This transaction processing is coordinated by Resource Recovery Services (RRS) on z/OS and WebSphere Application Server for z/OS. The IMS TM resource adapter is RRS-compliant and is designed specifically to work with RRS so that the Java transaction manager in WebSphere and IMS, as the resource manager, can work together to make consistent changes to multiple protected resources. The XA protocol is not used by the IMS TM resource adapter when running global transaction with Local Option.
To run a global transaction with Local Option, WebSphere Application Server for z/OS, IMS Connect, and IMS must run in the same z/OS image. Otherwise, use TCP/IP for global transaction.