Transaction specification types

The communication between the three components involved in global transaction has been defined in specifications. The two protocols supported in the IBM Transformation Extender implementation of the global transaction management functionality are:

  • XA/TX protocol
  • OLE transactions specification protocol

There are differences in the way that each of these protocols is used in the transaction management models.

XA/TX protocol

The XA/TX protocol consists of two X/Open specifications: XA and TX.

The XA interface is a bi-directional interface between a transaction manager and a resource manager. Both managers must implement some functions from this interface. These managers use functions from the XA interface to communicate during the transaction preparation and commit activities.

The TX interface is used by the client application to contact the transaction manager. Only the transaction manager can implement this interface. This is used by the client application to notify the transaction manager that the transaction has been successfully committed, or not. If there was an error in the commit, the transaction manager takes over the data recovery portion.

Most of the commonly used resource managers support the XA interface and can be called XA/TX-compliant resource managers. However, there are only a few XA/TX-compliant transaction managers that are widely accepted or acknowledged.

OLE transactions specification protocol

The OLE Transactions specification protocol is a protocol developed to support the COM model and must be used on Windows platforms.