Re: How can we create two web server for internal and external users?
It's mostly a licensing flexiblity thing. With an Extranet server you loose the unlimited-number-of-documents feature but you gain flexibility in serving a large number of external users (e.g. partners, clients, etc.)
If you simply want to provide QlikView document access to employees that are mobile and already have access when connected through the internal network, I think a second QVWS (in the DMZ) is probably the better choice.