DOT/XM:An Enterprise-Wide Integration Solution


Development of an efficient three-tiered messaging architecture



IBM MQSeries for MVS/ESA

IBM MQSeries for AIX



Iona’s Orbix





IBM S/390

IBM RISC System/6000

IBM Compatible PCs

Tandem Non-Stop

Windows NT

ABN AMRO is headquartered in Amsterdam and is one of the top 20 largest banks in the world. The bank operates over 1,600 branches in 67 countries and has one of the most formidable banking networks in the world. ABN AMRO’s success is founded on strong local knowledge of major markets, as well as a breadth of services, including corporate finance, project finance, counter trade, import-export, transactions, foreign exchange and loan facilities.

The bank’s North American operation encompasses a 600-branch network spanning Canada, the United States and Mexico. ABN AMRO wished to establish reliable, high-capacity messaging connections between its existing back-office systems and the new client/server front-end. Aware that the challenge required an in-depth understanding of both integration challenges and messaging technology, Level 8 Systems, an IBM BESTeam and IONA Technologies’ OrbixWise partner, was asked to present a messaging middleware and distributed object solution. "From the outset of the project, we were looking to Level 8 to give us a knowledge transfer and help make it happen," said Alan Singer, Senior Vice President at ABN AMRO Bank in Chicago.

Level 8 engaged in extensive discussions with the bank in order to identify the first application which would benefit the most from increased scalability, flexibility and security. It became apparent that one of the project’s first goals should be to offer its customers seamless access to CashPro+, a cash management vehicle (e.g., wire transfers, stop payments, information reporting, etc.). The challenge in doing this would not be in developing an effective front-end, but in providing an architecture that would be flexible enough to support its legacy and changing back-end environments.

"Our strategy was to develop a three-tier architecture that involved no changes to client activities as legacy systems are added on at the back end," stated Singer. "Indeed, we could be changing from one legacy system to another or adding new applications. Our strategy involves not having to rewrite systems at the client end. Furthermore, we wanted total flexibility and the very important factor of scalability."

Level 8 Proposes a Total, Strategic Solution

Level 8 Systems proposed to ABN AMRO a strategic solution called Distributed Object Transactions (DOT/XM), a transactional framework and methodology that uses object and messaging component technology to integrate disparate systems to harness resources regardless of platform or network. Level 8 utilized both IBM MQSeries and IONA Technologies’ Orbix in the DOT/XM solution. MQSeries provided cross-platform messaging software, and IONA’s Orbix offered the implementation of the Object Management Group’s (OMG’s) Common Object Request Broker Architecture (CORBA). Specifically, the new three-tier solution would decouple the front-end systems from the back-end to create a common middle tier that would permit any client to reach any back-end service. In this manner, the introduction of new front-end services could occur with minimal or no revisions to the back-end and new back-end services could be added without modifications to the front-end clients.

This reusable, component-based approach created a framework whereby ABN AMRO could add additional applications (e.g., loan application processing, Web application, home banking, etc.) easily. In addition to implementing DOT/XM for CashPro+, Level 8 supported ABN AMRO in developing COMET (Common Enterprise Technology), an initiative to define and deploy a scaleable, common and reusable architecture throughout the enterprise. The goal of the COMET program was to ensure thorough integration permitting access from any customer from any geography through any media to any service.

This integration is accomplished, in part, by modeling the transaction flow of business objects using DOT/XM. Level 8 worked with ABN to identify a set of standard business rules needed for customer transactions, and then transferred each rule into shareable ‘business objects.’ These ‘business objects’ encapsulated heritage systems or CICS transactions in "wrappers," making the objects shareable across multiple platforms. These business objects are then contained in a Transaction Flow Engine as reusable objects, creating further enterprise efficiency and flexibility. DOT/XM may be used with the following transport protocols: MQSeries, MSMQ, TCP/IP and LU62.

ABN AMRO’s client systems uses dial-in modems with Win 3.1 PCs and customer service uses Windows NT running on a local, internal TCP/IP network. Servers are RISC System/6000s running AIX, and, for the back end, there are S/390 mainframe, Tandem, OS/2, or RISC System/6000 platforms. "We used business objects on a RISC System/6000 to link to our legacy systems," added Singer. "The business objects do ‘puts and gets’ of messages on the RISC System/6000. On the legacy systems we constructed a SHIM (Simple Heritage Interface Module) which takes the messages and translates them into requests, which are mostly CICS-based." DOT/XM formats messages into transactions the legacy systems understand and gets messages back from these systems. "Our need was for something, in which we were totally confident, that would reliably connect our server platform to all the different platforms running our legacy systems," added Singer.

The Positive Impact of an Integration-Oriented Approach

The DOT/XM implementation has positively impacted the bank’s operations by providing 500 of ABN’s corporate customers online access to various cash management services (e.g., wire transfers, stop payments and information reporting). By decoupling front-end applications from the back-end, the Level 8 and DOT/XM Team:

*Minimized dependencies: By decoupling, specific front-end applications were no longer dependent on specific back-end systems - affording the enterprise greater flexibility in changing back-end services and systems as needed.

*Simplified application development: By creating a middle tier containing a Transaction Flow Engine with reusable business objects, developers could focus on solving business problems — not just writing code for new applications.

*Reduced costs: Developers no longer needed to rewrite code when a back-end system was changed or modified — permitting them to focus on more important tasks, such as adding or combining business objects into new services for the front-end.

*Provided an open solution: DOT/XM enhanced ease of use and the enterprise’s current and future flexibility by utilizing industry (or de facto industry) standards, such as CORBA and MQSeries.

*Integrated new business acquisitions: DOT/XM’s middleware inserted business logic into the middle tier, isolating it from both the front-end and back-end systems. This approach placed the processing function in the middle tier; thereby, making it easier to add new business services to the front-end or back-end systems.

Now that the three-tier architecture is in place, ABN AMRO is now rolling out other systems for its varied business units and may even implement it worldwide. DOT/XM provides a flexible infrastructure on which the following services and media may be built: the Internet, mobile communications, multimedia applications, transaction-based systems and a whole new generation of network applications.


Steve Marini has nearly two decades of experience in systems design, integration, and management. He is a recognized expert in the design and implementation of advanced object technology and middleware solutions. He is currently responsible for Level 8 Systems’ (New York City) DOT/XM line of middleware products.

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