How to Turn on a Firewall

A firewall is designed to prevent unauthorized access to a computer system. A firewall is also used to encrypt and decrypt computer traffic between computers on a network. There are many different types of firewall techniques. A circuit level gateway applies security mechanisms to check the sender once and allow that particular user to have access without further checking. An application gateway applies security to applications, which is effective, but hurts performance. The proxy server checks all messages coming in and out. And a packet filter works as a proxy but is run by a set of user-defined rules. Firewalls can be found in networks, through third party software, and preinstalled in operating systems. This article covers the operating systems aspect of turning on firewalls.

Difficulty: Easy

Instructions

To turn on the Windows Firewall for Windows XP

1. Click the "Start" button.

2. Click "Run."

3. Type "firewall.cpl," and click "OK."

4. Select the "General" tab. Click the "On" radio button.

5. Click "OK."

To turn on the Windows Firewall for Windows Vista

6. Click the "Start" button.

7. Type "firewall.cpl." The Windows Firewall window will open.

8. Select "Change Settings." The Windows Firewall Settings window will open.

9. Click the "On" radio button.

10. Click "OK."