Prevent simultaneous logins

Hi,

I would like to have (or build) a login script I could use to redirect members to a Web Based Training after succesfully login.
But can somebody tell me how I can prevent members sharing passwords/logins and avoid simultaneous logins.

I've been thinking about loging the IP-address in the DB and remove it after a sessionvariable has timed out. But I don't know this is the best way. In the WBT people need time to do the course without having to login time after time...
I also thought it should be possible using the global.asa...

I hope somebody can give me some help here to get started...

Thanks!

Arne.

Edited by Arne

Well if you are concerned with people sharing passwords I would create a table to associate IP addresses with username. if a user logs in with a certain amount of different ip addresses in a given time frame block the user. Maybe you should not take the whole IP as dial up users might be entering with different ip's over the day thus they all should be in the same class.