Network System Administration Australia Report 2022

Network System Administration

Abstract
Network contains a collection of servers, computers, network devices, mainframes,
peripherals, and other devices that are linked with each other for data sharing. The
complexity of a network increases with the increase in its size. Internet is the best example of
network, where millions of people are connected globally. There are high possibility that a
network could have connectivity and performance related issues. The reason behind these
problems can be the TCP/IP suite, the DHCP and DNS. The aim of this study is to improve
the performance of the existing network system, with a new network design. Therefore, a
proposed network design is implemented in the existing system. Additionally, its protocols
need effective configuration. Linux network services are used in this implementation. The
necessary installations and configurations are carried out (i.e., DNS and DHCP server,
including SSH securing, iptables installation and configuration). At last, the DNS, DHCP and
virtual hosts are tested and evaluated to determine their working conditions.
Keywords: Network System Administration, DNS, DHCP, SSH, Iptables, Virtual Hosts

Table of Contents
1. Introduction.......................................................................................................................1
1.1 Background of the Project........................................................................................1
2. Literature Review.............................................................................................................2
2.1 Overview.....................................................................................................................2
2.2 Summary....................................................................................................................3
3. Project Scope.....................................................................................................................4
4. Project Limitations...........................................................................................................4
5. Proposed Network Design................................................................................................4
6. Experimental Work and Analysis...................................................................................5
6.1 Installing & Configuring DHCP Server..................................................................5
6.2 DNS Server in the Virtual System.........................................................................10
6.3 Set-up of Real Host & Virtual Host.......................................................................21
6.4 Client/Server Configuration & Interactions.........................................................28
6.5 QoS Implementation...............................................................................................31
6.6 Securing SSH...........................................................................................................32
6.7 iptables......................................................................................................................37
7. Testing and Evaluation...................................................................................................39
8. Conclusion.......................................................................................................................42
References...............................................................................................................................44

1. Introduction
Network contains a collection of servers, computers, network devices, mainframes,
peripherals, and other devices that are linked with each other for data sharing. The
complexity of a network increases with the increase in its size. Internet is the best example of
network, where millions of people are connected globally. In contrast to all types of computer
issues the network problems can be considered as the worst issues (Stegner, 2019). The
network can have resources such as storage devices, printers, files, folders, etc. The
centralized resource access is facilitated by the networks, whose benefit is enjoyed by the
organizations. It is highly important to pay attention to the network operations, because it is
not an easy task. Further, the network security is crucial step which helps to secure the
network from the attackers. Configuration is the common network problem. The network
problem’s complexity could be identified based on the network’s size. Any organization must
has a network system administrator who have experience and skills of handling network
issues.
The purpose of the following report includes implementation of a network system
design, which is proposed to resolve the issues faced in the existing system. The Linux
network services are implemented in the new design. Thus, the current network system is
improved with a proposed network design and guarantees to offer better working experience.
This report will ensure to install and configure Iptables firewall, SSH, DNS, and DHCP for
meeting the requirements of the new network design. Further, QoS will be implemented for
application prioritization.
1.1 Background of the Project
Today, the technology has helped the business to access everything via internet, for
instance, networks are required for tasks like from document printing to attachment
downloading from the email. There are various types of network services like LAN, PAN
(Personal area network), WAN, MAN, WLAN, CAN, SAN (storage area network), EPN
(Enterprise private network) and VPN (Virtual private network). A cross the internet, with
the extension of a private network, VPN permits its end users to send data and receive it as if
though their devices are linked with a private network, but though it’s not linked. Using the
virtual point-to-point linking, the end users could ensure remotely accessing the private
network (Bourgeois, 2016).
1

Some of the common network issues can be wireless network connection problems,
network outages, file inaccessible, IP conflicts, slower response from the applications, poor
quality and so on. The IT team must always be ready to handle most of the network issues,
and save both our time and money. If the organization's network problems is not fixed they
can result out as big issues which can impact the business (Antony, 2013). When any issues
arise in a network the network administrator’s job is to troubleshoot the network issues, but
this is a time consuming method (J. Shimonski, 2009). Moreover, they are supposed to take
extra care of permissions, rights, credentials, performance of network, and TCP/IP or
protocols based issues. The problems can also be in the configuration of the client’s computer
access shared resources. The mobile technology’s advancement is increasing the complexities
in networking. Thus, the business owners must take all necessary precautionary measures to
secure their organization’s network and its functioning.
2. Literature Review
2.1 Overview
This part of the report will focus on gathering knowledge and understand about the
network, their issues, who can handle it and need of network system administrators in an
organization, what challenges they face and how can the network be secured.
As per Courcoubetis and Weber (2012), design and managing the shared
infrastructure requires participant’s self-interest and strategic decisions.
According to Younes (2016), with the increasing growth and widening of the internet
the network security has become a major concern, and it cannot be denied. There are many
methods for providing network security in transport layer, application layer, and network
layer, but it is seen that the data link layer or the layer-2’s security isn’t addressed so far.
From this paper it is observed that the data link layer protocols utilized in LANs doesn’t have
security features. The network protocol like DHCP is mostly utilized for the configuration of
host, which works in the data link layer. On the other hand, the DHCP is determined to be
highly vulnerable to various attacks like DHCP starvation attack, DHCP rouge server attack,
and malicious DHCP client attacks. This has led to the development of Secure DHCP (S-
DHCP), which is a new scheme that helps in securing the DHCP protocol. This proves that
the DHCP need to be secured well with an effective approach.
According to Parmar (2015), it is determined that the firewall is essential for any
network to secure it from the unauthorized and malicious access of the attackers who intend
2

