Transactions can be local or global. |
A local transaction is managed by the resource manager while a global transaction is managed by a global transaction manager. |
A global transaction in general interacts with more than one resource managers. |
EJB spec only defines a flat transaction (not nested). |
EJB requires that the EJB container supports the javax.transaction.UserTransaction interface defined in the Java Transaction API (JTA) for distributed transaction processing. |