Additional security for Remote Desktop

[Guest Baffledandconfused]

Hi,

 

In my office we have just started using remote desktop to log in to work

from home (Win 2003 server). We log in using our network user name and

password

 

However, employees may be logging in from insecure computers and we are

concerned at the risk of keylogging software. We want to have an additional

password, of which the user will be prompted to enter 3 randomly chosen

letters via drop down menus (like many banks do).

 

How do we do this? I know there are various token-based solutions, but we

really don't want to make people carry tokens.

 

Any help gratefully received.