"ESB is really a design pattern," LeBlanc maintained, while simultaneously noting that IBM had indeed launched an ESB product.

"There are actually two patterns that we are starting to see evolve with customers," he continued. "One is a very basic pattern where customers are trying to connect web services, and that's all they're trying to connect. And therefore that's what the WebSphere ESB product is going to enable customers to do."

"Then we have got the advanced ESB, which is based on our WebSphere Message Broker, that takes all of these standards-based web services and enables them to all be connected, but enables you to connect to non-standard sets of interfaces, because that's what customers are faced with integrating."

"WebSphere Message Broker is not a lightweight, simple mechanism," added Steve Mills. "It's a more sophisticated mechanism that supports both asynchronous and synchronous transactions at extremely high data rates and is designed to give a broad range of interfaces as Robert points out, and different types of connections."

"There is also very sophisticated choreography, flow control and recovery services there," Mills noted, "so don't view it as some simple thin wire mechanism for connecting, it's actually much more sophisticated than any of the typical claimed brokers in the market today."

"The WebSphere ESB product," LeBlanc added, "is really there for customers who are looking to base this around a set of open standards, while the WebSphere Process Server takes you beyond that level and offers a lot more capability. The ESB is inside of the Process Server, and we believe that over time most customers will see the value of the Process Server and go to that higher function set of capabilities."

"This further solidifies the ESB product category as a force in the industry with significant staying power," commented Web Services Journal editorial board member and Enterprise Services Bus pioneer David A. Chappell, vice president and chief technology evangelist for Sonic Software, the company perhaps most closely associated with popularizing "Enterprise Service Bus" as a term.

Chappell took IBM to task for having indulged in mis-direction as it caught up in the race to create its own ESB.

"As the inventors and leading providers of ESB technology, Sonic has for several years taken a hard stance that ESB is a product category, and not just an abstract pattern. IBM started an industry debate of ''pattern vs product' a couple of years ago as a way of laying down a smokescreen while keeping customers locked into the Sargasso sea of technology under the WebSphere brand."

But all's well that ends well, Chappell conceded: "It is good to see that IBM has finally come around and recognized the shift in IT thinking that ESB is indeed a product category, much like the appserver category that developed in the late 90s. This further solidifies the ESB product category as a force in the industry with significant staying power."

Steve Mills was appointed Senior Vice President and Group Executive, IBM Software, in July 2000. In this capacity, he is responsible for shaping IBM's overall software strategy and directing IBM's $14 billion software business. Mills has played a leading role in the growth of IBM Software Group since its inception in 1995.

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