Network Security Fundamentals - Vulnerabilities, Devices, Segregation, Firewall Policies and Rules

This article discusses network security fundamentals including vulnerabilities associated with the system, security devices such as firewall, IDS/IPS, honeypot, and routers/switches, the need for network segregation, and firewall policies and rules. It also provides insights into Lucent Pharma's network security policies. The article is relevant for students studying network security and related courses in colleges and universities.

Running Head: NETWORK SECURITY FUNDAMENTALS
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Network Security Fundamentals
Name of the Student
Name of the University
Author’s Note

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Table of Contents
1. Vulnerabilities associated with the system.........................................................................2
2. Explanation of the security devices........................................................................................3
3. Explanation for placing security devices..............................................................................5
4. Need of network segregation.................................................................................................6
5. Firewall policies and rules.....................................................................................................8
6. Developing set of IDS/IPS policies........................................................................................9
7. Security policies needed for Lucent Pharma network..........................................................10
8. Designing the proposed secured network design.................................................................12
Part 2........................................................................................................................................13
Bibliography.............................................................................................................................17

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1. Vulnerabilities associated with the system
The network topology needs to be implemented by the organization “Lucent Pharma”
faces number of vulnerabilities. The vulnerabilities that are generally present within the
network are as follows:
Patches missing: The patch on the server can be missed which generally assists in
permitting unauthenticated command prompt into the environment of web. This can be taken
as an advantage by the attackers and rogue insider. It is found that in order to avoid this type
of challenges and vulnerabilities, it is very much essential to be careful during the application
of the patches to the entire servers. It is identified that the network security related practices
or steps needs to be used by updating the OS on the latest patches of security.
Default passwords: It is identified that passwords are not categorized within the
section of network vulnerability however it is found that there is number content management
system, database servers as well as web applications that are configured by using number of
default or weak passwords. This type of issue can be resolved by conducting proper test
regularly while considering utilization of password management tool. It is identified that
intruder is lockout after defining number of failed login attempts.
Firewall rule bases misconfiguration: One of the most dangerous as well as biggest
assumption is misconfiguration of the firewall. It is identified that due to misconfiguration of
the firewall number of serious security related issues and challenges can occur within the
system. It can also lead to entry of unauthorized users into the web environment that further
can cause number of cybersecurity as well as ethical issue due to misuse of important as well
as confidential information. It is found that in order to resolve this issue and problem, it
necessary to implement the security policies quite effectively.

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Wireless access points: Wireless Aps generally assists in providing proper
connectivity to the users with appropriate proximity within the entire network. It is found that
wireless tacks by ward drivers can generally create number of significant changes within the
network. This type of vulnerabilities needs to be resolved in ore to secure the sensitive as
well as confidential data as well as information of the organization quite effectively.
Utilization of USB flash drives: The utilization of USB flash drivers is considered
as one of the most common technique with which the network of the organization can also
get infected. In order to resolve the security vulnerabilities, it quite important to utilize proper
security related policies within the organization.
2. Explanation of the security devices
The security devices as well as controls that are utilized within the network generally
do not compromises network security as well as performance of the network.
Firewall: Firewall is defined as one of the system that is mainly designed in order to
prevent unauthorized access from a private network. It is identified that firewall helps in
preventing the unauthorized internet users in order to restrict the data access from the private
network that is connected to the intranets. It is identified that that firewalls are mainly
categorized into several types including packet filtering, circuit level gateway, and web
application firewall as well as proxy server. It is identified that firewalls generally set number
of rules which are mainly applied to each of the packet. It is found that the rules generally
helps in deciding whether a packet can be able to pass or it can get discarded.. Usually
firewalls are generally placed between the networks that are trusted as compared to the
network that is less trusted.
IDS/IPS: IDS and IPS are the processes that are generally very much helpful in
determining the event that mainly occurs in the network in order to identify the signs of

