Mastercard and VISA have cooperatively developed the Secure Electronic Transactions. SET combines ideas from the previous proposals by MasterCard (SEPP, which is based on iKP) and VISA (STT), and was designed by GTE, IBM, MasterCard, Microsoft, Netscape, SAIC, Terisa Systems, Verisign, Visa.

The SET Secure Electronic Transaction TM protocol is an open industry standard developed for the secure transmission of payment information over the Internet and other electronic networks. SSL Secure Socket Layer (SSL) (developed by Netscape Communications Company) is a standard that encrypts data between a Web browser and a Web server. SSL does not specify what data is sent or encrypted. In an SSL session, all data sent is encrypted.

SET uses a system of locks and keys along with certified account IDs for both consumers and merchants. Then, through a unique process of "encrypting" or scrambling the information exchanged between the shopper and the online store, SET ensures a payment process that is convenient, private and most of all secure.

SET:
1.Establishes industry standards to keep your order and payment information confidential.
2.Increases integrity for all transmitted data through encryption.
3.Provides authentication that a cardholder is a legitimate user of a branded payment card account.
4.Provides authentication that a merchant can accept branded payment card transactions through its relationship with an acquiring financial institution.
5.Allows the use of the best security practices and system design techniques to protect all legitimate parties in an electronic commerce transaction .