Because of different global transaction identifiers (GTRIDs) are used in different domains, the transaction crossing domain are loosely coupled even if the branches of the transaction are running on the same database. This feature enables transactions to be performed in remote domains using the same GTRID. The same GTRID allows branches on the remote domain to share locks, enabling tight coupling. The branches will be tightly coupled if they are running on the same database (if the database allows).

For more information about configuration, see Introduction to Using Oracle Tuxedo Advanced Performance Pack.