The International Standards Organization (ISO) has defined a standard that permits transaction managers from different vendors to interoperate. This standard is the Open Systems Interconnect-Transaction Processing Format and Protocol (OSI-TP FAP). The OSI-TP FAP defines the message formats and protocols for doing two-phase commit coordination between one transaction manager and another. Although some transaction managers support OSI-TP, all successful transaction managers rely upon their own proprietary two-phase commit protocols. As a result, the OSI-TP standard has relatively little support in the industry. MS DTC does not support OSI-TP.