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How do I configure ZoneAlarm (personal PC firewall software)?

Zone Alarm is available to download from http://www.zonealarm.com/ and is only free for personal use and not-for-profit use.

Given the Information Strategy and Services Syndicate notice that 'CUDN-connected computers must support the ICMP Echo (ping) function' the default configuration of ZoneAlarm needs to be changed to allow a response to ping at least from the Trusted Subnet 131.111.12.0/24 if a machine with ZoneAlarm gets connected to the CUDN.

NOTE: Please see "The Home User Guide to PC Security" and "What should I do when I connect my personal Windows computer to the network?" for further information on PC security.

To allow a response to ping from the Trusted Subnet 131.111.12.0/24:

Version 3 of ZoneAlarm

  • Double-click the ZoneAlarm icon in the System Tray
  • Click on Firewall in the left-hand toolbar area
    Click on the Zones tab in the top right of the dialogue box. You should see your own computer's IP Address listed as in the Trusted Zone. You need the following as well...
  • Click on Add>> button and select Subnet
  • In the Local Zone Properties dialogue box, click Add >>, Subnet...
  • In the Trusted Zone specify:
    • IP Address 131.111.12.0
    • Subnet Mask 255.255.255.0
    • Description CS Trusted
  • Click OK

It is suggested that you then also add the Computing Service internal network. 131.111.10.0/23. If you choose to do so:

  • Click Add >>, Subnet
  • In the Trusted Zone specify
    • IP Address 131.111.10.0
    • Subnet Mask 255.255.254.0
    • Description CS Internal
  • Click OK

Then finish off:

  • Click Apply to reconfigure ZoneAlarm
  • Exit ZoneAlarm but leave it running.

Version 2 of ZoneAlarm

  • Double-click the ZoneAlarm icon in the System Tray
  • Click the Security button
    Local should be set to Medium which 'Leaves your computer and servers visible to the local network'
  • Click Advanced
  • In the Local Zone Properties dialogue box, click Add >>, Subnet...
  • Specify:
    • Description Trusted
    • IP Address 131.111.12.0
    • Subnet Mask 255.255.255.0
  • Click OK

It is suggested that you then also add the Computing Service internal network. 131.111.10.0/23. If you choose to do so:

  • Click Add >>, Subnet...
  • Specify
    • Description CS
    • IP Address 131.111.10.0
    • Subnet Mask 255.255.254.0
  • Click OK

Then finish off:

  • Click OK to close the Local Zone Propertiesdialogue box.
  • Exit ZoneAlarm but leave it running.

The title of this document is: How do I configure ZoneAlarm (personal PC firewall software)?
URL: http://www.cam.ac.uk/cs/docs/faq/m3.html

Last updated: 15 January 2003