There was a time when EAI was the anti-thesis of SOA, but Enterprise Application Integration (EAI) is making a bit of a comeback within the SOA firmament. The fact is that it never really went away.
Back in the day people discovered EAI handled pesky real-world problems. You had a (fill-in-the-blank) workstation or what have you in the corner and you needed to connect it to (fill-in-the-blank) process or what have you in the back room … and quickly. A programmer would write to the two APIs and then labor the rest of his or her career maintaining the point-to-point solution.
The funny thing is that SOA has made a lot of progress in generally integrating all kinds of diverse systems, most notably mainframes. But, in some instances, Web services wrapping of mainframes may be reaching an illogical conclusion. Here and there, the back-end systems are becoming performance bottlenecks within the overall Web application scenario. The mainframe black box is ticking, and without genuine application modernization, trouble lies ahead. Point-to-Point integration may sneak back here, at least as a stopgap measure, until migration – don’t hold your breath – can be completed.
At the proper point in time, SOA came in with a higher level of abstraction, and it changed the equation. But there remained and will remain cases where EAI is the more economical alternative. The naming is the ironic part. Let’s face it: Some point-to-point connections have been renamed as “any-to-any” connections because the latter just has a better ring.
While discussing ”any-to-any” we might also look at one of the other dominant patterns of the EAI era – hub- and-spoke integration. In 2010, it was clear that a renewed drive toward SOA-savvy Master Data Management (MDM) was underway. On the face of it, MDM patterns don’t look that very different from the hub-and-spoke architectures of the past.
The key point with ”old school” MDM or EAI, as with new school social media or data analytics, is that design decisions are informed by a SOA perspective. It is a journey, but it is not a journey that needs to be taken without a road map.