CORBA Redux

Roger Sessions is a bit of a character. Witness his back-and-forth with Terry Coatta in ACM Queue around CORBA and Web Services. Sessions continues to point out that CORBA worked when CORBA was on both ends of the wire. Well, what else would you expect? Does HTTP work when HTTP is not on both ends? For some reason Sessions seems to believe that WS-* does not require WS-* on both ends.

For years now Sessions has promoted DCOM and now he promotes WS-*. A continuing theme of these promotions is that CORBA has failed. Certainly DCOM failed worse than CORBA. Moreover, as Coatta points out...

It looks to me like CORBA is more of a success than Web services.

The CORBA community learned many lessons and would have been even more of a success had that organization incorporated the web sooner and more naturally. WS-* usurped CORBA on the premise that the result would be simpler and better, yet years later both claims remain suspect.

Later in the exchange Sessions says something incredible. Upon admitting the WS-* specs are *more* complex than CORBA's, Sessions suggests that is OK...

I agree that the Web services standards are harder to understand than most of the CORBA specifications, but there’s one fundamental difference between these specifications and the CORBA ones. The CORBA specifications had to be understood by developers. The Web services standards don’t. Nobody needs to understand the Web services standards except for Microsoft and IBM because these standards are about how Microsoft and IBM are going to talk together, not about how the developer is going to do anything... These standards have no relevance to Joe or Jane Developer, none whatsoever.

This is ironic since a few minutes previously Sessions complained that these vendors are in danger of making WS-* too transparent...

In some sense, the transparent ability to make something a Web service is not really a good thing, because making an effective Web service requires a much more in-depth understanding of what it means to be a Web service.

Coatta catches this apparent contradiction...

It sounds like what you’re saying is that the tools that automatically supply Web services interfaces are, in fact, absolutely necessary because they’re that insulation between the developers and the underlying protocols. At the same time, they’re the downfall that’s making it possible to generate poorly architected systems. Two-edged sword?

Sessions has little to defend himself with other than to suggest that although these tools don't prevent bad architectures, just think how bad the architectures would be without those tools.

I'd give Coatta the victory in this debate. Too much confusion from Sessions who has not made up his mind whether tools, protocols, or APIs are good or bad...

The big difference between Web services and CORBA is that the Web services people said right from the beginning: there is no API.

So there is no API, because those are bad. But the protocols are damn near impossible to understand. But that is good, because we only need two vendors and they can provide tools. Well, as long as they don't provide APIs, 'cause that would be bad.

The only thing more confusing than the mess of WS-* specs is the explanation Sessions is trying to proffer.