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different violations, incidents as well as imminent threats for the security policies of the
organization. The IDS generally works for identifying intrusions as well as various types of
configuration related errors that generally affect the company including virus as well as
malware infection. It is identified that IDS generally assists in providing the network with a
level of preventive security against various types of suspicious activities. IDS generally assist
in achieving the objective with the help of early warning that generally aims at system
administrators. On the other hand, IPS is one of the devices that generally help in controlling
the access to IT networks for protecting the system from any type of abuse or attack.
Honeypot: Honeypot is a decoyed computer system in order to trap hackers or
tracking various unconventional or new hacking methods. They are generally designed for
engaging as well as deceiving hackers as well as identifying various types of malicious
activities that are generally performed over the internet. There are number of advantages of
honeypots. It is identified that honeypots provides ease when they are generally employed.
Another significant advantage is that they generally assists in seeking information of hackers
and the information are considered to be quite valuable in order to study as well as uncover
the motivations of the hackers.
Routers/switches: It is identified that both router and switches are computer
networking devices that generally helps in allowing more networks that are required to be
connected with other computers, network devices as well as other types of networks. It is
identified that function of router are quite different and they are generally integrated within a
single device. Routers generally connect two or more logical subnets that generally des not
map within a single interface of the router. Routers are generally considered as the workhorse
that generally helps in transferring packets of data between various networks in order to
establish as well as sustain proper communication between the nodes within an internetwork.

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3. Explanation for placing security devices
The devices that are generally placed within the lucent Pharma network are due to
some of the reasons that are generally explained below:
Firewall: Firewall will be utilized within the network for restricting unauthorized
users entry within the private network. They are used in the network of Lucent Pharma so
that the users of internet cannot directly be able to enter within the private network of the
organization that is mainly connected with the intranets. It is found that all the messages as
well as information needs to be pass through the firewall so that the information or message
that can create cyber security related issues can be blocked and thus they are not able to enter
within the private network of the organization. They are generally helpful in limiting the
access of the network and generally allow access through appropriate secure authentication
based logins.
IDS/IPS: Both IDS as well as IPS are generally placed within the network so that
they can be able to analyze the sings of occurrence of different types of violations as well as
security related incidents. IDS are placed so that they can be able to stop the incidents
whereas IPS generally becomes one of the parts of the network for detecting as well as
stopping various types of possible incidents. IDS as well as IPS constantly visit the network
and identify various types of possible incidents and logging information about tem and
generally play a great role in preventing the incidents and then reporting to the network
administrator. In addition to this, some of the networks utilize IDS/IPS for determining
different types of security related policies.
Honeypot: Honeypot is one of the computer systems that are generally set up for
acting as proper decoy in order to lure the cyber attackers and for detecting attempts of
unauthorized access within the information system. It is basically comprises of number of

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applications, computers as well as data that generally helps in stimulating the behaviour of
the system that are generally appeared to be part of the network that are generally isolated as
well as monitored properly. It is found that all communication with appropriate honeypot is
found to be hostile. They are utilized for attracting the attackers in order to reflect on the
study about their movements as well as behaviours and thus they generally helps in playing
an important role in securing the network of the organization.
Routers/switches: It is identified that switches are mainly utilized in order to connect
the server. It is found that a switch general serves as one of the controller that generally help
in enabling proper networked devices in order to talk efficiently. The switches help in saving
money as well as assists in enhancing the productivity of the employees. Other hand, routers
are generally utilized for checking the source as well as destination of the IP address in order
to look up the destination of the entire attack in the routing table of IP.
4. Need of network segregation
It is identified that Lucent Pharma organization generally needs network segregation
into multiple domain and thus it is reflected that it is necessary to utilize VLANs. Virtual
LAN is one of the logical sub networks that generally group together a number of devices
from different types of physical AN. It is found that larger computer networks of the larger
business often set up the entire VLANs in order to re-partition their networks for improving
traffic management. It is identified that several kinds of network generally helps in
supporting virtual LANs that generally include both Wi-Fi and Ethernet. It is found that
VLANs helps in bringing proper security benefits to the larger networks in order to allow
proper control the devices over local access. WI-FI helps implements the networks by
utilizing wireless access points that generally helps in supporting the VLAN’s. In addition to
these VLANs, assists in providing advantages that are generally listed below:

