SET Secure Electronic Transaction™

SET™ Specification

SET Secure Electronic Transaction™ SET Secure Electronic Transaction™ defines a mechanism to secure payments over open networks such as the Internet. The specification was originally developed by MasterCard and Visa in cooperation with a number of technology companies. The specification was assigned to SET Secure Electronic Transaction LLC.

SETCo logo Thanks to the Wayback Machine, you can view the SETCo website as it existed on October 11, 2002:

The last official version of the specification was version 1.0. That version of the specification was clarified by a number of technical bulletins issued by the SETCo Dispute Resolution Board. In addition, compliance tests provided a great deal of information about the expected behavior of compliant applications. Finally, there was a list of known problems (although the list is not comprehensive).

Because of a great deal of ambiguity and a number of errors in version 1.0 of the specification, SETCo started (but never completed) an effort to substantially update the specification by producing version 1.0.1 of Book 2. The new version did not change the base protocol, but it would have provided more clarity about how to implement the protocol.

SET™, SET Secure Electronic Transaction™, and the SET Logo are trademarks of SET Secure Electronic Transaction LLC.

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