User Guide

Introducing IPN
What is IPN?
8 June, 2009 IPN Guide
administrative processes that respond the messages. PayPal provides sample code that you can
modify to implement a listener that detects IPN messages.
The actions to take when your listener is notified of an event are specific to your needs.
Examples of the kinds of actions you might take when your listener receives an IPN message
include the following:
z Trigger order fulfillment or enable media downloads when a check clears or a payment is
made
z Update your list of customers
z Update accounting records
z Create specialized “to do” lists based on the kind of event
You are typically notified of events by email as well, but the IPN message service enables you
to automate your response to events. The following diagram shows how events can occur and
how PayPal responds with IPN messages that it sends to your listener:
The diagram shows requests and responses, which are the result of processing button clicks or
API operations on PayPal. PayPal sends an IPN message when it sends a response to a request.