What is Computer Firewall, and why do you need one?
A Firewall is a computer program that monitors the flow of information from the Internet to your computer. There are two different types of firewall available for you to use - Hardware Firewalls and Software Firewalls.
Hardware Firewall
A Hardware Firewall is a physical piece of equipment that sits between the Internet and your computer. An example of a hardware firewall is a broadband router, a common form of Internet connection. The benefit of using a hardware firewall, is that it has the ability to protect multiple computer systems that are connected to it at the same time. This makes it an effective firewall for use in businesses that have multiple computers connected to the Internet, as well as in homes that have more than one computer system.
However, it is not sufficient to have only the hardware firewall, because router-based firewalls only provide protection from computers on the Internet, not from computers on your home network. For example, if a mobile computer or guest computer connects to some other network, becomes infected with a computer worm, and then connects to your home network, your router-based firewall won't be able to prevent the spread of the worm. Therefore, a firewall running on each computer on your network can help control the spread of worms.
Note that running more than one firewall program on your computer at the same time could cause conflicts. It's best to just use one firewall program, in addition to a router-based firewall.
Software Firewall
Software Firewalls work in the same way as a hardware firewall, by monitoring and blocking information that comes to your computer via the Internet, however software firewalls must be installed as a program on your computer. These software firewalls can either be installed from a computer disk that you have purchased, or downloaded over the Internet. Software firewalls are the most common type of firewall. Programs such as Norton 360, Norton Internet Security, ESET Smart Security, and Kaspersky Internet Security all have a firewall bundled within them.
If you have Windows Operating System, the Firewall program is installed already by default. It is also set to active operations from the beginning. To make sure it hasn't been turned off, follow these steps:
- Open Windows Firewall by clicking the Start button, and then clicking Control Panel. In the search box, type firewall, and then click Windows Firewall.
- In the left pane, click Turn Windows Firewall on or off. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
- Below each network location type, click Turn on Windows Firewall, and then click OK. We recommend that you turn on the firewall for all network location types.
What a Firewall does?
Regardless of what type of firewall you choose to use, having one on your computer is a really good idea. A firewall helps to prevent computer hackers from accessing your computer through the Internet, and stealing sensitive information or infecting your computer system with some form of computer virus. A hacker can gain access to your system by “back doors” or open ports that connect your computer to the Internet. With a firewall in place these ports are blocked from inbound traffic, effectively closing the door in the hackers face.
Of course, damage can also be done to your computer from outbound traffic as well. Say for instance a hacker was able to slip by you with a Trojan, virus, spyware or phishing scheme that went undetected. The next time you booted up your computer and connected to the Internet, information on your computer could be sent out to the hacker. Many firewalls also block outbound traffic that will help prevent this from happening.
There are basically two ways that Firewalls work. Generally, data that comes in is analyzed by the firewall to determine the IP address it is coming from and the content that it contains. The firewall system then checks to see if this information is compliant with rules that you are able to configure. It can also analyze information at the application level. The firewall program will determine whether or not the application should be able to send or receive data through the port you are connected by.
Firewall programs are extremely important to the protection of not only your computer system, but you personal information as well. Many anti-virus programs come with firewall protection. Firewall protection should be considered an essential part of any computer's security strategy.
What are some of the things that a firewall can't prevent?
- E‑mail viruses
E‑mail viruses are attached to e‑mail messages. A firewall can't determine the contents of e‑mail messages, so it can't protect you from these types of viruses. You should use an antivirus program to scan and delete suspicious attachments from an e‑mail message before you open it. Even when you have an antivirus program, you should not open an e‑mail attachment if you're not positive it's safe.
- Phishing scams
Phishing is a technique used to trick computer users into revealing personal or financial information, such as a bank account password. A common online phishing scam starts with an e‑mail message that appears to come from a trusted source, but actually directs recipients to provide information to a fraudulent website. Firewalls can't determine the contents of e‑mail messages, so they can't protect you from this type of attack.
Should you replace Windows Firewall?
If you are obsessed with your computer security, you may consider replacing our Windows Firewall with alternative solutions. Free and commercial software is available on the market for your evaluation. The default Windows firewall (Internet Connection Firewall) that is installed on Windows operating system has limitation of security protection or less user-friendly compares to third party firewall software.
Two major disadvantages to using default Windows firewall:
1. Default Windows Firewall does not restrict outgoing traffic from your computer or restrict applications from using your Internet connection. This means that if have a virus, Internet connection firewall will allow your applications to send data to the Internet without your permission.
2. When you boot your computer, Windows will enable your Internet connection before it enables the built-in firewall. This means that if someone attempts to hack your computer or port scan you while your computer is booting, your computer will be available on the Internet before the firewall starts up. This creates a limited opportunity for your computer to be hacked. Though this risk is mitigated by the short length of time between your Internet connection being active and the firewall starting, it is still a risk to take into consideration.
Alternatives for Windows Firewall
While we do not target in this post reviewing the available freeware firewall solutions, I would like to propose for your consideration the following utilities:
- Comodo Internet Security, the latest Comodo Internet security that combines firewall and antivirus software can secure your system against internal attacks such as Trojans, viruses, malicious software and external attacks by hackers. Meanwhile, Comodo Internet Security run a multi-layered security application that protects you against identity theft hackers, Trojans, scripts and other unknown threats. Plus more, the Comodo firewall easy to understand and configure.
- ZoneAlarm firewall is designed to protect your cable or DSL-connected computer against unauthorized access by hackers, hijackers and malicious software. It also blocks threats already on your pc from communicating with the malefactor or a third party so that hackers can’t gain access to your computer or personal data.
- Private Firewall integrated desktop firewall and multi-layered intrusion prevention technology to protect your computer. This free private firewall delivers signature-less, real-time protection from known or new spyware, viruses, hacking techniques, and other intrusions on Windows desktops and servers. Meanwhile, it also offers network security features like port tracking, URL and packet filtering and application/system behavior modeling and anomaly detection components to protect both inbound and outbound traffics of user PCs.
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