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More legacy gain than pain with SOA

by Keith Rodgers
June 9th, 2003

Using web services for legacy integration means confronting an inevitable culture clash between different generations of IT. But some organizations still believe it's worth it.

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Despite doubts about the security and reliability of linking to legacy systems with web services, standardization promises to ease integration pains:
  • Use of web services for legacy integration is growing
  • But mainframe specialists worry about security and performance integrity
  • There's a cultural divide between the different generations of IT
  • Integration software vendors can help broker relations
  • For users like Miami-Dade county, the expected benefits justify committing to web services

Glossary terms: legacy, SOA, integration, Java, web services, lookup tool

Integrating mainframe and other legacy systems with the rest of the IT infrastructure has always been a big task. Many organizations are now starting to look to web services as a potential way to open up these key company assets.

Vendors claim their customers are using web services to help solve specific problems where integration has proved difficult in the past. They report that most companies are taking it step-by-step, keeping their web services activity inside the firewall because of the lack of established web services security standards. But a handful of early adopters, such as Miami-Dade County in Florida, have set out on vast integration programs that span the entire back-end legacy setup.

Given the huge amount of time and resource that's been put into maintaining legacy systems over years and even decades, it's hardly surprising that even limited projects are causing concerns in the mainframe environment. Regardless of the integration method, opening up access to a legacy system always involves some kind of trade-off.

More flexibility may be good for the overall IT environment, but each legacy access point is a security worry and may impact the performance of the host system. In the open-access, on-demand environment of a service oriented architecture (SOA), newly-connected applications risk eating up mainframe resources with unpredictable query requests.

These issues are exacerbated by the very different natures of the mainframe and web services environments. "One of the things about legacy systems is that they're so arcane to most people," says Jake Freivald, marketing director at legacy integration specialist iWay Software. Procedures for accessing databases, for example, vary significantly in the two environments. "Most people who develop web applications don't know what a hierarchical database looks like," he says, referring to the non-relational database architecture favored on the mainframe.

Different perspectives
The problems go beyond the technology — as Freivald says, "culture clash has as much to do with it". Someone who's spent 20 years doing development work for the IMS mainframe platform has a whole different perspective from a recent college graduate who's spent three years developing in Java. "It's not that they don't want to open up the mainframe — they know the mainframe needs to remain relevant, and it should do. But people on the mainframe are concerned about stability, integration of the environment [and] reliability. Someone in the desktop environment is used to things that break quickly and is not used to so much security."

What that means in practice is that legacy integration software and services providers — such as iWay, DataDirect and ClientSoft — effectively become brokers between the two worlds. Provided web services don't impact the mainframe architecture — leaving the legacy IT experts in control of access and security — the mainframe people are comfortable. Likewise, the front-end developers want to ensure they don't have to compromise the .NET or Java environment they know. Integration specialists layer web services on top of the mainframe to eliminate some of the complexity, ensuring front-end developers and users don't have to understand the underlying data structure.

Miami-based ClientSoft, for example, specializes in web services that reside on the mainframe, behind the protection of the legacy system's security. Unlike traditional "screen-scrape" solutions, which simulate a terminal but have to be updated whenever the underlying application changes, its ServiceBuilder application runs native in environments like CICS and takes direct advantage of the mainframe's signature speed and reliability. ServiceBuilder is also bi-directional, allowing legacy applications to not only publish but also consume web services.

SOA integration
While most ClientSoft users are content to deploy the technology for specific integrations, Miami-Dade County is aiming higher. It is embarking on an ambitious project to build a service oriented architecture, demonstrating that web services integration is viable in a multiple mainframe environment.

Serving more than a million inhabitants of the non-metropolitan areas surrounding Miami, the county first used the Web to open up its back-end mainframes in the late 1990s. It gave the public direct access to specific host systems through a web-based self-service interface, as well as giving building inspectors wireless access from the field. Since then, it has also saved hundreds of thousands of dollars allowing customers to apply for local government permits online.

Systems support manager Carma Suarez says that building an SOA will allow the county to both improve customer service levels and cut costs. The move will standardize systems integration both at a local level and with state and Federal authorities, and will reduce overall development costs by allowing the county to reuse services in many different processes, "instead of reinventing the wheel every single time."

Planned developments include a project to standardize access to the county's Property Tax Appraisal System, which is used by every one of its 40 or so departments, so ensuring that individual departments don't need to maintain a variety of different interfaces. The largest initiative is the county's Answer Center Project, which is designed to let members of the public call, fax, email or enter queries over the web for any issue affecting the county, using a single access point. Internally, that setup requires extensive integration with a vast range of legacy systems. According to Suarez, the county has agreed that every single integration point will be a web service — and indeed, that every future integration will be carried out in the same way.

These kinds of initiatives will be closely watched in both the public and private sectors as demands for transparency and data dissemination increase. For once, technology could be the key to bridging the generational divide, since if security and performance integrity can be maintained, mainframe experts' reservations about web services may be overcome. But it will be the ability to at last deliver cost-effective legacy integration that will be the clincher. Such compelling business benefits, if achieved, will amply repay the effort invested in bringing these two contrasting cultures together.

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