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.