Network System Administration Report 2022

Network System Administration

Abstract
Any network can face network connectivity issues or performance based problems. The main
culprits for these issues are DHCP and DNS. Thus, this indicates that the existing system
protocols require proper configuration. The purpose of this report is to implement a proposed
network design by utilizing the Linux network services. The installation and configuration of
the required TCP/IP suite i.e., DNS and DHCP server, including SSH securing, iptables is
done. The report is concluded with the results obtained from the tests and evaluation of DNS,
DHCP and virtual hosts.
Keywords: DHCP, DNS, SSH, iptables, Network System administration

Table of Contents
1. Introduction.......................................................................................................................1
1.1 Background................................................................................................................1
2. Literature Review.............................................................................................................2
2.1 Summary....................................................................................................................3
3. Scope and Limitations of the Project..............................................................................3
4. Proposed Network Design................................................................................................3
5. Experimental Work & Analysis......................................................................................4
5.1 Installation and Configuration of DHCP Server....................................................4
5.2 DNS Server in Virtual Machine...............................................................................9
5.3 Real Host and Virtual Host Set-up........................................................................20
5.4 Client/Server Configuration and Interactions......................................................27
5.5 Quality of Service Implementation........................................................................30
5.6 Securing SSH...........................................................................................................31
5.7 iptables......................................................................................................................36
6. Testing and Evaluation...................................................................................................38
7. Conclusion.......................................................................................................................41
References...............................................................................................................................43

1. Introduction
A network comprises a collection of systems like server platforms and desktops which
are connected to share the resources. The resources can either be the storage devices, folders
or printers and so on. Network offers a centralized accessing of resources which is utilized by
all the organizations. It is essential to take care of the network operations, which is
challenging. Additionally, the network must also be secured from the hackers. The most
common problems include network, systems and resource configuration. The complexity can
be determined by the size of the network. And the advancement in the telecommunication
and its market has impact on the hardware and software market where the users are setting up
system and networking together without having complete knowledge about networking,
systems and security.
In this report, the aim is to implement a proposed network system design in the
existing system, where the Linux network services will be used. The intension is to enhance
the existing network system and provide a new network design that is better that the existing
network system. To meet the new requirements of the proposed network design, the DNS,
and DHCP (Dynamic host configuration protocol) might need installed and configured.
1.1 Background
The network based problems are mostly faced by the network administrators, end
users and the owners of businesses. With the advancing mobile technology, the corporate
networks are including new complicated layers, which complicates things more. This
demands the need of faster and highly secure technologies to face the connectivity issues and
other issues. But, while setting up the systems, the key point which leads to disruption
includes loss of main power source, wrong cabling/wireless configuration, misconfigured
protocols and misconfigured network services. On the other hand, it is highly essential to take
care of the problems related to rights, credentials and permissions; network performance; and
problems related to TCP/IP or protocols. The other problem that must be considered is client
computer access shared resources’ configuration. Thus, the target is to troubleshoot and get to
the problem’s root cause, and make necessary changes in the proposed design (J. Shimonski,
2009). The troubleshooting methods is effective approach as it has the capacity of solving the
actual problem, and it is time consuming but effective method for finding the exact issue.
However, it is difficult, but necessary as working on a network could be confusing for
troubleshooting. Moreover, the network services must be enhanced to enjoy its offered
facilities.
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2. Literature Review
As per (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.
As per (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.
According to (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.
It is stated by (Courcoubetis and Weber, 2012) that, to design and manage any shared
infrastructure, an individual should consider the fact its participants would make self-
interested and strategic decisions in terms of their desired resources contribution or cost
sharing that they can manage.
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As per (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 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.
2.1 Summary
From the literature review it is evident that the network system administration is a
challenging task, because the protocols like DHCP is vulnerable to attacks. Therefore, the
network and their users must have enough knowledge to secure their network. The future
network development like SDN’s benefits are discussed which is expected to help the
network system administrator’s issues in managing the network. On the other hand, this
study helps to understand 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 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. Scope and Limitations of the Project
This project’s scope is to effectively manage the responsibility of the network systems
administrator, which includes responsibility of monitoring and taking care of the daily
updates and daily network operations to help the organization work effectively.
Limitations of this project are listed below:
i. Failure of data communication.
ii. Risk security
iii. Expensive set-up
iv. Professional support
4. Proposed Network Design
The existing system is improved with the following proposed network design.
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Figure 1: Proposed Network Design to be implemented
The above network design demands installation and configuration of the following:
 DNS server
 DHCP server
 Client/server
 SSH securing
 iptables firewall
 Real host
 Virtual host
5. Experimental Work & Analysis
Ubuntu is utilized for examining the existing network system services.
5.1 Installation and Configuration of DHCP Server
Use the command shown below to install DHCP server in Linux system:
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Restart DHCP Server
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