The current hype surrounding Web services is beginning to rival the hoopla that accompanied B2B exchanges several years ago. While it will take some time for Web services to be adopted on a wide-scale basis, it is clear that Internet-enabled standards (UDDI, WSDL, SOAP, etc.) and an intelligent, loosely coupled messaging infrastructure are the underlying building blocks that will make Web services viable as an enterprise application architecture. These techniques will enable internal integration--the first frontier of Web services--and prepare a business for future developments as they evolve.

Messaging Evolves

Web services--and the idea of assembling applications from discrete services--is changing the way the industry looks at messaging. Traditional message-oriented middleware (MOM) vendors rely on point-to-point connections between centralized, monolithic applications--an approach to software integration that was designed to live behind the safety of a firewall. Any connection beyond the LAN has been a high-cost and high-maintenance tentacle achieved through hard-coded connections using expensive, dedicated communication lines.

As Web services makes global interoperability technically viable, alternative architectures can bring increased ROI. Changes in the industry that are driving this shift include:

• Global interoperability through new industry standards. New Internet-friendly industry standards such as Simple Object Access Protocol (SOAP) and Web Services Description Language (WSDL) enable communication between systems that were once incompatible, such as CORBA and COM. This allows for interoperability among organizations that didn't originally plan to cooperate, and it doesn't require a heavy initial investment.

• Applications that reach across the extended enterprise. As standards make it possible to cross IT boundaries and competitive pressures necessitate it, e-business applications require organizations to integrate diverse software applications in remote locations. This is an expensive and time-consuming proposition for traditional infrastructures.

• IT's need to integrate with systems not under local control. The increased breadth of applications includes connecting to systems that are not managed locally and are therefore unpredictable. When services are upgraded or go offline, they can bring down other services and any associated business process if they are tightly coupled via RPC (remote procedure call) connections. Thus, dynamic yet asynchronous connections are required.