Anonymous access lets a user bind to the directory without providing authentication credentials. With access control, you can give anonymous users whatever privileges you choose. Often, anonymous users are allowed to read non-sensitive data from the directory, such as names, telephone numbers, and email addresses.
You can also restrict the privileges of anonymous access, or limit anonymous access to a subset of attributes that contain address book information. Anonymous access should not be allowed for sensitive data.
In cases where anonymous users have access to something, you may want to prevent users who fail to bind properly nevertheless being granted access as anonymous. See the require-bind-pwd-enabled in server(5dsconf) for more information.