It depends how you server security is configured and what type of CALs you own. Do you have any secured documents? What are you using for Autorization NTFS or DMS?
The company I work for has set up an additional server in a DMZ to handle users outside the network. The security is set-up with DMS authentication and Allow Anonymous. The filewall is configured to allow access in on ports 80 and 4747 to specific domains.
Are all your documents unsecured? If so, you can set Authentication to 'Never' on the QlikView Web Servers Authentication tab. Then all users could see the available applications.
On the QlikView servers set the Authentication to 'Allow Anonymous' on the security tab. Then for each document you you need to allow anonymous.
Which Server version and fix pack are you at?