LAN Infrastructure Design, Implementation, and Management: A Comprehensive Guide

This report delves into the intricacies of Local Area Networks (LANs), covering their technologies, design principles, implementation strategies, and management practices. It explores various LAN technologies, including wired and wireless options, and critically analyzes their suitability for different scenarios. The report then guides the reader through the design and implementation of a robust LAN infrastructure, incorporating security measures and performance optimization techniques. Finally, it discusses essential monitoring and troubleshooting tools for maintaining a secure, reliable, and high-performing LAN environment.

Introduction:
LAN is termed as local area network. The LAN is interconnection of several devices. The devices are
situated at fixed location. The LAN is established at several places lie offices, schools, homes,
colleges and other areas. A LAN is of both types either wireless or wired.
After reading this local area network report the concept about the LAN is cleared. This report is
divided into four learning outcomes. In first learning outcome what is LAN, the types of LAN
technology and which technology is best among those is discussed. In second learning outcome how
the LAN is implemented and what are the suitable components are used in the infrastructure is
discussed. In third section of learning the LAN is build and implemented with some security features
in the infrastructure. The several tests are also performed to check the efficiency of designed
infrastructure. In last section of learning it detail about the tools used for monitor and troubleshoot the
LAN infrastructure. It will also detail about the issue related to reliability, security and performance
are resolved and how performance is evaluated in the infrastructure is discuses in the report.

LO1 Understand the impact of LAN technologies
Task 1
1.1 critically evaluate different LAN technologies
Local area network- LAN is a collection of computers or associated devices which have a common
communication link. Communication link is used to pass information between the multiple computers
and other devices. Local area network used in many applications (Techterms, 2018).
Figure 1 local area network
Source: (Tech Terms)
Types of LAN-
Wired LAN- wired networks are also known as Ethernet networks. Wired network is group of two or
many computers or printers. Ethernet has very high connection speed which is from 10 Mbps to 100
Mbps so Ethernet is the fastest wired network. There are 3 common network topologies which are
very useful such as star network, bus network and ring network.
Wireless local area network- wireless network uses very high-frequency radio waves for
communication between the nodes. Wireless network also used in home and business networking.
Organization use wireless network to increase their existing wired network. There are 2 types of
wireless networks such as ad-hoc and peer to peer.
IEEE standards for Wired LAN (Ethernet IEEE 802.3) - Ethernet, IEEE 802.3 are most useful
standard for general data communication or computer networking. 802.3 specify the working
characteristics or the physical media of Ethernet. Ethernet standard is used to fulfill the requirement
or needs of growing technology. Ethernet supports data rate of 10 Mbps. Ethernet is used for the
wired networks for computers and Ethernet also provide supports to many large or small data
communication system.
IEEE standards for Wireless LAN (Wi-Fi IEEE 802.11)- there are many specifications in 802.11
family.

802.11- 802.11 use DSSS and FHSS spectrums are provide one and two Mbps transmission in 2.4
GHz band.
802.11a- 802.11a applies to the wireless LANs & provides 54 Mbps transmission in 5GHz band.
802.11b- 802.11b also applies to wireless LANs and provides 11 Mbps transmission.
802.11e- 802.11e defines the QoS supports for local area network.
VLAN- VLAN is a logical collection of network devices, servers, or workstations. VLAN provide the
network in which the different users or the network of computers are allowed to communicate in the
environment where there can be a multicast domain & single broadcast. VLAN is applied to achieve
security, ease of network management, or scalability (Charriere, 2018).
There are 5 types of VLAN such as
1. management VLAN
2. data VLAN- data VLAN I also called as user VLAN. The user VLAN is select for user-generated
data.
3. voice virtual local area network
4. default VLAN
5. native VLAN (Charriere, 2018)
Benefits of virtual local area network:
 Improved quality of services
 Improved security- virtual local area networks improve security of system by reducing external or
internal threats.
 Easier fault management
Repeaters- Repeaters works on physical layer. Repeaters are used to regenerate the signals before the
signals become weak.
Bridges- bridges works on data link layer. Bridge works same as repeater with some other functionality.
Bridges are used for interconnection of 2 LANs which are working on the common protocol. Bridge has
one input or one output port. Types of bridges
 Source routing bridges
 Transparent bridges

Figure 2 Bridge
Source: (Joe Onisick)
Hubs- hub is used to joint multiple wires which are coming from various branches. For example a
connector in the star topology which is used to joint various stations. Types of hubs
 Passive hub
 Active hub
Routers- Routers are devices same as switches that route data packet which is based on the IP
addresses. Routers are used to connect WANs or LANs together (Tyson, 2018).
Switches- switches are work on the layer of local area network. Switches are used for ‘forwarding
and filtering’ of data packets.