to harm the users. Thus, the firewall offers security features. The researcher talks about
keeping the systems updated is necessary, so the end users must install antivirus and take
necessary steps to be safe. On the other hand, the firewall also has the capacity of controlling
the flow of traffic in the internet.
As per Liu et al. (2018), at present the SDN (Software-Defined Networking) is a
popular talk in the field, as it is known for the future network development. SDN is expected
to implement various control plane and data plane layers. To manage the network
administration issues, the best option that is available today is known to be SDN. It offers
programmability, and it better than the traditional network. The implementation of SDN is
said to improve the traditional network’s functioning, but it is observed to have increased
network attack nodes. Therefore, it end ups to have new security problems.
According to Scott and Laws (2010), the industries of network services ensures that
the networks be to a major study as it provides common features of network services. The
network service specifically depend on other people’s suggestions to direct their customers to
a certain business, because it is difficult to know about the company’s competitors or
customers. Therefore, information exchange is needed through the knowledge network. The
network services require people for engaging their organization’s production, and thus it
maximizes the number of small companies in this industry. Moreover, with the increase of
number also the complexity increases when it involves people in it. Thus, it makes networks
service significant part of networking.
2.2 Summary
The summary of the above provided literature review is that it provided proof of the
requirement of network system administration as it is a challenging job, which requires
continuous monitoring and maintenance. The DHCP can be easily attacked and thus the
network and their end users should ensure to gain required skills that help in securing the
network. The advantage of having SDN in the future network development is studied, and it
is observed that it can assist the network system administrator to manage the network.
Additionally, the study even helps in understanding that for designing and manage any shared
infrastructure, an individual should consider the fact that its participants would make self-
interested and strategic decisions in terms of their desired resources contribution or cost
sharing that they can manage. Finally, the topic of firewall mechanism is said where it tells
3

the firewall’s importance for any network to secure it from the unauthorized and malicious
access of the attackers, who intend to harm the users.
3. Project Scope
In an organization, the responsibility of a network administrator is huge, where he is
held responsible to update the computer network and their operation as required. Any firm or
enterprise which utilizes more number of software platforms or computers require network
administrator. Because, they have the capacity of coordinating and connecting various
systems. Though, it sounds easy but actually it is not. The systems administrator and network
administrators are not same and their differences can be known by defining their work type in
the organization. In some organization the network administrators have to handle hardware
setup for troubleshooting the servers, but other organizations might have less focus.
However, their duties are divided as follows-Network hardware configuration like routers,
servers and switches; Computer networks repair and upgrading; network issues
troubleshooting; network design model assistance; software updating and deploying; Server
and operating system management; Basic testing and security measure implementation and
so on (Erstad, 2018).
Therefore, the scope of this project refers to effective management of network
systems administrator’s responsibilities such as monitoring and maintaining the day-to-day
updates and network operations. This ultimate purpose is to ensure effective operation and
performance of the organization.
4. Project Limitations
This project’s limitations includes that there are high chances for the failure of data
communication, followed by risk security and professional expert’s help. Moreover, it can be
expensive to set-up this network design.
5. Proposed Network Design
The network design that is proposed to overcome the existing system’s drawbacks is
represented in the below figure.
4

Figure 1:New Network Design
The following must be installed and configured in this proposed network design:
i. DNS server
ii. DHCP server
iii. Client/server
iv. SSH securing
v. iptables firewall
vi. Real host
vii. Virtual host
6. Experimental Work and Analysis
To check the existing network service Ubuntu is used.
6.1 Installing & Configuring DHCP Server
DHCP has a significant role to play such as it eases and improvises the IP addressing
accuracy, however there are chances that it can increase security issues. Moreover, it
decreases errors made while manually assigning the IP addresses, provides accurate IP
configuration, and effective change management (Kerravala, 2018).
5