How on-line billing system works.

The majority of on-line billing companies (www.clickbank.com, www.ccnow.com, www.ccbill.com, www.ibill.com, etc.) works in the following way: Merchant subscribes with such company ( for free or for some fee) and receives an account on the server of this company. Then he specifies in this account the prices and URLs of the finish pages on which users will be directed after money transfer is made. Then he makes links to the on-line billing server from the Web page from which he would like to sell his goods. ( in our case this is the page for membership subscription). When user clicks on this link he will be directed to the on-line billing server which returns the form for the submitting credit card information. Then the server makes credit card verification and if everything is okay it directs user to the finish page that is specified in the merchant account. After some period on-line billing company sends to the merchant money check ( or makes money transfer on the bank account) on which all on-line payments during this period are collected.

Our script works with www.clickbank.com company but other companies can be used as well. The main useful feature of the www.clickbank.com is that after transaction the server returns receipt number of the transaction by GET method with URL of the finish page. Our cgi script that saves the receipt number for further user verification is placed on the finish. If on-line billing company you prefer does not send receipt number by GET method with URL of the finish page, our script has other options for effective (and secure) fee based membership subscriptions.
If you are admin and use method that differs from mentioned above for accepting membership payment, you can make money transfer in your way and then manually submit membership information (password, login, membership period, services allowed, etc.) via Web based interface to the membership database.