Firewall and antivirus software both help protect computer systems, but they do so in different ways. A firewall is hardware and software that monitors network traffic and restricts unauthorized access between a private network and the internet. An antivirus software scans for and removes malware like viruses, worms, and trojans that could already be inside a computer system. While firewalls prevent external threats, antivirus software addresses internal threats, and both work together to provide layered security protection.

1. Firewall, Antivirus
Software
Dr SAJEENA S.

2. • Preventive
Measures-
Firewall,
Antivirus
Software
• In the realm of cybersecurity,
Antivirus and Firewall are two
words used interchangeably.
Both are used to protect the
hardware and software of a
computer system.

3. Firewall
• A firewall is a hardware and software-based
security system designed to protect and monitor
both private internet network and a computer
system. Firewall provides a first line of defense for
the resource in an e-commerce system. It defends
against unauthorized access to systems over the
internet.
• Firewall is defined as “a software or hardware-
software combination that filters communication
packets and prevents some malicious packets from
entering the network, based on a security policy.”
Most organizations place a firewall at the internet
entry point of their networks. The firewall provides
a defense between a network and the internet.

7. Firewalls
operate on
the
following
principles.
All traffic from inside to outside
and from outside to inside the
network must pass through it.
Only authorized traffic, as defined
by the local security policy, is
allowed to pass through it.
The firewall itself is immune to
penetration.

8. • Types of Firewalls
• Proxy-based firewalls: These are proxies that
sit in between clients and servers. Clients
connect to the firewall, and the firewall
inspects the outgoing packets, after which it
will create a connection to the intended
recipient (the web server). Similarly, when
the web server attempts to send a response
to the client, the firewall will intercept that
request, inspect the packets, and then
deliver that response in a separate
connection between the firewall and the
client. A proxy-based firewall effectively
prevents a direct connection between the
client and server.

9. • Stateful firewalls: A stateful application is
one which saves data from previous events
and interactions. A stateful firewall saves
information regarding open connections and
uses this information to analyze incoming
and outgoing traffic, rather than inspecting
each packet. Stateful firewalls rely on a lot of
contexts when making decisions. Stateful
firewalls can also protect ports by keeping
them all closed unless incoming packets
request access to a specific port.

10. Next-Generation Firewalls (NGFW): These are
firewalls that have the capabilities of traditional
firewalls but also employ a host of added features to
address threats on other layers of the Open Systems
Interconnection (OSI) Model.
Some NGFW-specific features include: Deep packet
inspection (DPI), Application awareness, Identity
awareness and Sandboxing.

11. Web Application Firewalls (WAF): WAFs help to protect web applications
from malicious users. A WAF helps protect web applications by filtering
and monitoring HTTP traffic between a web application and the Internet.
Packet Filter: It is a network security technique that is used to control
data flow to and from a network.
Gateway Server: Gateway servers is a networking hardware or network
node which connects the two disparate network to communicate with
each other.

12. •Usefulness
of Firewall
• A firewall can monitor all the incoming
traffic. A two – way firewall can monitor the
exiting data as well and can encrypt it too.
• A firewall limits the Trojan horse from
latching onto your computer files and does
damage to the entire network.
• It stops hackers from entering your
network.
• It reduces the risk of keylogging. Keylogging
is a computer program that records every
keystroke made by a computer user to gain
fraudulent access to passwords and other
confidential information.

13. • Functions of Firewall
• The basic function of a firewall is to analyse any incoming files from the internet
or other computers before accepting the files to download.
• Block viruses or other malicious files before they reach your computer.
• Firewalls prevent malicious programs from accessing and damaging your
computer system.
• Block unsolicited communication between your computer and other computers
outside the organization.
• Protect your computer from hackers. In e-commerce environment, many hackers
attempt to gain access to your computer without your consent. A firewall can
block them before they install on your computer.
• Control outbound connections from your computer to prevent connection to
unauthorized outside nodes.
• Track and record inbound and outbound connections.