Figure 3 routers and bridges
Source: (Gael Charriere)
Coaxial cable- coaxial cables are used for the frequency signals because coaxial cable is work as a
communication line. Coaxial cables provide security of the signals from outside electromagnetic
interference. Coaxial cables are used in many applications such as microwave or RF transmission,
CATV distribution (Omnisecu, 2018) .
Fiber optic- fiber optics is a technology which uses glass or plastic threads for transmission of data.
Fiber optic transmits the data or information from one place to another place. Fiber optic cable
contains a packet of glass or plastic threads.

1.2 critically analyze traffic intensive services and their performance
Voice over internet protocol- voice over IP is a method which is used for the delivery of multimedia
sessions and voice communication over the IP networks.
Voice-on-demand – it is a programming system which permits customers to select & listen/watch to
audio or video content like TV shows and movies (Rogier, 2018).
Video and audio streaming- Storage size is derived from the length of media and streaming bandwidth
with the help of following method:
Storage size ( in mebibytes) = length ( in seconds) * bit rate ( in kbit/s) / 8388.608
Video bit rate ( in kbit/s) * estimate no. of people = no. of bandwidth ( in kbit/s)
Live streaming-
Length of video ( in seconds) * video bit rate ( in bit/s) / (8 * 1024 * 1024) = storage size ( in
megabytes)
Video bit rate ( in kbit/s) * estimate no. of people = no. of bandwidth ( in kbit/s)
Quality of service- QOS is the measurement and description of the complete performance of the
services such as cloud computing and computer network services. Quality of services is also used in
many application layer services like streaming video or telephony to define a metric which predicts or
reflects the quality of services.
Differentiated services and IP precedence- differentiated services classify the packets when the
packets enter into the local network. This classification is then applied to the flow of traffic. Flow is
explained by five elements; destination IP, Destination port, source IP, transport protocol and source
port (Rogier, 2018).
IP header has a TOS field which is placed among the total length field and header length field. IP
precedence is used first 3 bits of type of service to offer possible precedence value.
000(0)- routine
001(1)- priority
010(2)- immediate
011(3)- flash
100(4)- flash override
101(5)- critical
110(6)- internetwork control
111(7)- network control (Rogier, 2018)

1.3 Discuss LAN concerns and make recommendations to sustain network
security, reliability, and performance.
Latency- In an internet protocol network, latency is a time which is taken by a packet for entering and
leaving the network. The entering time of packet A = t0 and leaving time of packet A = t1. The
latency of packet A is t2= t1- t0.
Figure 4 Latency
Loss- when one or many packets of information or data are traveling across the network and fail to
reach at their destination, packet loss occurs.
Jitter- jitter is basically the variation in packet delay and it is used to measure the time differences in
packets inter and arrival times.
Bandwidth- bandwidth is the amount of information and data that is transmitted in particular amount
of time. Bandwidth is expressed in bytes per sec or bits per sec for digital devices (Chia, 2012).
Throughput- Throughput is the amount of data or material which is passing via a process and a
system.
Confidentiality, availability, and integrity are also called as CIA triad. CIA triad is a model which is
designed to guide procedures for information and data security.
Confidentiality- Confidentiality is defining as a set of instructions or rules that provide protection to
the personal information. Confidentiality is designed to prevent personal and sensitive information
from the unauthorized users.
Availability- availability gives guarantee of reliable access of the data by authorized user.
Availability checks only authorized user is able to access the data or information.
Integrity- integrity includes maintaining the accuracy, trustworthiness or consistency of data or
information over its complete life cycle.
Access control list- access control list is the network filter which is used by the switches or routers to
restrict & permit data flow into & out of the network interface (Chia, 2012).

