There is a key called WebSessionMinutes in the Customization Manager under Web Interface | System. This key dictates the number of minutes before a customer will be automatically logged out of the ILLiad web interface if they are not actively using the web pages. This will alleviate problems with customers leaving a public terminal while still being logged into ILLiad and someone else submitting fraudulent requests as that customer. Set this key to the number of minutes that you feel is best for your ILLiad system.