So I am starting to build a shopping cart based site written in asp.net c#. I want users to be able to view and buy single / multiple products through their shopping cart, and checkout and pay for them via PayPal.
Now I have experience with PayPal and have built a similar site that used a IPN script to verify the user after a purchase, however this one is a little different.
This one is completly digital files. So once the user pays for a product/products I want them to be able to download it. This is where the problem is as I have no experience doing this. I have seen alot of packages available to buy where they automate this for you, but since I know how to allready write a IPN script im wondering how much harder this would be. All I would have to do is send them a email with a link to the file, once they have been verified via the IPN script correct? Does anyone know of any good tutorials about file download links? Im guessing there will have to be added security to stop them downloading it a million times etc...
The other thing is all these digital products are on an external server, and wondering if its possible to store them on that external server and have the user download it from there, or if I really should upload them to the server hosting the website?
Other than those questions is there any other security or other issues I should be thinking about? am I missing anything?
Any help is much appreciated. Cheers for your time.