To understand firewalls, basic understanding of how networks
function is requisite. Deep down, how do the packets of information that you
send reach the intended receivers? How do the messages intended for you reach
you safely? And how does it all function like clockwork? Let’s understand the
basics of firewalls and see how a firewall secures the traffic in and out of a
network.
Consider this scenario for getting an understanding of how
firewalls work. Say, you open up your browser to book a flight ticket for your
upcoming vacation, and your computer is conveniently insecure without a
firewall. Let’s say you come across an intriguing email that gives an offer you
can’t refuse. You open the email and click a link, and bam! An unwanted piece
of spyware is installed on your system. The spyware then proceeds to sit on
your system tray, hidden from your eyes, tracking the keystrokes you make,
reading the top-secret files you have, and looking for potentially rewarding
information, such as your credit card number.
The spyware, once it obtains the necessary information,
opens a tunnel to its creator, passing all the relevant information it
receives—silently. You may realize that someone else has your bank passwords or
your credit card number after you get your hands on the next statement, and by
then it will all be too late.
The role of a firewall is
to essentially block this kind of anonymous installations, tracking, and hacking
attacks.
The firewall protects your computer from hackers,
malware, and viruses. It allows only the benign traffic to pass through,
protecting the important data you have on your computer.
So, how does a firewall work? How tangible is it really is?
For a home computer, a firewall can be as intangible as any regular software
application. It resides on your hard drive and runs on your RAM, providing
real-time protection. However, there are also hardware firewalls.
Hardware firewalls come packed in broadband routers similar
to the one you use at your home. Hardware firewalls are generally used by
businesses and are effective out of the box. They are used to protect the
entire range of machines in a network. Software firewalls on the other hand are
mostly intended for individual and home users who do not have a large network to
protect.
Unified Threat Management
Unified threat management (UTM) is a new paradigm in
enterprise security that includes all products required for the security of a
network—intrusion prevention, antivirus, anti-spam, load balancing, content
filtering, etc. A UTM solution is essential for businesses of all kinds that
deal with data and computers. There are a large number of UTM solution
providers in the market, including Cisco Systems, WatchGuard, Cyberoam, Fortinet,
Sophos, Comodo, among others.
What Qualifies as Unsafe Traffic?
As we have gained an understanding of what a firewall
essentially is, let’s delve into what is typically unsafe traffic and how you
may come across it.
The threats you may come across while you’re online can be
in ten prominent forms as detailed in the table below.
|
Threat
|
Key
Characteristics
|
Sources
|
|
Virus
|
Copying itself by attaching itself to applications
|
File downloads, email attachments, USB drives,
CDs, DVDs
|
|
Worm
|
Standalone
program, spreading itself through emails and other means
|
USB
drives, rogue websites
|
|
Trojan
|
Non-self-replicating; carries out specific actions
and opens a backdoor to the creator
|
Rogue websites, file downloads, USB drives, emails
|
|
Spyware
|
System
monitoring, data gathering, keylogging, installs by deceiving the user or
through software vulnerabilities
|
File
downloads, advertisements, emails, rogue websites
|
|
Adware
|
Automatically displays vexing advertisements
|
Through software downloads, cloud services, mobile
apps, etc.
|
|
Rogue Security Software
|
Masquerades
as genuine security software and compromises the system, demands ransom for
rectifying the damages caused
|
Social
engineering, advertisements, frauds, rogue websites
|
|
Spam
|
Unsolicited & undesired data in large
quantities, acts in denial of service
|
Email, web traffic
|
|
Phishing
|
Attempts
to fool users into providing sensitive information by mimicking genuine
services
|
Email,
websites
|
|
Pharming |
Redirects genuine traffic to rogue sites to steal
sensitive information
|
Hacking, hijacking genuine domains and ISPs
|
|
Keyloggers
|
Resides
in the system as a hidden process and listens to the keystrokes, transmits
logged keys to the creator
|
Rogue
applications, downloads, websites
|
As we understand what qualifies as security threats, it’s
your primary responsibility to steer clear of such threats. A firewall is an
essential piece of software that will help you fight all of these threats. You
need to install a good firewall on your computer in order to secure it
perfectly. If you want to know about the best of firewalls, please visit a
security software review service such as AV-Test.org.
Keep your firewall updated by connecting to the Internet and
turning the firewall’s auto-update function on. The automatic update will keep
your security software up to date on the latest threats and will continue to
protect your computer.