Let the building begin

XML architect Brand L. Niemann of EPA says the discussion 'is moving back in the direction of actual implementation.'

Learning the necessary languages and technologies 'was an enormous challenge but also an enormous delight,' FEAPMO's Robert Haycock says.

Tom Fedor

Enterprise architecture effort moves from the abstract to apps'

Ready or not, Web services are coming to your agency.

Small interagency groups, directed by the Federal Enterprise Architecture Program Management Office, are working feverishly on reference models to define how agencies will link and reuse applications this year and beyond.

The 'how' will involve so-called Web services, a still maturing concept of dynamically coupling software applications over an IP network.

Experts in the public and private sectors say that the entire IT industry is moving toward a Web services model for on-the-fly delivery of content and services. They argue that agencies should get in on the ground floor by making their unique needs known to commercial developers of the services.

Currently, more than 135 specifications for Extensible Markup Language and Web services stand at varying stages of approval by standards bodies. Learning the details of those languages and technologies 'was an enormous challenge but also an enormous delight,' said Robert Haycock, FEAPMO's acting program manager. Now on detail to the Office of Management and Budget from the Interior Department, Haycock is one of the government's principal evangelists for enterprise architecture.

The CIO Council's Architecture and Infrastructure Committee is creating a subcommittee to recommend new technologies.

'The federal government really has no structure in place' for Web services, Haycock said. FEAPMO supporters believe that Web services can guide all three levels of the federal enterprise architecture business reference model unveiled last summer.

To succeed, however, agencies must get beyond the hype and varying definitions, Haycock said. That's why the year-old Web Services Interoperability Organization is emphasizing use of standards from the start.

'One of the problems that any adopter of new technology faces is the question: Did I bet on the wrong horse?' said Tom Glover, president and chairman of the interoperability consortium. Its members include the Defense Information Systems Agency, IT vendors and commercial organizations.

'Both XML and Web services are ready for prime time, but it depends what the prime-time application is,' said Brand L. Niemann, an Environmental Protection Agency computer scientist and chairman of the CIO Council's XML Web Services Working Group.

'On the one hand, they've tried to move the enterprise architecture discussion to a very high abstract level and get away from talking about specific software and systems,' Niemann said of the federal enterprise architecture proponents. 'On the other hand, it is moving back in that direction of actual implementation of the abstract models they're working on.'
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Glover and other Web services experts said the technology also is moving beyond the initial, much-hyped marketing battle between the two leading commercial development frameworks, Microsoft Corp. .Net and Sun Microsystems Inc.'s Java2 Enterprise Edition.

J2EE is ahead of the Microsoft approach, but both are close to maturity, said John Dodd, principal consultant for e-government solutions at Computer Sciences Corp. He said agencies will have to cope with mixed environments where client computers using Microsoft services must interact with servers running J2EE.

A key elements of the enterprise architecture effort, Haycock said, is the use of software components. A component is a reusable chunk of code. Software developers can combine components to build apps without writing code from scratch'a long-time goal that supports OMB's drive for agencies to share apps and the funds for them.

Enterprise architecture proponents want a library of interoperable components that can be reused anywhere within government.

XML, the core of Web services, is a markup language that tags content to separate it from its presentation. That separation, which is missing from the HTML that powered the rise of the Web, means multiple applications can use the same data.

There are at least six emerging standards:
  • Electronic Business XML (ebXML) is for e-commerce apps.

  • Voice Extensible Markup Language (VoiceXML) makes Internet content available to devices with voice interfaces.

  • Universal Description, Discovery and Integration (UDDI) helps organizations running Web services find one another and conduct transactions.

  • Simple Object Access Protocol lets Web services developed under one operating system run under another.

  • Web Services Description Language (WSDL) is a variant of XML for describing and finding Web services.

FEAPMO this year will release draft data, technical and service-component reference models, which will describe how to wed the architectural standards with the components.

The data reference model will contain metadata and an XML schema for shared data across government. 'Our intent is to have a central repository for XML schemas and metadata,' Haycock said at last month's XML 2002 conference in Baltimore.

The technical reference model will focus on standards and technologies'down to specific products in some cases'that facilitate component reuse, Haycock said.

The service component reference model will identify components for building apps.

Two paths

Another industry group, the Business Process Management Initiative, is developing the Business Process Modeling Language specification, said Jay Popkin, chief executive officer of Popkin Software Inc. of New York. BPML covers many of the same functions as WSDL, and the two may eventually converge, he said.

Standards bodies like to see two or more successful implementations of a technology before making a final decision, Niemann said.

For example, EPA has used the VoiceXML variant to create an emergency-response app. EPA regulates 1.2 million facilities around the country, from power plants to chemical factories. To make a database of the facilities accessible to the new Homeland Security Department, EPA structured a commercial telephone book app as a Web service.

In an emergency, EPA or HSD could use the Web service to alert people living around the facilities. EPA built a demonstration project serving only one state's facilities.

The big question, Niemann said, is whether such applications could scale up to serve the entire nation.

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