Firewalls- firewall is a system or software which is used for network security. Firewall controls or
monitors outgoing & incoming network traffic.
Figure 5 Firewall
Source: (David K. Berchem)

LO2 Be able to design LAN infrastructures
Task 2
A.C 2.1 design a LAN infrastructure for the company which will facilitate all of their
requirements
Figure 6 LAN infrastructure
The infrastructure given above is a three-floor building where several departments are situated in each
floor of the building like Human resource department, Finance department, Sales and marketing
Department, Customer service department and IT support. This infrastructure has been designed using
switches which is a form of packet switching used in local area network. For network design
switching technologies are crucial since it allows traffic to be send where it is needed. Different

network switches are used in LAN switching, Routers if wireless displays reference to LAN and
Coaxial cable was widely used in Local Area network which is being replaced recently because of its
high-cost (Omnisecu, 2018).
A.C 2.2 critically evaluate the suitability of LAN components
Suitability of components of local area network can be defined through the below given parameters:
Availability:
This is a factor which is taken according to the point view of user. Taking this model proposed as an
example. When this topography of network is considered it is found that it is available fairly to the
users. According to the illustration it is established that even when the component does not work
properly or fails it is not going to affect the entire system. Although this is possible only in the first
level of networking. When it moves down to the second layer the situation will just be the opposite
where if there is a failure in the component then it is going to harm the whole system .Considering
this case it can be termed as maximum availability. It also takes in consideration these following
factors including:
Reboot time: It is the time which the device takes to perform its operations after the device has been
turned on.
Downtime: It is the time in which a device is not in action or cannot be taken in use (Techwalla,
2015).
Temperature Fluctuation: Random deviations in a system, Fluctuation becomes higher and frequent if
there is an increase in the temperature and it decreases when the temperature is absolute zero.
Security:
With the increase in the transmission of information electronically it is vital that security needs to be
considered in every phase of design and maintenance of local area network .Although a lot of
emphasis has been put on remote access and wireless networks. In organization, information system
works as the nervous system which requires great care to be secured properly. Since more and more
users requires access to resources of local area network, there needs to be a way to restrict and
identify what access they are granted and who is allowed to the network.
This architecture comprises of a complicated structure where it needs to have a robust security
system. Firewalls works on such issues in network communication. A free flow of information is
necessary in an organization like this in the premises with an access to internet. In between the two
forms of communication firewall acts as the secure , best bridge . Firewall works as a guard which
ensures meeting of specific conditions before entering into the network of an organization. In this
information is broken into packets in which there can be interaction with only the given authority.
Besides these secured modem can also be used along with cryptography enabled routers for secured
network communication (Techwalla, 2015).
Security can be achieved through various ways
First method involves firewall resource which has been explained above and others include WPA2 or
WPA for encryption of password on traffic from the internet. LAN requires security strategies which
are internal including anti-malware or anti-virus security , Through user activity hacking functions are
introduced to network. Taking an example many malicious programs or viruses operate off of a user
opening an email. Security design should be considered carefully to promote better security of LAN
to prevent vulnerabilities.

Scalability:
Scalability is the capability which a system, process or network has to deal with large amount of work
or the potential to accommodate the growth.
Scalability in local area network can be achieved by two ways:
Vertical- In this method more hardware including processor, RAM or more nodes is added. Load
balancer is also introduced which is going to help in routing the incoming calls to a lot of servers
depending on the routing algorithm used. As load is being shared across the servers, more loads can
be handled by the application.
Horizontal: In this method the application is architect by us in a way that it can behave properly in
parallel traffic. Checking of management of memory, cache , session and states needs to be done.
Session is used to maintain the information of the user in heavy load single server there are more
efforts required to manage the servers to check the possibility of being stateless. It responds to request
from the same user in parallel instead of replying serially.

LO3 Be able to implement LAN infrastructures
Task 3
A.C 3.1 build and configure a LAN (including services) to meet a given requirement
Figure 7 Infrastructure of LAN

In the above diagram the infrastructure of footfalls is designed as per the requirement given. The 3
floor infrastructure is designed in which each floor has 5 set of department that communicate with
each other.
The new set of security policies are used in the infrastructure design. After developing the
infrastructure for footfall the several department in footfall do their work in an efficient and secure
manner.
In infrastructure the routers, switches, co-axial cables, servers and computer devices are used for
infrastructure deign.
Figure 8 first screenshot for CLI command

Figure 9 second screenshot for CLI command

Figure 10 third screenshot for CLI command

Figure 11 fourth screenshot for CLI command

Figure 12 fifth screenshot for CLI command
A.C 3.2 implement network security on a LAN
Figure 13 switch configuration for LAN infrastructure
In LAN network the ACL play very important role to provide the security feature to the network. It is
used to control the traffic flow inside the LAN network. In ACL only the server and internet is
accessed in the network. By using the ACL in network it is determined that what objects is allowed to
access the objects (Boteler, 2017).

