Windows XP provides you a feature to enable or disable network connection. This is especially useful for you to disconnect your network connection without physically unplug network cable from network card. In wireless network, this disable feature will disconnect you from wireless network till you re-enable it again.
Disabling unused network connection will also improve your computer security. This is especially important if your Windows system is not updated frequently and have no firewall or antivirus software installed.
1) Go to Start--> and click on Control Panel.
2) Control Panel window will appear--> Double click on Network Connections.
3) Network Connections window will appear. Right click correct Local Area Connection by identifying the network card and type. If the connection is currently enabled--> the first option in this menu will be Disable. Otherwise, the option will be Enable.
Click on the Enable/Disable option to enable/disable your network connection.