what is meant be “Anonymous Authentication” enabled and edit it to specific user

Question

iis 7.5 , for a site "Anonymous Authentication" can be 'enabled' and can be 'edited' it to a specific user.What does it mean. Enabling 'Anonymous' means allowing all the users, then what is meant for 'edit' it and add a specific user.

Answer 1

By default anonymous users use IUSR account when connecting to the site. You can change this user to a different user (who might have different privileges) and all anonymous users will use that account when connecting to the site, instead of the default IUSR account.

From MSDN on when to specify a different user for Anonymous Authentication

If your application is using other resources, such as COM+ components, databases, message queues, or UNC file shares, you will need to enable the appropriate permissions for the anonymous user.