This chapter covered the following issues:
A number of drivers contribute to the need for a broad-scale, general-purpose integration infrastructure.
The accidental architecture is the dominant design in use today. In this kind of system, the enterprise is currently not very connected at all.
Only 10% of applications are linked.
Of these, only 15% use any kind of middleware.
To date, distributed computing technologies have perpetuated, not solved, the accidental architecture problem.
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 draws value from lessons learned in EAI broker technology.
Integration is a departmental and corporate culture issue as much as it is a technical issue.
The ESB allows incremental adoption to occur in accordance with the individual needs of departmental development schedules.