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Physical layer transparency: It is found that VLANs are very much transparent on
the present physical topology and medium over which the entire network is entirely
connected.
Security: It is identified that separating system that generally have sensitive data
helps in minimizing the chances that is gained by the people to access information when they
are not authorized to see it. This is helpful only due to the utilization of VLANs and thus it is
analyzed that utilization of VLANs are quite helpful in securing the data and information of
the organization.
Cost: It is identified that segmentation of VLAN to smaller LAN generally
considered being cheaper as compared with network as well as routers as routers are much
more costlier than the network.
Broadcasts: As one of the main element of VLAN does not helps in passing
broadcasting traffic to nodes that are not a part within the VLAN and it generally assists in
reducing the broadcasts. It is found that access lists generally helps in providing proper
network administrator with a appropriate way for controlling the traffic of the network. It is
found that an access list is one of the tables that are created by the network administrator for
addressing the access of the entire network.
Performance: It is found that proper monitoring of the network utilization generally
assists in allowing the network to create proper network administrator for creating VLANs
for minimizing the number of router hops and for enhancing the apparent bandwidth for the
various users of the network.
Departments: The various departments of the organization that generally have large
number of network users generally set VLAN or VLANs are generally connected across
various departments that is mainly dedicated for particular types of employees.

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5. Firewall policies and rules
Firewall is considered as one of the appliance that is mainly designed for controlling
the flow of entire internet protocol or electronic equipment. Firewall are generally utilized for
examining the entire network traffic in order to enforce various types of policies that is
dependent on instructions that is mainly contained within the entire rule set of the firewall.
The policy statement of the firewall is mainly categorized in order to give appropriate
guidance on the required firewall. It is found that a network firewall is mainly needed in all
the instances where the confidential data are generally processed It is found that both the
host firewall as well as network generally helps in affording protection to the operating
environment so that redundancy of control is provided if the additional security that is
provided is compromised or fails. It is found that proper awareness is generally raised on the
significance of a properly configured firewall. In addition to this, the rules that are utilized by
the firewall are provided below:
Rule set 1: Responses to internal requests must be allowed. It is found that in most
implementation, it is very much desirable to allow the response to proper internal requests in
order to achieve information. It is found that in dynamic as well as stateful firewalls, the most
easily accomplished by matching the traffic into outgoing requests within proper state table.
It is found that in simple packet filtering, this must generally be accomplished with
appropriate rule for the external filtering in context to router.
Rule set 2: The firewall must not be accessible directly from the public network. If
the hackers access the firewall directly, then can be able to modify or delete the entire rules
and generally helps in allowing unwanted traffic. Therefore, firewall must not be allowed to
access from other networks directly. If the hackers or cybercriminals generally compromise
the firewall and utilizes the permission for accessing other clients or servers of the network,
the they may cause additional mischief or damage.

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Rule set 3: All the traffic must be allowed out from the trusted network. It is not
considered wise for restricting the network. As a proper rule, it is necessary to restrict the
outgoing traffic unless separate router is generally configured for handling the entire traffic. It
is found that assuming that the dangerous traffic is inbound and screening the traffic
generally works for the entire firewall. It is found that this level of trust is considered to be
fine for most of the organizations. If the work organizations generally require proper control
over bound traffic then it is quite necessary to utilize proper separate router.
Rule set 4: It is found that the rule set for the simple mainly transport protocol data is
mainly used. It is found that the packets are mainly governed by proper rules in order or
allow the firewall as well as for routing well-configured SMTP gateway. It is quite necessary
to email traffic server. It is found that some of the hackers generally tries for disguising
dangerous packet to fool a firewall.
6. Developing set of IDS/IPS policies
IDS are mainly considered as one of the proper automated system that mainly helpful
in analyzing as well as determining the entire network traffic in response to number of
activities that can match through different patterns of malicious activities. In order to
determine as well as analyze the traffic, number of polices are well as needs are needed to be
developed by the network administrator so that the security of the network is maintained In
addition to this, the policies are very much advantageous in mitigating the challenges of
cyber security from the entire network. The policies that are needed to be developed within
the entire network are listed in the table below:
1) The perimeter firewall should always e located between the switch as well as
router.

