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Wireless Network Threats: Firewall Countermeasures
Enebeli Edwin Ndudi
Course: MSC. Computer Science (Software Engineering)
Faculty of Computer Science & IT, Universiti Selangor, 40000 Shah Alam, Malaysia
Abstract
Ever since wireless network security threat issues arises, several countermeasures
have been adopted such as the use of ant-viruses software, network firewall and other
countermeasure approach to tackle threats issues across computer network. This
paper is focusing on the use of firewall as a method of dealing with network security
challenges. Many internet users today doesn’t know how firewalls works; it benefits,
drawback, and it categories. Sometimes, when system firewall block some suspicious
webpage content and application access users were always optioned to turn off
firewalls to grant access to those website or application without that they are threats
to peoples information’s. This paper is creating awareness about threats on wireless
network and how to avoid them by using network firewalls. The main objective of this
research is to demonstrate wireless network security threat countermeasures using
firewall, also to determine how firewall works. The advantages and disadvantages of
firewall are to be determined in this paper in order to foresee why or not a firewall
should be a network threat countermeasure. These papers also propose quite number
of solutions for dealing with those threats associated with warless network.
Keywords: Wireless Network Security, Threats Countermeasures, Network Firewalls.
1.0 Introduction process of introducing cables into
buildings or as a connection between
Wireless networks are computer
different equipment locations. Wireless
networks that are not connected by
networks use radio waves to connect
cables of any type. Wireless network
devices such as laptops to the Internet,
enables enterprises to avoid the costly
the business network and applications.
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When laptops are connected to Wi-Fi wired/wireless network by describing it
hot spots in public places, the advantages and disadvantages in order
connection is established to that to see if firewall is a good network
business’s wireless network. threats approach of dealing with
network security challenges. A firewall
However, wireless technology also
is something that the user of the
creates new threats and alters the
computer is responsible for checking
existing information security risk
and installing. The security levels
profile. For example, because
provided by the firewall can be altered
communications takes place "through
just as any other control function can
the air" using radio frequencies, the risk
be altered. Security experts say that the
of interception is greater than with
best way to stay safe online is to only
wired networks. If the message is not
visit websites that one trust or that you
encrypted, or encrypted with a weak
are sure are secure but doesn’t
algorithm, the attacker can read it,
guarantee safety .
thereby compromising confidentiality.
Although wireless networking alters the A. Wireless Network Security
risks associated with various threats to
Secured network has now become a
security, the overall security objectives
need of any organization. The security
remain the same as with wired
threats are multiplying everyday and
networks: preserving confidentiality,
making high speed wired and wireless
ensuring integrity, and maintaining
network and internet services, insecure
availability of the information and
and undermining network reliability.
information systems. The
This day’s security measures works
disadvantages of using a wireless
more importantly towards fulfilling the
network are: Security, Range,
cutting edge demands of today’s
Reliability, and Speed. Network
growing industries (Pandey, 2011). The
firewall has been one of network
need is also induced in to the areas like
security threat countermeasure, the aim
defence, where secure and
of this paper is to scrutinize how
authenticated access of resources are
firewall counter security threat in
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the key issues related to information through wide area networks and the
security. Internet. A firewall protects computers
by acting as a gate through which all
B. What is Firewall?
data must pass. By blocking certain
A firewall is a virtual wall/gateway in kinds of traffic, the firewall protects
other words software, which is located computers or network from
between internal and external networks. unauthorized users and safeguards data
Firewalls can be an effective means of from attack. Setting up a firewall has
protecting an intranet from network- distinct advantages and disadvantages.
based security threads that come from Most computer operating system comes
outside networks while in the mean with firewall installed on it, and can be
time providing access to outside world purchased and stored installed.
2.0 Why Firewalls Are Necessary
A vast number of local intranets form intranet and internet is essential and
the global internet, which allows one to absolutely necessary. On the internet it
obtain from as well as to provide is a virtual world, but it is just like the
information to the whole world. Since real world, where be malicious users
the internet access provides such who snoop on other’s valuable
benefits to any personal and information or even some criminals
organizations, the connection between who enjoy bringing down other
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systems (Wang, 2004). Security is an Denial-of-service attacks can be
important issue, so a virtual firewall implemented using common internet
needs to be built up around internal protocols, such as TCP and ICMP.
network to protect both physical and
3.3 Source Routed Traffic
abstract resources in the intranet.
Usually a network packet itself only
3.0 Types of Attack
says where it wants to go, and nothing
In order to understand the firewalls about how it expects to get there. But
implementation, its important to sometime the sender of a packet can
understand the most common methods include information in the packet that
of attacking wireless network. Some of tells the route the packet should take to
them are listed below. get to its destination. This is called
source routing. This can be used to
3.1 IP Spoofing Attacks
bypass the security measures.
