Using XMLink Universal Gateway

Chapter 2. XMLink Universal Gateway Architecture

XMLink Universal Gateway provides Oracle Tuxedo applications access to services deployed on other Enterprise Information Systems (EISs).

Figure 2-1 XMLink Universal Gateway Components

The Tuxedo Client

With XMLink Universal Gateway, the Tuxedo client makes service calls in the usual manner using tpcall to call services. XMLink Universal Gateway does not require anything to be installed on Tuxedo clients.

After you enhance your Tuxedo applications to call new enterprise services, you only need to configure the XMLink Universal Gateway Tuxedo server to advertise those services for your Tuxedo clients.

XMLink Universal Gateway

XMLink Universal Gateway has the following components on the Tuxedo server machine:

XMLink Universal Gateway Tuxedo server—Advertises the availability of new services deployed in enterprise applications.

The XMLink Universal Gateway Tuxedo server shares with other Tuxedo servers its ability to advertise services to Tuxedo clients, but instead of executing the business logic itself, the Gateway Tuxedo server interacts with the EIS to execute its service calls. Using its GATEWAY_SERVICE, it advertises the availability of enterprise services and funnels those requests to the appropriate system.
Data translation layer—Supports customization of the XML data between the Tuxedo server and the EIS.
Delivery agent—Uses the selected protocol to send the information to the EIS. XMLink Universal Gateway can be configured to use the following delivery agents:
- RMI/IIOP
- SOAP-RPC
- EJB

The Enterprise Information System

The Enterprise Information System (EIS) contains:

Deployed enterprise services
Listener for the selected protocol (SOAP-RPC, RMI/IIOP)
(for RMI/IIOP) XMLink Universal Gateway Adapter EJB

The EIS is generally a J2EE application server, such as IBM WebSphere.

Accessing Enterprise Services

Irrespective of the delivery agent used, you will need to build and deploy services in your enterprise applications. These services can be Java classes, EJBs, COM components, Web services, or other implementations of business logic.

Using SOAP-RPC

For the SOAP-RPC delivery agent, you need an HTTP server that is configured to process SOAP requests.

Using RMI/IIOP

For the RMI/IIOP delivery agent, typically the J2EE application server is configured to process RMI/IIOP requests. You also need to install the XMLink Universal Gateway Adapter EJB which processes the RMI/IIOP requests, forwarding them to the SOAP layer.

Using EJB

For the EJB delivery agent, XMLink Universal Gateway can interact directly with the EJBs containing the business logic, without using SOAP, Web services, or the Gateway Adapter EJB.

Alternatively, the Gateway Adapter EJB can also be used in the configuration.