3.5.4.10 Registering with Transaction Manager
If the higher-layer business logic wants to register with the transaction manager, the resource manager MUST perform the following actions:
The resource manager SHOULD set the Session Identifier field to a new GUID value as specified in [RFC4122]. Optionally, the resource manager MAY instead set the Session Identifier field to NULL GUID.
If the transaction manager's resource manager supports the CONNTYPE_TXUSER_RESOURCEMANAGERINTERNAL connection type as specified in section 2.2.1.1.3:
The resource manager MUST attempt to register with the transaction manager using CONNTYPE_TXUSER_RESOURCEMANAGERINTERNAL.
Otherwise:
The resource manager MUST attempt to register with the transaction manager using CONNTYPE_TXUSER_RESOURCEMANAGER.