Enterprise Services Bus ---2 The State of Integration

Author: Harold Wang

http://blog.csdn.net/hero7935

2.1 Business Drivers Motivating Integration

2.2 The Current State of Enterprise Integration

The accidental architecture is something that nobody sets out to create; instead, it's the result of years of accumulating one-of-a-kind pointed integration solutions. In an accidental architecture, corporate applications are perpetually locked into an inflexible integration infrastructure. They continue to be treated as "silos" of information because the integration infrastructure can't adapt to new business requirements

The integration broker at the center of the diagram represents an island of integration that connects some applications at a departmental level. However, this does not imply that it is being used to connect everything together. The integration broker is usually relegated to being just another piece of infrastructure in the mix, the result of a well-funded project that achieved moderate success, but then didn't continue to integrate everything as promised.

In summary, the accidental architecture represents a rigid, high-cost infrastructure that does not address your organization's changing needs, and suffers from the following disadvantages:

• Tightly coupled, brittle, and inflexible to changes

• Expensive to maintain due to multiple point-to-point solutions

• Changing one application can affect many others

• Routing logic is hardcoded into the applications

• No common security model; security is ad hoc

• No common API (usually)

• No common communications protocol

• No common ground on which to establish and build best practices

• Difficult to support asynchronous processing

• Unreliable

• No health monitoring and deployment management of applications and integration components

• Author: Harold Wang

  http://blog.csdn.net/hero7935

2.3 Leveraging Best Practices from EAI and SOA

---Adopting XML

---Adopting WS and SOA

2.4 Refactoring to an ESB

Getting from the accidental architecture to a uniform integration infrastructure on a global scale may seem like a daunting task. It's not realistic to get everything ready and then flip a switch to get all your applications onto the new infrastructure. This has been a major reason why organizations continue to add on to the accidental architecture as the status quo, even with the knowledge that they are only perpetuating its associated problems.

Author: Harold Wang

http://blog.csdn.net/hero7935

---Connecting into the Existing EAI Broker

The third phase of our ESB adoption project involves bridging into a department that has already been partially integrated with a hub-and-spoke EAI broker.As noted previously, adopting an ESB is not an all-or-nothing proposition.

 

2.5 Summary

Hub-and-spoke EAI brokers have had moderate success. However, they:

• --Are largely proprietary
  --Failed to provide organizations with a standardized integration platform that could be applied to general-purpose use across an enterprise

The ESB allows incremental adoption to occur in accordance with the individual needs of departmental development schedules

Author: Harold Wang

http://blog.csdn.net/hero7935