Using the term Web services tends to evoke the response of: what are they, and: how will they affect the way IT professionals do their jobs?
According to John Hagel and John Seely Brown in their article Your Next IT Strategy, (Harvard Business Review, October 2001), this "whole new approach to corporate information systems" may be going by many names: Microsoft with .Net, Oracle with network services, IBM's Web services and Sun's open network environment. Essentially, however, the assumption is that companies in the future will buy information technology as services provided over the Internet, rather than owning and maintaining all their own hardware and software.
"We believe that two of the great advantages of the Web services architecture are its openness and modularity. Companies won't need to take high-risk, big bang approaches to its implementation.
"They can focus initially on opportunities that will deliver immediate efficiency gains, incorporating new capabilities as the infrastructure becomes more robust and stable."
Until now information systems have been proprietary and companies have either bought or leased their own hardware. Hagel and Seely Brown said companies have "inevitably ended up with a mishmash of disparate systems" spread throughout different business units.
While ERP systems have solved some of these problems, most large enterprises still struggle with hundreds of incompatible systems.
This is the problem for which Web services is being advocated as the "cure all".
"The Web services architecture is completely different. Constructed on the Internet, it is an open rather than a proprietary architecture. Instead of building and maintaining unique internal systems, companies can rent the functionality they need - whether it's data storage, processing power or specific applications - from outside service providers."
Hagel and Seely Brown said the Web services architecture can be thought of as three layers of technology.
At the foundation are software standards and communication protocols, such as XML (Extensible Markup Language) and SOAP (simple object access protocol).
"These tools provide the common languages for Web services, enabling applications to connect freely to other applications and to read electronic messages from them. The standards dramatically simplify and streamline information management - you no longer have to write customised code whenever communication with a new application is needed."
The middle layer of the architecture, or the service grid as it is referred to, builds upon the protocols and standards.
"The service grid provides a set of shared utilities - from security to third-party auditing to billing and payment - that makes it possible to carry out mission-critical business functions and transactions over the Internet.
Hagel and Seely Brown warn that the role of the service grid cannot be "over emphasised".
"A robust service grid is vital to accelerating and broadening the potential impact of Web services. Without it, Web services will remain relatively marginal to the enterprise."
Finally, the top layer of the architecture is a diverse array of application services that automate particular business functions. It is this layer which is visible.
"Some application services will be proprietary to a particular company or group of companies, while others will be shared among all companies. In some cases, companies may develop their own application services and then choose to sell them on a subscription basis to other enterprises, creating new and potentially lucrative sources of revenue."
While the construction of the Web services architecture is still in its early stages, Greta James, research director, application integration for Gartner, said companies should not hold back, but deploy internally.
"Web services are still new. So there are concerns, such as transactional integrity, service level agreements, monitoring for billing, management and security ... [but] there are advantages of deploying internally for enterprises as it gives companies a chance to learn about writing Web services, which could bring new [revenue] opportunities by becoming a provider."
Hagel and Seely Brown said Web services should initially be viewed as an "adjunct" to current systems, and that early adopters are concentrating their initial efforts at the edges of their enterprises.
James said companies should deploy internally using SOAP and WSDL (Web services definition language); UDDI (universal description discovery, and integration) is not as important.
"It is also important to have a conceptual design, so applications are presented as services and invoke services, and also have the technology to invoke services."
James said companies need to develop in a way that encourages the design of applications as services. She also reiterated the importance of implementing with a tool that takes advantage of SOAP.
* Are Web Services just hype or the promise of the future? E-mails to firstname.lastname@example.org.