In this type of attack, an attacker
3.4 Tiny fragment attacks
outside the local intranet may pretend
to be a trusted computer either by using Here an attacker creates extremely
an IP address that is within the range of small packet fragments by taking
IP addresses for the local network or by advantage of the IP fragmentation
using an authorized external IP address option. The attacker hopes that only the
that has authorized access to specified first fragment is examined by the
resources on the local network. security measures and the others can
pass through safely.
3.2 Denial of Service Attacks
Tiny fragment attack is designed to fool
The purpose of these attacks is just to
a firewall or packet filter by creating an
make a service unavailable for normal
initial fragment that is very small. It is
use by flooding the network with
so small that it does not contain TCP
undesired, and often useless, network
port number; instead the TCP port
packets to exhaust the resource
number follows in the second packet.
limitation on the network or within an
operating system or application.
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4.0 Threat Countermeasures: i.Very little data is analyzed and
Firewalls logged; filtering firewalls take less
CPU and create less latency in your
Firewall simply blocks any
network.
unauthorized communication between
internal and external networks. ii. The user does not have to consider
Basically, there are three basic types of blocking rules in their applications, so
firewalls which include packet-filtering filtering firewalls are more transparent
firewalls, application- level gateway to the user.
and circuit-level gateway.
4.1.2 Disadvantages of Packet
4.1.0 Packet-filtering firewalls Filtering Firewalls
A Packet Filtering firewalls is normally i. Whenever some rules are based on IP
implemented by configuring a router to numbers and the network is using
filter packets going in both directions. dynamic IP assignment, this can be a
It works at the IP network layer. A problem, because the dynamic IP is
packet filtering router usually can filter changed sometimes, IP address cannot
(i.e. block) IP packets based on some or be specified to be filtered.
all of the following fields: Source IP
ii. Packet filtering rules are complex to
address, Destination IP address,
specify and usually no testing facility
TCP/UDP source port, and TCP/UDP
exists for verifying the correctness of
destination port. The packet filter is
the rules
typically set up as a list of rules based
on matches to IP address or TCP/UDP 4.2.0 Application-Level Gateway
port number to block connections from
Application-level gateways firewalls,
or to specific hosts or networks, and to
also called proxy-based firewalls,
block connections to specific ports.
operate at the application level. They
4.1.1 Advantages of Packet Filtering are usually implemented by
Firewalls implementing separate proxy
application for each service. They
provide all the basic proxy features and
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also provide extensive packet analysis. ii. The application commands are
The client needs to provide valid user analyzed inside the payload portion of
ID and authentication information to the data packets.
the proxy server in order to
4.2.2 Disadvantages of Application-
communicate with the destination
Level Gateways Firewalls
service. In effect, the proxy establishes
the connection with the destination i. Application-level gateways firewalls
behind the firewall and acts on behalf is slower than packet filters
of the client, hiding and protecting ii. Needs the internal client to know
about them.
individual computers on the network
iii. In Application-level gateways
behind the firewall. Since all firewalls every possible type of
communication is conducted through connection cannot be supported
the proxy server, computers behind the 4.3.0 Circuit-Level Gateway
firewall are protected. A typical Firewalls
application-level gateway can provide
Circuit level gateways work at the
proxy services for applications and
session layer of the OSI model, or as a
protocols like Telnet, FTP (file
"shim-layer" between the application
transfers), HTTP (Web services), and
layer and the transport layer of the
SMTP (e-mail).
TCP/IP stack. They monitor TCP
4.2.1 Advantages of Application- handshaking between packets to
Level Gateways Firewalls determine whether a requested session
is legitimate. Information passed to a
i. Direct connections between internal
remote computer through a circuit level
and external hosts are disallowed and
gateway appears to have originated
unauthorized access is restricted.
from the gateway. Circuit-Level
ii. In Application-level gateways Firewalls applications represent the
firewalls, user-level authentication is technology of next to first generation
supported. .Firewall technology supervise TCP
handshaking among packets to confirm
a session is genuine. Firewall traffic is
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clean based on particular session rules ii. Circuit-level gateways firewall is
and may be controlled to acknowledged simpler to implement
computers only. Circuit-level firewalls
4.3.2 Disadvantages of Circuit
conceal the network itself from the
Level-Gateways
external, which is helpful for
contradicting access to impostors. But i. In circuit level-gateways, an active
Circuit-Level Firewalls don't clean content cannot be scanned or
entity packets. This is useful for hiding disallowed commands.
information about protected networks.
