The services (in the Tuxedo's term) are special programs which implement business logic. The services could be in the context of a global XA transaction, in this case 2PC control will be set in motion. Each service which uses Virtuoso as resource manager has hdbc connection to the Virtuoso server. This connection is automatically opened when service activated. The connection string (OPENINFO) to the Virtuoso server is the connection string of the group of the service (see GROUPS section in the sample config file). The OPENINFO has the following format: "Virtuoso:user:password@NODENAME:port". The user,password and port are optional.