6: Metropolitan Area Network
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WAN – Wide Area Network
Wide Area Network is used for the network that covers large distance such as states or
countries. WAN can lease private network or public network. The Internet is the biggest
WAN in the world. This network commonly uses for Business field, education and
government.
Figure 7: Wide Area Network
WLAN – Wireless Local Area Network
WLAN that connects two or more devices using a wireless distribution method and it
provides access to the public Internet. WLAN is the implemented as an extension to a wired
LAN within a building or campus. Wireless LAN is commercially known as WIFI.
Figure 8: Wireless Local Area Network
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1.2 Network Standards
What is IEEE Ethernet Standards?
Ethernet is a set of technologies and protocols that are used primarily in LANs. It was first
standardized in 1980s by IEEE 802.3 standard. IEEE 802.3 defines the physical layer and the
medium access control (MAC) sub-layer of the data link layer for wired Ethernet networks.
Ethernet is classified into two categories: classic Ethernet and switched Ethernet. (John,
2019)
Organizations

ITU (International Telecommunication Union)

ANSI (American National Standards Institute)

ISO (International Standards Organization)

IEEE (Institute of Electrical and Electronic Engineers)
Data Link layer contains two sub layers.

Logical Link Control (LLC)

Media Access Control (MAC)
The IEEE 802 standard cowl the physical layer terms of technologies from LAN to wireless.
802
LAN /MAN
802.1
Standard related to network management
802.2
Standard for the data link layer (DLL) in the OSI reference model
802.3
Ethernet standard
802.4
Token Bus network
802.5
Token Ring network
802.7
Broadband Technical advisory group
802.8
Fiber Optic Technical advisory group
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802.9
Integrated voice and data network
802.10
Stands for Interoperable LAN / MAN security.
802.11
Wireless network
802.12
100 mbps technologies including 100 base vg LAN
802.14
Cable modems and Broadband communication
802.15
Wireless Personal Area Networks such as Bluetooth.
802.16
Wireless Metropolitan Area Networks
802.12
100 mbps technologies including 100 base vg LAN
802.14
Cable modems and Broadband communication
802.15
Wireless Personal Area Networks such as Bluetooth.
802.16
Wireless Metropolitan Area Networks
Table 1: IEEE Standard 802
1.3 Network Protocol
All the rules and agreements are included in a network protocol to communicate between
network devices, including ways devices can identify and make connections with each
other. As well as there are formatting rules that how data is packaged into sent and received
messages.
If not protocols devices wouldn’t ability to understand the electronic signals over the
network connection. Generally modern protocols use packet switching techniques to send
and receive messages in the form of packets. Those messages subdivide to pieces that are
collected and reassembled at their destination. There are so many computer network
protocols have been developed and each designed for specific purposes.
Protocol
Acronym
File Transfer Protocol
FTP
Secure Shell Protocol
SSH
Simple Mail Transfer Protocol
SMTP
Hyper Text Transfer Protocol
HTTP
Post Office Protocol
POP 3
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Telnet
Network File Services
NTFS
Domain Name service
DNS
Dynamic Host Configuration Protocol
DHCP
Simple Network Manage Protocol
SNMP
Transmission Control Protocol
TCP
User Datagram Protocol
UDP
Internet Control Message Protocol
ICMP
Address Resolution Protocol& The Reverse
Address Resolution Protocol
ARP&RARP
Internet Protocol
IP
Table 2: Network Protocol Types
I think Internet Protocol is most suitable for the above scenario.
1.4 Network Topology
What are the Network Topologies?
Network topology describes the arrangement of the elements of a communication network.
It defines how the computers or nodes within the network are arranged and connected to
each other. The way in which a network of computers is connected. It defines the
arrangement of nodes, cable, and connectivity devices that make up the network.
Types of Network Topology
Figure 9: Types of Network Topology
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Physical Topology
Describes the actual layout of the network transmission media. It describes the way of a
computer connects with the help of cables.
Types of Physical Topology

Star Topology
A computer or a server or switch is used here in the middle to connect all the computers to
one another. It is the most common type used. All computers are attached to a Hub.
Figure 10: Star Topology

