Licencing system

[seraphi]

Hello all,

I have an application that i have written and would like to impliment some form of licencing system so that i can track users, the application is free but i would like to impliment this now for support reasons.

Basically i'd like to know if any of you have had experience on how a licencing system works, i want to have the following type of system:

1. User downloads the application aftwer signing up and recieving his / her licence key.

2. User uploads application to server.

3. Application asks for the licence key before install.

4. A check is made (somehow?) to make sure the key is a valid one.

5. The key is available for the creators of the application to check that the site / key is legit.

So any ideas? :)

[Alan @ CIT]

Not particularly indepth, but you here goes:

1) Make a little download script that generates a unique licence key for each download and stores it in a database on your website along with the users details

2) When the user uploads and installs the application to their server, they are prompted to enter their licence key which is stored somewhere (file, database, etc).

3) When the user runs your product, it makes a "call home" to a script running on your server (see below). This call home only need be something simple such as using fsockopen to connect to www.example.com/check.php?licence=ABC123 (http://www.example.com/check.php?licence=ABC123) (where ABC123 is the licence key that you issued, and they entered on the install.

4) A script on your server called check.php sits there waiting for the application to "call home". When it is run by the "call home" script, it checks the licence key provided by your app ($_GET['licence'] in my example above) against your database of keys and customer details to make sure that it is valid. If it is, it just ignores it, if it isn't, it reports it to you (via e-mail, or such like) with the details of the website it came from, etc.

This is the general principle behind it :) If you have any more indepth questions, ask here, or drop me an e-mail (alan@citconsultants.co.uk)

Thanks,
Alan.