As the world prepares for the official debut of the Windows 2000 product line, AS/400 client/server professionals wait for another significant Microsoft beta to appear. Microsoft will soon release the first beta version of the Microsoft Enterprise InterOp Server, code- named Babylon. Based on the Microsoft Windows Distributed interNet Applications (Windows DNA) architecture, Babylon is Microsoft’s first significant foray into legacy integration (including the AS/400) since the introduction of Microsoft OLE DB Provider for AS/400 and VSAM component that comes with Microsoft’s SNA Server 4.0 package.

With Microsoft poised to release several new additions to your AS/400 network, I thought it would be valuable to discuss the Windows DNA architecture and what it means to the AS/400 client/server world. In this article, I examine the strategy behind Windows DNA, the different components that make up the architecture, and how you can exploit those technologies in your AS/400 shop, including the new Babylon and BizTalk servers. By looking at the network architectural underpinnings of Microsoft’s offerings, I hope to provide a working view of where Microsoft is taking its network products and how you can plug your AS/400 into its architectural viewpoint.

The Big Picture

There is a big picture here, one that involves many current and new technologies you may be familiar with: Component Object Model (COM), Extensible Markup Language (XML), IBM’s MQSeries software, Microsoft Message Queuing (MSMQ) middleware, OLE, and ODBC. These technologies form a larger puzzle that Microsoft calls the Digital Nervous System (www.microsoft.com/industry/ dns). Detailed in Bill Gates’ book Business @ the Speed of Thought, the Digital Nervous System is Microsoft jargon for how an organization uses information technology to create a digital infrastructure that enables e-commerce, knowledge management, and business operations solutions for competitive advantage. To facilitate the creation of a corporate Digital Nervous System, Microsoft is promoting a Windows-based architecture for distributed Internet applications. This architecture is designed to do a number of contradictory things.

First, the applications architecture must take advantage of new Internet technologies while incorporating the existing IT infrastructure (i.e., legacy applications on MVS,

AS/400, or UNIX systems). It must use modern (read as Windows) scalable computing solutions that embrace the Internet, client/server technology, and PC computing models while making it dynamic and flexible enough to change as business needs evolve. Finally, the architecture must lower the Total Cost of Ownership (TCO) of an enterprise system while making complex computer applications work. And by the way, this architecture must also be able to run on any network. Windows DNA was created to answers these needs.

First introduced in fall of 1997, Windows DNA attempts to take several existing and new pieces of Microsoft technology and incorporate them into a framework for applications that create the Digital Nervous System. In networking terms, Windows DNA is a three-tier application model comprising the following components:

• Presentation or user services
• Business services (business logic)
• Data services To satisfy the distributed and message-oriented nature of Windows DNA, these three tiers are known as logical separations within an application. To support each tier, Windows DNA can physically deploy an application component among any number of computers, so you may hear people speak of it as an n-tier architecture rather than as a three-tier architecture. (For an excellent overview of the n-tier model and Windows DNA, go to the MSDN Online Library at msdn.microsoft.com/library/default.htm and expand the Platform SDK/ Design Strategies and Standards/BackOffice Developer’s Guide/BackOffice Server and Windows DNA branches to display the Web page shown in Figure 1.)

When put together, the Digital Nervous System resembles Figure 2. It’s significant that each tier of the Windows DNA model is called a component because Windows DNA is built on Microsoft’s COM standard. COM and its more advanced sibling standard, Distributed Component Object Model (DCOM), are Microsoft’s standards for creating components (i.e., reusable binary pieces of software that provide services). In addition, Microsoft is developing COM+ for its Windows 2000 product line. COM+ is also part of Windows DNA and provides additional resource management, scalability, and data integrity functions.

Windows DNA architecture is based on distributed components that send and respond to messages. This means that you can easily access or control objects on remote computers by using messages sent through standard communications protocols.

XML’s Future Role

XML is also becoming a key component of Windows DNA applications. As you may know, XML is evolving into a universal strategy for defining and working with databases in Internet applications. As such, it provides mechanisms for structural definitions of your hierarchical data, validation procedures called Document Type Definitions (DTDs) for ensuring the integrity of your data, and data storage and transfer capabilities for moving data across the Internet in XML files, email messages, and other Internet applications. XML is a framework for creating distributed databases and is used in many of today’s Internet-based applications, such as online transaction processing (OTP) for electronic data interchange (EDI), Open Financial Exchange (OFX) for financial packages, and Channel Definition Format (CDF) in Web browsers. XML is working its way into several popular AS/400 application products, such as Lotus Domino (through its DataChannel RIO technology) and IBM’s Java Toolbox for the AS/400 (through its Program Call Markup Language, PCML, and Program Definition Markup Language, PDML, technology).

IBM has recently used XML-based tools to develop AS/400 Operations Navigator, which comes standard with Client Access Express for Windows (Express client).

