Windows XP includes ICF, which allows you to protect a single computer, or the shared Internet connection (ICS) computer, if you are not already protected via a proxy or firewall.

To enable / disable ICF:

  1. Control Panel / Network Connections.

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  3. Press the Dial-up, LAN or High-Speed Internet connection that you want to protect press Change settings of this connection (under Network Tasks).
     
  4. Select the Advanced tab. Check or clear:
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