14. Limitations of Firewall
• Firewalls may potentially interfere with the operation of
some programs that access internet. It may block some
communications required for running a program.
• Firewall software can help block viruses and malware, but it
cannot remove viruses and other malware that has been
loaded onto your computer. In other words, firewall is not an
alternative to using an antivirus program, but an additional
level of protection.
• Firewalls can control the traffic between the computer and
the internet, but they are incapable to recognise any attack
against the computer from within.

15. • Antivirus Software • The most common method available
to protect the computer system
from virus attack is installing
antivirus program. Antivirus
software is a program that helps to
prevent computer threats such as
viruses, hackers and different types
of malware threats. It scans every
file which comes through the
internet, USB devices or external
hard disk to your computer and
helps to protect your computer from
virus attack.

16. • Virus protection software (antivirus) ensures the protection of
computer system from the constant threat of different types
of viruses. There are several companies that build and offer
antivirus software. Popular antiviruses are Norton Antivirus,
Kaspersky, Avira, Quick Heal, AVG, McFee, Bitdefender, Panda,
BullGuard etc.

17. The following are the basic functions offered by all antivirus programs.
Ensures Security: Virus protection software scans a computer, create
firewalls, prevents harmful virus attacks and ensures a computer’s overall
security.
Prevents Online Threats: While surfing, downloading or working online,
the antivirus software prevents threats posed by malicious virus attacks
through e-mail attachments, spurious websites, and other proxy/ third
party freeware downloads.
Protects Critical Data: The antivirus software protects critical files,
documents, presentation and photos stored on a computer from being
infected or damaged through virus attacks or virus downloads during
online activities.
Scanning Alerts: Antivirus software alerts users about scanning a specific
file, drive or pen drive, at any time.
Facilitates Timely Updates: Many virus protection programs ensure the
computer’s protection by automatically updating its security features.

18. • Benefits of Antivirus Software
• Antivirus solutions protect more than just laptops, office computers, smartphones and
tablets. They protect precious memories, music and photo libraries, and important
documents from destruction by malware.
• Modern antivirus solutions are capable of:
• Detecting, blocking, and removing viruses, malware, and ransomware
• Preventing identity theft and block phishing and fraud
• Warning about dangerous websites and links before you click
• Scanning the Dark Web to find if an email address has been compromised
• Keeping online accounts protected with secure password encryption
• Providing simple training to teach you and your family how to be even safer online
• Tuning up your computer to keep it running smoothly, just like new

19. • There are fundamental differences between a
firewall and antivirus software. For one, a
firewall is a hardware and software-based
security system designed to protect and monitor
both a private internet network and a computer
system. While antivirus is a software program
that detects and eliminates any threats that will
destroy a computer system.

20. Differences between Firewall and Antivirus
Firewall Antivirus
A firewall is a security network designed to protect
computer systems and networks from malicious attacks.
Antivirus is a software utility program designed to protect a
system from internal attacks from viruses, trojan horse,
spyware etc
The general term used for a firewall is “packet filter”
because it filters any incoming data packets for suspicious
contents.
Antivirus identifies and corrects any weaknesses found in
the computer system.
The main purpose of a firewall is to monitor network traffic
and restrict any unauthorized entry
The main function of an antivirus is to scan, detect, prevent
and remove any existential threat to the computer system
A firewall works at a network protocol level to safeguard
against any unwanted intrusion
An antivirus will only scan for any harmful programs that are
present in the system such as viruses, worms, Trojans etc
One of the limitations of a firewall is that it cannot block
any internal attacks and also those attacks that bypass its
network coverage
One of the limitations of an antivirus is that it cannot check
read-only files.
DEC SEAL was the first commercially viable firewall program
that came out in 1992. Its creation was spearheaded by
American computer scientists Brian Reed and Jeff Mogul.
The first documented removal of a computer virus was by an
actual antivirus software was in 1987 when a German
computer security expert, Bernard Robert Fix, created a
programme to remove a virus that had infected files in a
DOS-based system