SQL Server can be licensed in a couple of ways, one of them being "per seat", at least that was the old naming for it. With that model the number of connections is determined by what are known as Client Access Licenses or CAL's. I believe the CAL's for SQL Server client access were part of the "Back Office" license that can be purchased for desktops along with any other licensing that is appropriate. If there are 300 Back Office CAL's then theoretically you should be able to have 300 "per seat" connections on SQL Server. Does that make sense?
Now, with all that being said, I haven't used that model since 2000 SO, it is best to read up on it here - http://www.microsoft.com/sql/howtobuy/licensing.mspx - as this is the final authority when it comes to licensing. 🙂
I will say that if you KNOW you are going to have a limited number of connections then most likely this is going to be your most cost effective model. Again though, review the information on the site. I believe there is actually some information to help you determine the right model for your business / customer.
David
@SQLTentmaker
“He is no fool who gives what he cannot keep to gain that which he cannot lose” - Jim Elliot