A little over a week ago, Ron Schmelzer of ZapThink, who’s pretty well known as an expert SOA analyst, quietly snuck an interesting comment into the ESB brouhaha that developed here recently. The ESB proponents who expressed displeasure at my view of ESBs, especially those who quoted ZapThink in their defense, will want to read what Ron had to say. If you don’t feel like chasing that link, here’s what he said:
The poster (Curt) who says that ZapThink says that ESBs are an enabling technology on the road to SOA has mischaracterized our position. Speaking from ZapThink’s perspective, we don’t believe that ESBs are neither necessary nor sufficient to enable SOA. In fact, we’ve seen plenty of SOA solutions that leverage a wide variety of non-ESB infrastructure. To be as unambiguous as possible: ESB is vendor marketing spin. True, there is certainly capabilities within an ESB that *might* enable companies to produce truly loosely coupled, composite, and heterogeneous Services in an environment of continuous change, but you can just as easily build tightly-coupled, proprietary, point-to-point Service integration with ESBs. There’s nothing about an ESB that substitutes for the need to do architecture. And there’s nothing about architecture that requires the adherence to a particular technological infrastructure.
If you want to make SOA work in a heterogeneous environment, why would you want to limit yourself to one technology, one approach? You’re buying right into their strategy of locking you into a platform. That’s only good if you sell platforms. Wake up folks – architecture is YOUR responsibility, not that of some vendors hawking middleware!
So, don’t put ZapThink in the camp of the ESB bigots. We certainly are not. Implement SOA with intermediaries and REST. Why not?