Internet Security Part 1: Firewall

May 24, 2008 | Filed Under Internet

Connecting to the Internet has many benefits and advantages. Much of what I have learned, I learned through Google and Internet searches. And it is true for most people, like you and me.

Internet image The fact, however, that your computer is connected to the Internet, makes it always at risk to intrusion and virus attacks. There are people who spend their time in looking for ways to gain access and attack other unsuspecting users. For your safety, you must always ensure that a firewall is running before going online.

Not implementing a firewall makes your computer-stored personal information, like bank account numbers, credit card data, tax information, and so on, accessible to attackers. Think of the firewall as a huge, tough-looking bouncer who stops anyone coming into your computer if they’re not on the guest list.

What is a Firewall?

Source: Wikipedia

A firewall is a device or set of devices configured to permit, deny, encrypt, or proxy all computer traffic between different security domains based upon a set of rules and other criteria.

What a firewall does:

Basically a firewall protects you and your computer data against a number of different online threats. A firewall protects you from hackers, “worms” that spread from computer to computer over the internet and outgoing traffic that might originate from a virus or a Trojan infection.

Source: Wikipedia

“A firewall is a dedicated appliance, or software running on another computer, which inspects network traffic passing through it, and denies or permits passage based on a set of rules.
A firewall’s basic task is to regulate some of the flow of traffic between computer networks of different trust levels. Typical examples are the Internet which is a zone with no trust and an internal network which is a zone of higher trust. A zone with an intermediate trust level, situated between the Internet and a trusted internal network, is often referred to as a “perimeter network” or Demilitarized zone (DMZ).

A firewall’s function within a network is similar to firewalls with fire doors in building construction. In the former case, it is used to prevent network intrusion to the private network. In the latter case, it is intended to contain and delay structural fire from spreading to adjacent structures.

Without proper configuration, a firewall can often become worthless. Standard security practices dictate a “default-deny” firewall ruleset, in which the only network connections which are allowed are the ones that have been explicitly allowed. Unfortunately, such a configuration requires detailed understanding of the network applications and endpoints required for the organization’s day-to-day operation. Many businesses lack such understanding, and therefore implement a “default-allow” ruleset, in which all traffic is allowed unless it has been specifically blocked. This configuration makes inadvertent network connections and system compromise much more likely.”

What a firewall DOESN’T do

A firewall, on its own is not enough to guarantee online security. Think of a firewall as your gate. It is your first line of defense before someone uninvited breaks in into your home.

A firewall provides minimal or zero protection:

If you allowed or permitted other computers to connect to yours.
If it the firewall is turned off or disabled
Against spyware and adwares.
If you or a virus has created a back door through the firewall
If a hacker has the password for the firewall
Against people with physical access to your computer or network.
Against malicious traffic that does not travel through the firewall (example: a poorly configured wireless network)
Against attacks after a network has been compromised.
Against traffic that appears to be legitimate.
Against spams and most viruses.
If the firewall has many exceptions or open ports.
Against any kind of fraud or criminal activity online.
If you have no computer and/or internet connection

A firewall on its own is not enough for complete online security.

Different Types of Firewall

Desktop/Software firewall

A desktop/software firewall is installed on a computer or network. Windows Firewall is a basic example of a desktop/software firewall. It comes with every Windows XP (SP2 and up) and Windows Vista.

Advantages of a desktop/software firewall:

Windows Firewall is free and included with Windows XP and Windows Vista
Free software firewalls are available for private use.
Commercial desktop firewalls often integrate well with other security products like virus scanners.
Easy to set up – no wiring or extra hardware.
If you use a laptop, a desktop firewall will protect you wherever you connect to the internet.

How to install a desktop firewall

Your choice of desktop firewall depends on whether or not you are running Windows XP or Vista and whether or not you want to buy a commercial firewall.

To turn on Windows Firewall in Windows Vista

Open Windows Firewall by clicking the Start button, clicking Control Panel, clicking Security, and then clicking Windows Firewall.
Click Turn Windows Firewall on or off. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
Click On (recommended), and then click OK.

If you want the firewall to block everything, including the programs selected on the Exceptions tab, select the Block all incoming connections check box.

How to Verify if you have Windows XP, XP SP1, or SP2

You can check the version of Windows by opening the Control Panel and double-clicking on System. When the System control panel appears, under the word “System” it will tell you what operating system you are running.

Enable Internet Connection Firewall in Windows XP or Windows XP SP1

To configure Internet Connection Firewall manually in Windows XP or Windows XP SP1:

Click Start, click Run, type control.exe netconnections, and then click OK.
Right-click the connection on which you would like to enable ICF, and then click Properties.
On the Advanced tab, click the box to select the option to Protect my computer or network.
If you want to enable the use of some applications and services through the firewall, you must enable them. To do this, click Settings, and then click to select the programs, protocols, and services that you want to enable for the ICF configuration.

Enable Windows Firewall in Windows XP Service Pack 2

Click Start, click Run, type Firewall.cpl, and then click OK.
On the General tab, click On (recommended), and then click OK.

You can check if your firewall is operational by opening the Control Panel and double-clicking on Security Centre. A green light and the word ‘on’ should appear next to Firewall.

You can make sure that your firewall is operational by opening the Security Center in the Control Panel . A green light and the word ‘on’ should appear next to ‘Firewall’.

Hardware Firewall

Hardware firewalls are often built into broadband routers.

Advantages of a hardware firewall:

Can protect all of the computers in a network.
Doesn’t affect computer speed and performance since it doesn’t run on your PC.
Can’t be easily disabled by malicious software, unlike software firewalls.

Disadvantages:

May require in-depth technical knowledge and skill before configuration and customization.
Hardware firewalls treat outgoing traffic from the local network as safe, which can be a hazard if malware, such as a worm, penetrates your network and attempts to connect to the Internet.

If you are planning to buy a router, it would be best to have one with firewall capability.

Commercial Firewall

A commercial firewall functions basically the same way as Windows Firewall. However, commercial firewalls generally provide extra protection and control. It’s also bundled with more information, guide, and help on how to configure it. Generally, commercial firewall manufacturers provide online help and technical assistance for its clients. Most security software companies sell a firewall as a standalone software package or as part of a security suite that includes other protection such as a virus scanner. Software updates and upgrades are provided by the manufacturer almost as soon as threats are discovered.

I will discuss more on Commercial Firewalls in the next article.

Submit and Share this Article! These icons link to social bookmarking sites where readers can share and discover new web pages.

Tags: amfufu, blogging, computer, firewall, hardware, income, information, Internet, internet security, LAN, network, online, software, technology, tips, tweaks, website

This Entry is Registered and Protected by:

Comments

3 Responses to “Internet Security Part 1: Firewall”

The Aries on May 25th, 2008 1:40 am

Nice post. Nice Information
Jonathan J on May 25th, 2008 4:10 pm

Pretty neat article! Keep em’ coming, they are quite interesting to read. Though I have my windows firewall turned off, it usually causes more trouble that it’s worth; from what I’ve experienced!
How to Add Digg to Blogs | amfufu.com on May 25th, 2008 6:13 pm

[...] copy the the Digg URL for the article you submitted. (example: Digg URL for my latest article Internet Security Part 1: Firewall is : http://digg.com/security/Internet_Security_Part_1_Firewall [...]