2012
Table Of Contents
- Instant Payment Notification Guide
- Contents
- Preface
- Introducing IPN
- Implementing an IPN Listener
- Identifying Your IPN Listener to PayPal
- IPN Testing
- IPN Operations on PayPal
- Using Fraud Management Filters With IPN
- IPN Variable Reference
- IPN Transaction Types
- Transaction and Notification-Related Variables
- Buyer Information Variables
- Payment Information Variables
- Auction Variables
- Mass Pay Variables
- Recurring Payments Variables
- Subscription Variables
- Dispute Resolution Variables
- Pay Message Variables
- Preapproval Message Variables
- Adaptive Accounts IPN Messages
- Payment Review Using Notifications
- Revision History
IPN Guide July 10, 2012 17
Introducing IPN
Non-IPN Notification Mechanisms
PayPal will then send one single-word message, VERIFIED, if the message is valid; otherwise,
it will send another single-word message, INVALID.
IMPORTANT: After you receive the VERIFIED message, there are several important checks
you must perform before you can assume that the message is legitimate and
not already processed:
Non-IPN Notification Mechanisms
You can use IPN with other notification mechanisms. For example, you can use PDT or the
API to determine real-time information about a transaction and let IPN notify you of any
changes after the transaction occurs.
If you are using PayPal Payments Standard, you can use PDT to obtain information about the
transaction. If you are using Express Checkout or Direct Payment, the PayPal API notifies you
of the status and details of the transaction immediately and automatically. In either case, you
can immediately display to your customer the information being returned from PayPal. You
should not use IPN for this purpose.