My company is in the process of selling an application written in .Net with SQL 2005. Support will be provided in periodic licensing mode - support fee for x number of months. If the customer pays the support fee, the application will be available for x months of usage. If the fee is not paid, the application should lock up until a authoization code is entered. Grace period will be provided for continued usage.
The database will reside at the customer site - access to logins/users will not be available to us. The customer may not have access to internet - validating of the account through a website may not work. One possible option would be to send an encrypted authentication key that would be entered in the application login and would extend the license for a certain period.
Has anyone had any experience with a similar problem ? How would you go about it ?
Thank you in advance.