XML is becoming ubiquitous in Internet development, and Microsoft is joining that movement. At the TechEd 99 developers’ conference in May, Microsoft expanded its commitment by stating that XML is so key to its success that it is incorporating XML as a native part of its products.

Windows DNA in One Paragraph

What do you know to this point? You know that Windows DNA is a framework for building distributed Internet applications for competitive advantage (i.e., a Digital Nervous System). Windows DNA applications use existing pieces of Microsoft’s component technology (including OLE DB, ODBC, MSMQ, and XML) as well as planned future pieces (the Babylon server and the BizTalk framework, which I discuss later) to build these applications. With this information, the picture is coming into focus, but how does the AS/400 fit into Microsoft’s scenario, and where do the two worlds meet?

Locating the AS/400 Strand of Windows DNA

I stated earlier that Microsoft uses a number of current and new technologies to create Windows DNA applications. The first thing to remember when discussing AS/400 integration with Windows DNA is that Microsoft wants developers who use existing Rapid Application Development (RAD) tools to develop Windows DNA applications. RAD tools include Microsoft Visual Basic, Microsoft Visual J++, INPRISE’s Delphi/400, Sybase’s PowerBuilder, and Sterling Software’s Cool:Plex (formerly known as Synon’s Obsidian). For Windows DNA applications, you can also use the following current AS/400-to- Windows integration techniques:

• OLE DB, ODBC, and ActiveX Data Objects (ADOs). You can use the OLE DB provider and toolkit that comes standard with Client Access. You can also use OLE DB with Microsoft’s OLE DB Provider for AS/400 and VSAM, which is included with Microsoft’s SNA Server product. In addition, a growing number of third-party vendors are also selling AS/400-compatible OLE DB providers, such as HiT Software’s OLEDB/400 product (www.hit.com). Although Microsoft is pushing OLE DB access over ODBC, you can also use ODBC data source names (DSNs) with ADO code. (For more information on OLE DB and ActiveX integration with the AS/400, see the Microsoft Universal Data Access Web page at www.microsoft.com/data/default.htm and the IBM Client Access OLE DB Support Web page at www.as400.ibm.com/ clientaccess/oledb.)

• Java Database Connectivity (JDBC) drivers inside Java applications
• Client Access components (including the OLE DB provider, ODBC drivers, ActiveX automation objects, and the Express client C/C++ APIs) used as services in Microsoft middle-tier technologies. You can enable these services in such middle-tier components as Microsoft’s Windows NT 4.0 Terminal Server Edition (TSE), Internet Information Server (IIS), and Transaction Server. (For more information on using Express client as a Windows service, see “Express Client Plays Monkey in the Middle,” MC, May
1999.)

• Other Microsoft servers such as the Microsoft SQL Server (for AS/400 database access) and the Microsoft SNA Server (for AS/400 host integration and connectivity)

• IBM’s MQSeries products. MQSeries (www. software.ibm.com/ts/mqseries) implements any-to-any messaging on more than 35 supported platforms, including OS/2, AIX, and AS/400 CISC and RISC machines. The Windows DNA architecture uses the MSMQ middleware server as its message queuing environment. Working in conjunction with a third-party product, such as Level 8’s FalconMQ (www.level8.com), MSMQ can exchange messages with MQSeries products and maintain messaging compatibility with client/server applications.

All of these existing AS/400-Windows integration strategies should serve you in good stead as you begin developing Windows DNA applications. As a matter of fact, many shops and vendors are already providing DNA applications that use these common AS/400 access techniques. So although Windows DNA is a relatively new concept, it builds on existing strategies to get the job done. This means that the new Babylon server should be an addition to your integration toolbox, not a replacement for existing techniques.

And What About Babylon?

In the past, Microsoft has treated interoperability as a side issue, something for its competitors and business partners to be concerned about. Because IBM positions the AS/400 as a server for non-IBM clients, IBM has traditionally worried more about AS/400- to-Windows connectivity. That concern has produced some interesting AS/400-based features, including AS/400 NetServer, Integrated Netfinity Server, the QNTC file system, the OLE DB provider, and many components in Express client. Until this point, Microsoft has pretty much relied on its SNA Server, SQL Server, and OLE DB Provider for AS/400 and VSAM products in addition to vendor solutions that provide AS/400 connectivity to its users. Although these techniques work, they have been somewhat lacking in AS/400 connectivity capabilities as compared to their IBM counterparts.