Figure 14 Router ACL configuration
Many ways are present to secure the LAN infrastructure some of which are:
 Mapping & auditing
 Filtering the MAC address
 Protect the router & switch with password
 For authentication use 802.1X
 Installing firewalls in the network
 Use security protocols such as WPA & WPA2 for the password encryption
Only admin is given the authentication to the full infrastructure. If any change is done then it will be
done through the admin end. Each department is

Figure 15 Switch password protected
Figure 16 router password protected
In the above image shown the router & switch is password protected. The password is encrypted so
no other than the admin see the password in the network.

A.C 3.3 critically review and test a LAN
Sr.
No.
Test Case Expected
Result
Actual result Feedback
1. Inter
department
ping test is
performed?
The data is not
transfer in
between the
inter
department.
The data is lost
100% in this
case.
Executed
Successfully
2. It manager to
other
department
ping test is
performed?
All data is
transferred
successfully.
The data
packet loss is
0% in this.
Executed
Successfully
3. Router is
password
protected?
Access is
granted to
authorize
person.
It can only be
granted access
to footfall
people.
Executed
Successfully
4. Switch is
password
protected?
Access is
granted to
authorize
person.
Grant access to
authorized
persons.
Executed
Successfully
5. DNS and
HTTP is
tested?
The HTTP
and DNS
work
efficiently.
The
connection
establish
successfully.
Executed
Successfully
6. Speed of
network is
tested?
The speed is
up to the
mark.
The data is
transferred
over the
network with
good speed.
Executed
Successfully
7. The overall
network is
tested?
The whole
network is
efficient to
use.
Without any
cause it is used
efficiently.
Executed
Successfully
8. The ACL is
used in the
network?
The Access is
properly
granted to the
users,
All users are
granted the
specific set of
accesses in the
network.
Executed
Successfully
9. The data is
encrypted?
All data that is
transfer is in
encrypted
form.
The data is
protected.
Executed
Successfully
10. The traffic is
managed
efficiently?
The network
runs under
heavy load.
Network
manages the
load
efficiently.
Executed
Successfully

Figure 17 ping test case 1
Figure 18 ping test case 2

Figure 19 ping test case 3
Figure 20 ping test case 4

Figure 21 ping test case 5
Figure 22 ping test case 6

Figure 23 ping test case 7
Figure 24 ping test case 8

Figure 25 ping test case 9
Figure 26 ping test case 10

Figure 27 Test case 11
Figure 28 telnet access test case
LO4 Be able to manage LAN infrastructures
Task 4
A.C 4.1 critically discuss how this LAN infrastructure will be monitored and
managed (via troubleshooting) if there is any issue during post implementation
period.
For the enhancement of performance in the network troubleshoot and monitor tools are used. Several
software’s in market are available that can be used for the process of performance enhancement of
LAN network.
Monitor tools: In LAN network the monitor tool is used to check the connection in between the
hosts. To check the availability of other host it is used. It is used to ensuring the availability & overall
performance of hosts & network services (Tabona, 2015).
1. Nagios: The feature of alerting, reporting & event handling. It is used for the purpose that the
system is always up & running.