Bus Topology
This computer network is built centering on the main wire and connecting all the computers
and other devices to it. Bus topology allows information to be directed from one computer
to another.
Figure 11: Bus Topology

Ring Topology
Here computers are positioned in a ring/bangle and connected through cables. Data or
information move in a circular manner. The breakdown of one computer or cable can lead
to the breakdown of the entire network.
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Figure 12: Ring Topology

Mesh Topology
In this topology, all the network nodes are connected individually to most of the other nodes.
Mesh topology is not a commonly used network topology. Here, normally there is not a
concept of a central switch, computer, or hub that acts as a central point of communication to
pass on the messages.
It can divide into two categories.
 Fully connected mesh topology
 Partially connected mesh topology
Figure 13: Mesh Topology

Tree Topology
Tree topology has characteristics of both bus and star topologies. In this design, several star
topologies are connected to a bus backbone cable. One of the advantages of this is the
ability to control each network individually.
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Figure 14: Tree Topology
Logical Topology
Describes how signal follows as it passes among network modes. It describes the way data
flow from one computer to another within a computer network.
The most common logical topologies are,
 Bus Topology
 Ring Topology
Difference between Physical Topology and Logical Topology
Physical Topology
Represents physical layout of network
Can arrange in Star, Bus, Ring, Mesh and
Tree topologies
This has major impact on cost, scalability
and bandwidth capacity of network based
on selection and availability of devices.
It is actual path relevant for transmission
The layout can change according to the
needs
Physical connection of the network.
Logical Topology
Represents logistics of network relevant
with transmission data
It includes Bus and Ring topologies
This has major impact on speed and
delivery of data packets. It also handles
flow control and ordered delivery of data
packets.
It is a high level representation of data
flow.
There is no intervention and manipulation
involved here.
Data path followed of the network
Table 3: Difference between Physical Topology and Logical Topology
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(yashchuahan, 2020)
1.5 Suitable Network Topology for scenario
When setting up a network, first we have to decide what kind of topology is most suitable
according to the requirements. Each type of topologies has advantages and disadvantages.
But we should choose the topology which includes the best performance and stability for
the network.
In my view, Star Topology is the most suitable network topology for the scenario. Because
each node within the company is connected to one central network device such as a hub, a
switch, or a computer via a cable. The central network is the server, and the other devices
are clients.
If one computer wants to send data to another computer. Then the first computer forwards
the message to the hub. After that, the hub will check the Mac Address of the recipient
computer, then forward the message.
The advantage is using this topology one centralized nature of star network and give a
separate data transfer the devices. But the disadvantage is star topology is running use only
one central hub and if this central hub is fall whole network is down.
Star topology is commonly used in office and home networks these days because star
topology can run backups on the using hub in private folders. When the network is down
users can use the data through the next computer. This network is accessing backup files on
the hub. For this reason, star topology is more privacy than other networks.
Task 02
2.1 Network Devices
Network devices mainly use to transmit and receive the data quickly and securely as well as
to communicate between different hardware. Each network device plays a key role based on
their functionality and also works for different purpose at different segments.
(https://www.elprocus.com, n.d.)
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Network Switch
Network switch is working at the layer in the LAN and similar to a hub, but a switch is
cleverer with comparing a hub. Hub is used for data transferring and switch is used for
forwarding and filtering the data. So switch is the best technique to deal with the data
packets.
As well as packets receive the interface of the switch it automatically filters the packets
calculate and receive. At this moment switch is also manage CAM. CAM stands for
Content Addressable Memory table and that own system to contour and memory. The
network switch always provides higher performance.
Figure 15: Network Switch
Modem
In getting the internet with telephone wires, the modem is used to connect the computers of a
computer network or a personal computer at home to the internet. The modem act as a data
translator. Digital signals sent from the computer is translated to analog signals so that they
can be transmitted via telephone line and the analog signals coming from the telephone line
send to the computer from the internet is translated to digital signals.
This is called ‘Modulation’ and ‘Demodulation’. Hence, MODEM is a combination of these
two words.
There are different types of modems.
 Internal
 External
 Wireless modems
Figure 16: Modem
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Router
A router is a device that connects multiple networks that use similar or different protocols. It
manages that the best route between any two communication networks.
It consists of software and hardware. Routers are used when several networks are connected
together.
Routers operate at the network layer or layer 3 of OSI Model. It is used for routing traffic
from one network to another. These two networks could be private network company to
public network. Router has a traffic police who direct different network traffic to another
different direction.
Figure 17: How Router works
Wireless Router
A wireless router is a device in a wireless local area network that forwarded the packet should
be next network point. There are two types of routers. Those are Wired and Wireless. Usually
wired routers use Internet Service Provider (ISP). But wired routers become out of date and
people need to get online via Ethernet cable.
Wireless router stands for an electronic device that work as a router and it means send data
