Windows Server CAL and VPN [duplicate]

Each device or user will need a CAL. It can be done eitehr way usually.

In a similar situation, for web hosting, you would use the web edition, which would allow you to connect an infinite number to the server, but that does not apply to VPN's and RDP, especially (unfortunately) since it does not include the file server role.

http://www.microsoft.com/windowsserver2008/en/us/r2-editions-overview.aspx

The way I would approach this is set up a Server 2008 R2 Standard or Enterprise edition, and use device CAL's. It is rare that I would choose device CAL's over uCAL'sCALs, but otherwise he would need one User CAL for every customer. With the device CAL's, he can estimate that he will have 10 users connected at any time, so buy 10 CAL's. The downside is that if user 11 tries to log in, he won't be able to, so estimate a little high.

Taking advice on windows licensing from someone other than a microsoft licensing specialist is only slightly more hazardous than jumping into a cage of underfed tigers wearing only a warm, raw steak sombrero. In general there are 2 types of licenses, Enterprise (which for servers have device CALs, and user CALS, and server CALS as components) and SPLA licenses. As soon as you say the word "customer" anywhere near the word "access", you have jumped into SPLA territory. I would strongly urge you to talk to a licensing specialist at microsoft who will happily tell you how to properly spend your money, and more importantly, take the blame when another licensing specialist tells you that your license is the wrong shade of mauve.

Here is what should be the definitive answer:

http://www.microsoft.com/windowsserver2008/en/us/client-licensing.aspx