IPN is stand for Instant Payment Notification . It is a message services that notify you of events related to Paypal Transactions .
IPN notify when an events occurs that affects a transaction , These events represents various kinds of payments ; however ,the events may also represents authentications ,frauds management ,filter actions and other actions such as refunds ,disputes and charge backs .
- IPN is messaging services that paypal uses to notify us about events ,these events includes :
- Instant Payments ,including express checkouts and direct credit card payments .
- eCheck payments and associated status ,such as pending ,completed or denied.
- Payments that may be pending for other responses ,such as those being reviewed for potential frauds .
- Events related to recurring payments & subscriptions .
- Authentications ,Which indicates a sale whose payments has not yet been collected by providers .
- Charge backs ,which are initiated by a credit card processors ; For example ,when a customer disputes a charge .
- Disputes ,Which are initiated by a buyer using the paypal resolutions process .
- Reversal , Which occur when you win a disputes or a charge back is canceled .
The IPN Protocol consists three steps :
- Paypal send your IPN listener a message that notify you for the events .
- Listener send the complete unaltered message back to paypal the message must contains the same fields in the same manner or pattern (order) and be encode in the same manner as the original messages .
- Paypal Sends a single word back ,which is either VERFIED or INVALID with what originally sent to them .
The IPN Process :
- The Button action from site initiates a payment that completes on paypal .
- Paypal sends your IPN a message that notifies you of the event.
. Your listener sends the complete unaltered message back.
4. Paypal send VERIFIED or INVALID