form via internet cable to device and wireless access point this data can be shared through radio
signals instead of another cable. Wireless router always come with at least four Ethernet ports
for connecting PCs, TVs and other home internet tools.
Figure 18: Wireless Router
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2.2 Network Security Devices
Assurance of network security is one of the most important moments for safe and correct
working of the computer systems and networks. The network security includes assurance of
the limited access to sensitive information, the protection from unauthorized access, risks and
potential security threats, and enhancement of network performance. Moreover always needs
to protect the entry points of network and another important thing is encryption, also strong
passwords, the use of antivirus software and modern advanced network security devices.
(https://www.conceptdraw.com, n.d.)
There are some different networking security tools for VIDCO-19 Kandy Branch to enhance
security.
Firewalls
In network, a system design to protect an intranet from unauthorized access is called
‘firewall’. Firewall can be categorized into two parts.
 Hardware firewalls
Hardware firewall is a physical device similar to a server. When connect to the network in
order to protect from unauthorized access.
 Software firewalls
A software firewall is a piece of software that installed in computer in order to protect it from
unauthorized access.
Techniques used by firewalls
 Proxy server
 Application level filtering
 Packet level filtering
 Circuit level filtering
Figure 19: Firewall
Proxy Server
Proxy server provide a valuable security for computer and can be set up as web filter. As well
as protect from internet threats like malware. Also save bandwidth by caching files or
compressing incoming traffic and balance internet traffic to prevent crashes. In addition,
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allows company to block forbidden web sites.
Figure 20: Proxy Server
Network Access Control (NAC)
NAC is a network security control device that restricts the availability of network resources
to endpoint devices that comply with your security policy. Some NAC solutions can be
automatically fixed non-compliant devices to verify whether they are secure before allowing
them to access the network.
Network access control device is responsible to enhance the endpoint security of network.
NAC can use agents to assess the device’s security or it can be agentless. (Melnick, 2019)
Figure 21: Network Access Control
Antivirus
Especially in organization Antivirus software is one of the best security tools. Antivirus can
be a part of endpoint protection systems. That provides not only virus protection but DLP,
AppLocker, content filtering and other capabilities as well.
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Figure 22: Antivirus
2.3 Networking Software
What is a Network Software?
Network software enclosed a broad range of software used for design, implementation and
operation as well as monitoring of computer networks. Traditional networks means hardware
based with software embedded.
Software Defined Networking (SDN) separated from the hardware thus making it more
adaptable to the ever-changing nature of the computer.
There are lot of computing architectures for SDN from different providers. A high-level view
of the architecture in simple terms centralizes control of the network by separating the control
logic to off-device computer resources. All architectures have a form of an SDN controller,
southbound APIs, and northbound APIs and controllers are the brain of the network. Through
the APIs relay information between the controller, switches, routers and applications.
Importance of Networking Software
Network software is not the same as software applications. Especially software applications
allow end users to perform specific tasks. Network software is “invisible” to end users and it
is simply used to facilitate the access those users have to network resources, in a seamless
way.
The basic functionality has user management and file management. User management allows
administrators to add or remove users from the network. File management enables
administrators to explain the location of data storage and user access to that data.
Through the network software allows multiple devices such as desktops, mobile phones, tabs,
laptops and other networks to connect each other.
Examples for scenario
 Internet
Internet is a globally connected system of servers and computers that depends on networking
software to verify accessibility by end users. (https://www.sdxcentral.com, n.d.)
2.4 What is the Server?
A specialized machine or software used to connect multiple clients for a service. (Local or
over internet). It may be physical or located on a cloud.
Word “Server” is not associated with any machine, it is a role which can be assigned to any
computing machine. A desktop computer may be a server.
In client/server model is fulfill with requests from client programs which is running other same
computers. In given application is function as a client with request service from other programs
and server request from other programs.
Figure 23: Server
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Types of Server
 A Proxy Server
Proxy server is an intermediary server between client and the internet. Proxy servers have
some functionalities. Those are network connection sharing, firewall and network data
filtering and data caching etc.
 An Application Server
It is designed to install, operate and host applications and associated services for end users, IT
services and organizations. It provides the business logic for an application program.
 A Virtual Server
It shares hardware and software resources with other operating systems versus dedicated
servers. This server is very popular in web hosting environments. Because they provide fast
resources control and cost effective.
 A Mail Server
Handles e-mail over a network or over the internet. A mail server responsible for receives
mails from client computers and deliver them to other mail servers.
 A Policy Server
A policy server is a security element of a policy-based network. It provides authorization
services as well as ease tracking and control of files.
 A Blade Server
A Blade Server includes of a chassis containing multiple thin, modular electronic circuit
boards, called as server blades, with each blade being dedicated to a single application.
Importance of Servers