ii. Circuit level-gateways can only
Circuit level gateways are relatively
handle TCP connections and new
inexpensive and have the advantage of
extensions is proposed for UDP
hiding information about the private
network they protect. On the other 5.0 Firewall Design Principles
hand, they do not filter individual
To design a firewall for a network,
packets.
briefly there are several aspects needed
4.3.1 Advantages of Circuit-Level to be considered:
Gateways
i. The attacks you intend to deal with:
i. One of the best advantages of circuit- Various threats a lied across wireless
level gateways firewall is the private network, its highly recomposed that
network data hiding whole information flow should be
accessed to find which one that requires
ii. Avoidance of filtering individual
urgent actions and which firewall
packets
should be used.
iii. Flexible in developing address
ii. The services you intend to offer to
schemes
external networks from your protected
i. Circuit-level gateways firewall don’t network.
need a separate proxy server for each
iii. The services you intend to request
application
from external networks via your
protected network.
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iv. Evaluate the available firewall Packet-filtering firewalls works at the
products. Firewalls variety should be IP network layer, application-level
evaluated to determine their network gateway operates at the application
threat countermeasure suitability. layer why the Circuit level gateways
work at the session layer. In the recent
Generally, if cost, speed, flexibility,
years, studies have shown that
and ease of use are strong motivators, a
application layer has been the popular
packet-filtering firewall is the best
route attacker’s uses to launch an attack
choice. But because each type of
on a vulnerable computer wireless
implementation has its own
network. Therefore, application-level
disadvantage and advantage, so if you
gateways are highly recommended to
can afford it, it is better to have multi-
counter threats lies on application level
level firewall architecture to achieve
of OSI model. In packet-filtering
the securest network.
firewalls, the packet filter is set up as a
5.0 Discussion list of protocols based on matches to IP
address or TCP/UDP port number to
The security levels provided by
block connections from or to specific
network firewalls can be altered just as
hosts or networks, and to block
any other control function can be
connections to specific ports;
altered. Setting up or installing an
application-level gateway are usually
Internet firewall is intentionally very
implemented by initiating a separate
simple. Most computers come with a
proxy application for each service.
firewall program. The only thing that
the user needs to do is set the settings Application-level gateway firewalls
for the firewall. Circuit-level gateways purvey all the basic proxy features and
firewall is a type of firewalls that is also provide an extensive packet
very simple to implement comparing to analysis. In this type of firewall, client
other types but can only handle TCP needs to provide valid user identity and
connections why new extensions authentication information to the proxy
proposed is for UDP. server so that it can communicate with
the destination service. Circle-level
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gateway firewall monitors TCP use a variety of techniques to protect
handshaking between packets in order against attacks. As proxy servers,
to determine if the requested session is firewalls mask IP address and limit
valid. All the information’s waded to a traffic types. External computers
remote computer through a circuit level communicate with them, instead. As
gateway appears to have originated circuit-level gateways, firewalls limit
from the gateway connections to trusted networks only.
Packet-filtering firewalls examine each
7.0 Conclusion
packet, rejecting those that fail security
Wireless networking provides several testing. This paper has successfully
opportunities to increase productivity scrutinized how works firewalls in
and reduce costs. It also alters an order guarantee safety of information
organization’s overall computer and blocking of unwarranted access to
security risk profile. Although it is a given computer. The use of firewall
impossible to totally eradicate or threat countermeasures should be
eliminate all risks associated with considered in every Local Area
wireless network, but is possible to Network (LAN) and Wide Area
achieve a reasonable degree of overall Network (WAN) infrastructure so that
security by adopting firewall network security issues would be
countermeasures techniques. Firewalls solved to a certain reasonable level.
8.0 References threats and countermeasures.
International Journal of Multimedia
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and Ubiquitous Engineering, 3(3), 1-3.
C. H., & Kim, T. H. (2008). Wireless
Retrieved from http://www.sersc.org
network security: Vulnerabilities,
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[2] Makki, S. K., Reiher , P., Makki , [4] Pandey, S. (2011). Modern network
K., Pissinou , N., & Makki, S. (2007). security: Issues and challenges.
Mobile and wireless network security International Journal of Engineering
and privacy. (1 ed., Vol. 1, p. 6). New Science and Technology, 3(5), 1-7.
York: Springer US. Retrieved from Retrieved from http://www.ijest.info/
http://www.springer.com
[5] Wang, H. (2004). Network firewall. 1(1), 1-
[3] Sunday, N. A. (2008). Wireless 7. Retrieved from
http://www.learningace.com/
local area network (wlan): Security risk
assessment and countermeasures . 1(1),
3. Retrieved from http://www.bth.se
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