That may be changing, however. During his keynote address at the Spring COMDEX/ Windows World, Microsoft Chairman and CEO Bill Gates announced that “we’ve had to devote over a quarter of our R&D budget to interoperability, allowing you to reach out to any of your existing systems to create these very rich Web views.” (For the full speech, visit www.microsoft.com/billgates/speeches/04-19spcomdex.htm.) When Bill Gates tells the world that Microsoft is concerned about legacy system connectivity and devotes a significant portion of Microsoft’s research and development budget to interoperability, that’s news. Hopefully, Microsoft is serious about providing integration between its systems and everyone else’s. The first test of this new “commitment” is scheduled to roll into beta testing next month, when Microsoft is scheduled to release the beta version of the Microsoft Enterprise InterOp server, or Babylon. Babylon is Microsoft’s first new legacy connectivity offering since the introduction of the OLE DB Provider for AS/400 and VSAM, code-named Project Thor.

Although it’s difficult to discuss a product completely before the beta is released, here’s what I know about the package as of this writing. (Undoubtedly, this information will have changed before you read this, so check www.microsoft.com for more up-to-date information.) Babylon is a new application, data, and messaging server designed to interoperate with legacy servers, including AS/400, UNIX, and MVS servers. It is scheduled to ship with Microsoft BackOffice 5.0 some time in the second quarter of 2000. (Other reports say it will ship 90 days after Windows 2000, but these reports never specify which version of Windows 2000 it will follow.)

Babylon builds on the current Microsoft SNA Server, but you will also be able to run it over TCP/IP. Babylon may also include a software development kit (SDK) that contains common interfaces for the integration of legacy servers, including AS/400 data sets. Babylon will contain the usual AS/400 connectivity features, such as OLE DB for data access, and will be fully integrated with Windows 2000 tools for generating COM and DCOM application components.

Babylon will reportedly run on both Windows 2000 and Windows NT 4.0 servers. You should also watch for MSMQ middleware to be used for email and messaging between Babylon and IBM’s MQSeries middleware. (Remember, MQSeries runs on 35 different platforms, including the AS/400.) Babylon goes beyond Microsoft’s current technology by providing bidirectional interoperability with non-Windows applications. This means that an application running on an AS/400 could theoretically invoke a COM or COM+ component through Babylon on a Microsoft server.

Babylon is also said to provide connection to Microsoft’s new BizTalk Server, another beta product that will ship shortly after Windows 2000. The BizTalk Server is a message router and translator based on XML. Using the BizTalk Framework, a public set of XML schema that describe business documents such as purchase orders, the BizTalk Server uses XML for application integration and e-commerce. (For more information on the BizTalk Framework, go to www.biztalk.org.) Combined with BizTalk Framework use in other vendor products and connectors to the Babylon server (and its interoperability with

legacy systems), the BizTalk Server attempts to make XML the pipeline for carrying business data across the Internet.

Again, these are all planned releases and features that are subject to change as the betas come out. Consult Microsoft’s Web site for more information, but, with these new betas falling into place prior to the Windows 2000 server rollout, it looks as if Microsoft will be heating up the AS/400-Windows integration marketplace once again.

Windows DNA, ERP, and Financial Services

With the current focus on the enterprise resource planning (ERP) marketplace, it is also worth mentioning that a version of Windows DNA exists for manufacturing organizations: Microsoft’s Windows Distributed interNet Applications for Manufacturing (Windows DNA-M). Announced in February 1999, Windows DNA-M addresses many of the same issues as Windows DNA but focuses on the manufacturing marketplace and integration issues between the plant floor, ERP, and legacy systems such as the AS/400.

Several large vendors—including Marcam Solutions, J.D. Edwards, Siemens, Honeywell, Compaq, Rockwell Software, and Intellution—have already partnered with Microsoft on Windows DNA-M solutions. (You can find a complete list of partners on the Windows DNA-M Web site at www.microsoft.com/industry/man/developers/initiatives/initiatives.stm.)

There is even a Windows DNA initiative for the financial services marketplace (Windows DNAfs). On the Windows DNAfs Web page at www.microsoft.com/industry/finserv/initiatives/windowsdnafs, Microsoft lists more than 115 financial institutions and developers as supporters for this initiative.

Windows DNA for Fun and Profit

If you break Windows DNA into its various components, it’s easier to see how it can work in your shop. By understanding its basic architecture, you can integrate it more effectively with your AS/400 and the rest of your network and plan for the future.

Reference

“Express Client Plays Monkey in the Middle,” Jeff Van Heuklon and David Dilling, MC, May 1999

Related Materials

• “XML Today,” Don Denoncourt, MC, July 1999, available on the Web at www.midrangecomputing. com/mc/99/07/9907xml.pdf
• “XML: The Language of Confusion,” Don Denoncourt, MC, March 1999

DIGITAL NERVOUS SYSTEM

WINDOWS DNA

Figure 1: The MSDN Online Library is an excellent source of architectural information on Windows DNA.

• Built on COM
• Logical Separations
• Distributed and Message-oriented

• Framework

Figure 2: Windows DNA creates the architecture that makes the Digital Nervous System possible.

APPLICATION COMPONENTS

• User Services
• Business Services (Logic)
• Data Services