Active Directory Licensing [duplicate]

Possible Duplicate:
Can you help me with my software licensing question?

I can't seem to find a clear answer to this question.

What type of licenses do I need to buy ensure that everyone in my organization is licensed to use Active Directory. We want to use AD to authenticate users in our timekeeping system. Am I going to need server CALS? Is there a special AD license?

We have about 5000 users who'd need to authenticate to this system.


In addition to a license for each DC to run Windows Server, you will need CALS.

For win2003, there are device CALS and User CALS, which you choose depends on how your company is setup.

If you have shift-workers sharing the same machines, then you'll need at least as many Device CALS as you have computers authenticating against the DC.

If instead you have 5000 employees each with their own device authenticating, you will need 5000 user CALs.

I hope this helps.


I hate CALs.

My basic understanding of CALs:
1- A "device" CAL allows unlimited users on a single computer to contact all servers in the organization.
2- A "user" CAL allows a single user on any computer to connect to all servers in the organization.
3- You don't need a "device" CAL for the computer and a "user" CAL for the user. Either a user CAL or a device CAL is must be available when the connection is made to the server.
4- Windows Server CALs cover authentication through AD (i.e. logging in to the domain), accessing file shares, authenticated access to IIS, etc.
5- There are separate CALs for most other MS products, including Exchange and the non-bundled SharePoint.
6- I believe that an Exchange CAL is included with Office Pro. I suspect that a SharePoint CAL is as well, although I don't know that with certainty.
7- MS CALs are "named" rather than "concurrent". A device consumes a device CAL even when powered off, and a user consumes a user CAL even when logged off. However they can be transferred from one device/user to another as long as the first consumer is disabled or removed.

This is likely a vast over-simplification, and there are certainly loads of exceptions, caveats and gotchas. Any corrections/additions/etc. are welcomed through the comments!