Sam, in apparent response to my claims that some people see constraints as bad things, writes this;

There are those who appear to advocate a null architectural style with respect to data. Who claim that content type independence is not a bug but a feature. Who imply that few constraints on data is a good thing. Of course, there are no such people, this is only a strawman argument.

Very well. I was hoping to not have to name names, but here are some quotes from some very smart people who don’t understand what an architectural constraint is, or its value (or at least didn’t when they said what I’m quoting 8-), and who are implicitly suggesting that less constraints are better. And FWIW, I never said that anybody was advocating using the null style, only that it was the implicit result when you make arguments such as these.

• “Constraint implies limitation. The way Web services uses layering removes limitations”
• “The criteria should be at the architecture level, not at the implementation level. I would say that web services architecture allows for stateless web services”. Needs to be read in context.
• “As before, there is nothing in web service architecture that precludes caching”. Same message as the last one, but further demonstrates a misunderstanding of software architecture, as I explained in my response.

I’m moving on Wednesday, and sometime over the next day or two my DSL service will be cut off, which will take down my Web server, and with it, my weblog. I hope to be back up by the end of the week, but the odds of that going smoothly are pretty slim.

If you’re interested, I’ve kept a photo record of the renovation of our new house, plus some additional info.

I want to ask a question of the Web services community about software architecture.

My question is; Do you believe it is possible to make an error when architecting a software system, that would make it practically impossible for that system to be successful, no matter how much support there is for it in industry?

I ask, because if there’s one thing I’ve learned during my studies of software architecture, it’s that you don’t get something for nothing; you have to expend energy to reduce entropy, aka add constraints to induce useful properties. In several discussions I’ve had over the past three or so years, I’ve heard more than a few folks (most of whom should know better, IMO) imply that less constraints are a good thing.

If there are a significant number of “No” responses, then I’ll know to spend more time on software architecture education. If there are a significant number of “Yes” responses, I’ll focus on the specifics of the architecture of large scale systems (which is what I’ve been doing).

Thanks. I apologize that I don’t have comments set up to handle this. But hopefully doing it this way, responses will end up in more aggregators, and this important issue will get more exposure.

Ok, would somebody like to tell why the heck we need WS-Addressing? Just address the darned resources directly, and be done with it. There’s simply no excuse for hiding resources in the post-Web era.

Also note the telling mistake in the first sentence, which keeps being made despite my continually pointing it out;

Web Services Addressing (WS-Addressing) defines two constructs that convey information that is typically provided by transport protocols and messaging systems in an interoperable manner. (emphasis mine)

Repeat after me; protocol independance is a bug, not a feature.

I just thought I’d see what all the fuss is about, and check out Infopath. I just ran through the online demo that’s there.

Very nice, but like Edwin, I’ve really got to wonder about the wisdom of doing this as part of Office, as it’s just such a perfect fit for the browser. Hopefully the Office team is thinking this too.

The demo didn’t show much of the “Share” part, except for some out-of-place UDDI and WSDL stuff, which should just be chucked. This is such a perfectly RESTful system that there’s zero value in doing Web services. Hopefully what the demo didn’t show, was a means of publishing a form back to a Web server for activiation, constructing a workflow by linking forms together using hypermedia, yada yada… all that good Web stuff.

It’s also a perfect base from which to add RDF support, but I suppose we won’t see that until long after the Semantic Web is a huge success.

Congratulations to Werner Vogels and his group on having their proposal for (amoungst other things) emulating the Internet accepted for funding! Werner writes;

The philosophy behind the testbed is to use a small high performance cluster (4 nodes) with 20 Fast Ethernet interfaces and an internal Gigabit ethernet interconnect to emulate the core of the Internet (or what ever topology you want to emulate). These FE interfaces are connected to a number of switches that provide the connection to all the end nodes. We make extensive use of VLANs to emulate the AD connections, and last mile connectivity. The goal is to run eventually with a 1000 physical nodes, the current first phase proposal was for 252 nodes. Each node has 3 ethernet connections, and we use software to emulate 3 end-nodes at each physical node. The experiments run the real software that you would eventually deploy, no simulated stuff.

Which sounds very cool from a technical POV. But if you want to emulate the whole Internet, try selling off those nodes to independantly owned and operated profit centers that are competitive with each other. Now that’s emulation (or is it simulation?). 8-)

So says George Colony, the CEO of Forrester.

The Web is dead and will be replaced by an executable architecture

Bunk.