You may have read earlier articles in which I discussed the service-oriented architecture generation gap: the divergence between SOA solutions that have evolved from earlier application integration products and those written from scratch to leverage evolving Web services standards. Those discussions concluded that Web services-based, lightweight, plug-and-play frameworks could eventually emerge that would challenge enterprise-grade Enterprise Service Bus (ESB) solutions. Customers would be able to "roll their own" ESBs using best-of-breed, standards-based point products. Recent announcements from Reactivity and Forum Systems bring this vision closer to reality.

Reactivity's solutions have traditionally been positioned as XML gateway and acceleration products, while Forum Systems has made its name by providing enterprise-grade SOA and Web services security. Although each vendor has distinct products, the technology behind both solution-sets is based on deep XML packet visibility and manipulation capabilities. This gives both vendors a bird's eye view of messaging traffic, positioning them for expansion into multiple additional product markets, including transaction management, monitoring and mapping. Reactivity's recent announcement of XML Enabled Networking (XEN) and Forum Systems' announcement of DynamiX, a Service Enablement Platform (SEP), indicates these vendors have taken advantage of their versatility to move forward with ESB-like functionality.

XML gateways add reliability to messaging systems with functions that include message mediation and policy-based content routing. XML is a text-based protocol while acceleration solutions optimize network performance by reducing repetition and bulk. The loosely coupled, distributed nature of SOA requires specialized security and Forum addresses these complex composite transactions with specialized functionality that has earned the very high level certifications required for U.S. government deployments.

ESB functions vary among vendors and include gateway, acceleration and security. All ESBs are tasked to facilitate reliable communications and in addition, may also provide multi-protocol support, message exchange, policy-based routing, orchestration, application adapters and service discovery. Both XEN and DynamiX take on some of these functions.

Denise Dubie is senior editor with Network World.