2. Capsa Free: The feature if this is it can be support the 300 different types of protocols. This can be
used to analyse the traffic in network, issues troubleshooting & analyse packets.
3. Open NMS: It offers the management of automated discovery, notification, performance & event
management (Mitchell, 2018).
4. Zenoss Core: This is IT monitor platform that will monitor the servers, networking, storage &
virtualization and also provide the performance & availability statistics.
5. Fiddler: It is the web debugging software tool. It gives the detailed description of HTTP traffic
and also used for testing the performance of website.
6. Network Miner: This can capture the packet from the network and parse the data into extract
images & files.
7. Pandora FMS: This is the performance, network monitoring & availability management software
tool.
Troubleshoot tools:
1. Cacti: In this software tool it is used for not only tracking the interface utilization bust also
availability & the response time of network.
2. TCP trace route: Instead of ICMP it uses the TCP for tracing the path. It can also be used to
tracking down the firewalls.
3. Curl: It is used in the command line to transfer the data to and from the server in the network.
4. Wireshark: It is used to find the connectivity issue, dependencies & low application in the
network.
5. Smoke Ping: It is used to measure the packet loss, network latency.
6. Snort: It is used for the traffic analysing, storing the problematic packets, creating the alerts in the
network.
7. Nmap: It is free tool used for security scanning & security auditing in network (Mitchell, 2018).
A.C 4.2 resolve LAN issues to improve security, reliability and performance
In LAN network if any issue arise it will degrade the performance of the network. The issue related to
security, performance & reliability can be handled carefully (Azerual, 2013).
Performance & reliability issue resolution is:
The performance & reliability is the biggest measure in the LAN network it can define how effective
the network. In network the subnets, drivers, storage are used to increase the performance (Geier,
2014). The measures that can be taken to improve the network performance are:
1. Use compression techniques in the network this may reduce the bandwidth consumption.
2. Out of bandwidth can be managed: In this the bandwidth that is wasted gets reduced. Some
devices in the network sometimes may consume bandwidth in appropriately. This bandwidth
consumption reduces the performance of network.
3. Effectively manage the network traffic.
4. The quantity of servers in the network will enhance the performance.
5. The storage capacity increased.
6. Keep junk traffic out of the network (Azerual, 2013).
7. The packets may be send according to prioritized this may improve the performance.
8. Delete the history and lost packet cache from the network. This deletion enhances the
performance of network by great amount.
9. Instead of hubs the switches is used in the network.
10. LAN cards is installed in the network this will increase the performance of the network.
Security issue resolution is:

In LAN network several techniques is taken into consideration to solve the security problems. The
techniques include authentication, authorization, firewalls installation, anti-virus installation
(Pascucci, 2013).
1. Mapping & auditing is performed.
2. The network is secured physically.
3. The VPN is used to encrypt the selected servers and PCs.
4. Considering MAC address filter.
5. In network the firewall can be installed.
6. In network the anti-viruses in enabled.
7. In network the proxy servers can be used.
8. In network the encryption is done.
9. In network the Access list is generated. This will provide the level of authentication to the each
individual user (Pascucci, 2013).
10. The switches and routers will be password protected in the network.
A.C 4.3 critically evaluate the performance of a LAN
In LAN network several issues are faced while the packets are transfer in between the
host. The issue like bandwidth, speed, connection & devices. This issue may be resolving
to improve the network performance.
1. The routing table is updated every time with every new entry the table is updated.
2. The demand of network is reduced.
3. The host that waste the bandwidth will be removed from the network.
4. The load on the network will be maintained efficiently to improve the performance.
5. The capacity of the circuit is improved.
6. The network is protected against the viruses.
7. The network is analysed to find any data leakage issue.
8. Use compression and encryption techniques to enhance the network performance.
9. Dedupe the data: In this the data which is unique and very much important to the network is
taking the backups and rest is removed from the network this will increase the network
performance.
10. The capacity of storage and servers are increased in the LAN network (Casey, n.d.).
In LAN network the monitor and troubleshoot tools are used to enhance the network performance. In
network if any data packet is lost in between the host then the alert is generated and the sender knows
the issue and take the appropriate action regarding the issue. Several data monitoring tools are present
that are not only used for network monitoring but also for report building of LAN network (Azerual,
2013).

Figure 29 Report 1 of PDU
Figure 30 Report 2 of PDU

Figure 31 RIP routing IP routes
Figure 32 pinging test case 1

Figure 33 pinging test case 2
Figure 34 pinging test case 3

Figure 35 pinging test case 4
Figure 36 pinging test case 5

Conclusion:
LAN is modern and standalone technology used at several places for reliable data transfer. LAN
is used as either wireless or wired. This assignment report is discussed in four parts. In first part
all the theatrical concepts related to LAN was discussed. In second section the LAN network was
configure with the suitable components. In third section the LAN infrastructure was built with
some security standards. After implementation several test case was applied to check the
efficiency of network. In last section of report the tools used for monitoring the infrastructure
was discussed. Also the security, performance, & reliability issue affect the infrastructure was
discussed.

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