I have a PHP application that is to be packaged up with Apache, Mysql and PHP and installed on an internal Windows network. I wish to be able to create a time trial of the application so that it expires after a set period of time eg 30 days. I have ran through several scenarios without coming up with anything concrete as anything that I do to try to limit access for a period of time could be circumvented by anyone who has any knowledge of PHP as they will have access to all the source code.
My solution is to distribute a key with the application which is passed to a remote server on the first run after installation. The key, date and IP Address are saved in a database on the remote server. After this each time the application is accessed it connects to the remote server and compares the key, ip address and date. If the IP address and key match what is stored and the date difference is less than 30 days the application will function, otherwise it will not.
This is all I have come up with. Can anyone suggest another method for creating a 30 day trial on a locally installed web application?
ionCube can encrypt PHP files, and make them expire in a set time period using the
expire-inswitch:http://www.ioncube.com