Study Guide
Table Of Contents
- PayPal Certified Developer Program Study Guide
- Contents
 - List of Tables
 - Online Payment Processing
 - Internet Security and Fraud Prevention
- Why Every Business Should Be Concerned About Internet Fraud
 - Liability for Internet Fraud
 - Internet Fraud: What It Is and How It Happens
 - Who Is at Risk for Online Fraud
 - Reducing Exposure to Fraud
 - What Banks and Card Associations Are Doing to Prevent Online Credit Card Fraud
 - What PayPal Is Doing to Protect Your Business Against Fraud
 - Disclosure and Compliance
 - PayPal Fraud Protection Services
 - Review Questions
 
 - Getting Started With Account Setup
 - API Credentials
 - Name-Value Pair (NVP) API
 - Express Checkout
 - Direct Payment API
 - Transactions
 - Sandbox Testing
 - Answers to Review Questions
 - General Reference Information
 - Glossary
 - Index
 
 
PayPal Certified Developer Program Study Guide March 2008 121
Sandbox Testing
Testing PayPal Website Features
9
Instant Payment Notification (IPN)
You can use the Sandbox to test Instant Payment Notification, such as the PayPal Buy Now 
button or reversals.
Setting up IPN in the Sandbox
For information about implementing IPN, see the following:
z Technical overview at https://www.paypal.com/cgi-bin/webscr?cmd=p/xcl/rec/ipn-
techview-outside
z Order Management Integration Guide
test_ipn Variable. The Sandbox sets the test_ipn variable to a value of 1 in the HTTP 
response back to your IPN page. The purpose of this variable is to clearly differentiate 
between live and Sandbox IPN, so you can write your processing programs to work with either 
one. If the test_ipn variable is not in the HTTP response, you are working with Live 
PayPal.