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2) Inbound as well as outbound of the entire network must be restricted and therefore
t must be dependent on the classification of the network that is mainly determined with the
help of the procedure of risk assessment that is mainly utilized.
3) Restricted data must be hold by the system for the inbound and inbound traffic so
that it can be successfully restricted form the business in order to function al other outbound
as well as inbound traffic.
4) Proper update is required in the configuration of the firewall for successfully
updating new types of vulnerabilities that are mainly identified.
5) Proper monitoring of IDS as well as IPS must be done appropriately in order to
restrict the data successfully.
6) It is necessary to undertake risk analysis in order t identify the internal as well as
restricted system and IDS and IPS.
7) Both IDS and IPS must help in restrict the data environment for properly
configuring the alert of personnel for various suspected compromises.
8) It is quite essential that IPS as well as IDS must be properly baseline with the help
of the signatures in order to keep the entire data up to date.
7. Security policies needed for Lucent Pharma network
The security related issues, which are necessary for the network of Lucent Pharma,
are listed in the below table:
Sys admin: The entire responsibility of network is dependent on the Sys Admin. The
rle of the sys is as per the functions of the system so that the entire network is properly
intended for work. If any type of security issues generally rises within the network, then it is
the responsibility of Sys admin to resolve the security related challenges quite effectively so

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that the system will be kept secured. Proper security related policies are required to be
utilized by the sys admin to keep the entire network secure.
Audit: Audit plays a significant role in the networking fields as lot of factors is there
that are generally dependent within the functionality off the entire system. It is found that the
policies that are generally utilized within the devices must per appropriately perform for the
system requirements. This concept is generally utilized so that the person can be able to take
care the entire network quite effectively. If is found that any type of error that is found within
the network must be appropriately helpful in securing the entire system. Appropriate planning
is required to be performed related wit policy in order to deal with the changes that are
required to be one within the entire system.
Network: The policy, which is mainly associated with the network generally, assists
in reflecting that the packets are transferred in the network can be accessed quite easily. The
main motive that is present for the network is to reduce the time that is mainly related with
the delivery of packets. It is necessary to secure the entire network quite effectively so that
none of the activity can create negative impact on the network.
Security: Security is found as one of the essential perspective of networking. As there
are number, of attacks that are done on daily basis on the network and thus the entire
functions of the network got affected. In order to mitigate the challenges, proper policy is
generally used in the concept in order to enhance the security of various networks so that it
can be able to create proper impact on the internal as well as external working of the entire
organizations. It is identified that there are number of policies as well as rules that are
generally applicable within the network in order to keep it secure from external and internal
attacks.

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8. Designing the proposed secured network design
Figure 1: Proposed Secure Network
(Source: Created by author)

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Part 2
Scanning Server
TCP SYN scan
Sudo nmap –sS scanme.namp.org
Enable OS detection and version detection.
Quick scan
Scan a single port

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Scan a range of ports
Scan all ports
Answer to question 4

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Command used to scan server Sudo nmap scanme.namp.org
IP address of the server 45.32.33.156
Ports open in the server 22 – ssh
25 – smtp
30 - http
Sunning Web server Http Server, port 30
web server version in use is patched No
Answer to question 5
HTTP packets
Exclude HTTP packets

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