The ISP module of WFilter NG firewall provides a total solution of bandwidth rate limiting, cap limiting and reporting of ISP users. In this topic, I would like to introduce a paypal integration solution for your ISP service to run automatically. It works like this:
- Users get email/web portal notification of ISP account expire date.
- Users can click “renew” to make payment online via paypal.
- Upon receiving of a payment, payal will call a callback script to extend users’ expire date.
The whole process can all be done automatically. Below is a demonstration of certain steps:
The first, you need create payment buttons in your paypal business account.
The second, you need to have an order landing page in your website.
When users click “renew” in their userportal or email notification, they will be redirected to the landing page. The landing page shall parse the “token” field to get username, expire date and current bandwidth policy. So you can calculate the costs for renewing. You can find an example of the landing page in WFilter_paypal_sdk.
The third, you need to enable “Instand payment notifications” in your paypal profile for callback.
When enabled, paypal will call the callback url for WFilter NG firewall to extend user date. 
The full php SDK soure code can be downloaded at here: WFilterNGF_Paypal_SDK_1_0.zip
Please note, we only provide a simple callback example. To make it work, you need to do below modifications at least:
- Customize the landing page. For example, provide “1 month” and “2 months” choices.
- Customize the callback php script. The default script extend this user for one month only.
For any question, please feel free to contact IMFirewall Support. We’re always will to help.