A. By default IPSec will use Kerberos V5 protocol for its authentication method however there are other options:

  • Windows 2000 Kerberos V5 protocol (the default)
  • Use a certificate from a selected certificate authority
  • Use a predefined string (a preshared key)

To modify an existing IPSec policy start the IP Security Policy MMC snap-in as seen in the previous FAQ and perform the following:

  1. Right click on the policy and select Properties from the context menu
  2. Select one of the security rules you wish to change the authentication method for and click Edit
    Click here to view image
  3. Select the 'Authentication Methods' tab. The current authentication method will be shown, e.g. Kerberosby default. Select it and click Edit
  4. Select the preferred authentication method
  5. Click Apply then Close
  6. Close all dialogs

If the change was made on a domain Group Policy Object to force the change to take effect:

C:\> secedit /refreshpolicy machine_policy