Gives Scalability
Adds Reliability
Seamless Connectivity (remote and email)
Improves Collaboration
Makes for Faster Expansion
Allows Centralized and Automated Backup Systems
Best servers and specification
These days most of the organizations are using different types of servers. So we have to
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choose best server and specification before design the network system.
Dell PowerEdge T20 [barebones]
CPU
Intel
Pentium
G3220
Graphics
Intel HD
Graphics
RAM
4GB
Storage
No drivers
included
Connectivity
Up to 12 x USB
ports, VGA, serial,
2xPS2, Gigabit
Ethernet
Dimension
(W x D x
H) 17.5 x
43.5 x
36cm
Storage
40TB
HDD
Connectivity
Dimension
8 x USB 3.0,
17.5 x 37.5
serial, video, 2 x
x 43cm
DisplayPort, audio,
Gigabit Ethernet
Figure 24: Dell Server
Lenovo Think Server TS150
CPU
Graphics
Intel Xeon Intel HD
E3-1200 v6 Graphics
P4600
RAM
64GB
Figure 25: Lenovo Server
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Dell PowerEdge T30
CPU
Graphics
Intel Xeon Intel HD
E3-1225 v5 Graphics
P530
RAM
64GB
Storage
six SATA
HDD
Connectivity
Dimension
10 x USB ports,
17.5 x 43.5
HDMI,
x 36cm
DisplayPort, VGA,
serial, PS2, Gigabit
Ethernet
Figure 26: Dell PowerEdge
Fujitsu Primergy TX1310 M1
CPU
Graphics
Intel Xeon Intel HD
E3-1226 v3 Graphics
P4600
RAM
16GB
Storage
2 x 1TB
HDD
Connectivity
5 x USB 3.0, 2 x
Gigabit Ethernet
Dimension
17.5 x 42 x
39.5cm
Connectivity
Dimension
Figure 27: Fujitsu Primergy
HP Proliant Microserver Gen8
CPU
Graphics
RAM
Storage
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Intel
Celeron
G1610T
Matrox
G200
4GB
No drives
included
4 x USB 2.0, 2 x
USB 3.0, VGA, 2
x Gigabit Ethernet
23 x 24.5 x
23cm
Figure 28: HP Proliant Microserver
2.5 Importance of having compatible devices and related software
It’s easy to design and build a network securely and serves the organization well by having a
good understanding of the types of network devices. When we carefully monitoring ongoing
security and availability of network, then we can quickly spot hardware issues, configuration
issues and attacks. The network devices work as a group and have a single purpose which
securely transfers data as fast as possible.
Also networking software is a foundational component for any network. It helps
administrators deploy, manage, and monitor a network. Traditional networks made by special
hardware such as switches, routers that bundle the networking software into the solution.
Through the Software defined networking (SDN), making it easy to innovate and adapt the
network to quickly meet changing network demands.
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