Jon Udell posted some potential interesting discussion topics for the SOA Platform panel discussion at the InfoWorld SOA Executive Forum.
I am really looking forward to participating in this panel, not only because of the distinguished company I’ll be in, but also because for many businesses, investments in an SOA Platform based on Web services will solve significant IT problems and create strategic advantage. This is a great topic.
With respect to the question in Jon’s blog about standards and specifications, I am really not sure about the implication that the current Web services “stack” is designed for use in an SOA. (I put “stack” in quotes because the industry still does not have a single, consistent architecture for Web services. Microsoft and IBM are still promoting different versions, for example.)
Many of the specifications were developed before their application in an SOA was identified, and others were proposed more as features and functions needed for certain applications, whether part of an SOA or not. Many Web services applications need security, or reliabilty, even when they are solving a simple point to point interoperability problem.
I’d argue that most Web services technologies are generic, in other words, and not specific to their application in SOA infrastructure. It’s better to first define what’s needed for an SOA Platform based on the requirements of the SOA rather than working from what exists in current Web services specifications and assuming they provide what you need. This approach would also show us where the standards are insufficient for the purpose of an SOA platform, where features/functions are missing, etc.
Despite the fact that WSDL provides many of the things you need, it is not correct to assume that it is therefore equivalent to an SOA contract, for example.
Unusually this week I didn’t travel anywhere. Although to be fair I did drive in to the Hyatt at Logan Airport for the W3C Technical Plenary day. It might have felt more like going somewhere except that the trip was so familiar.
At the TP (this always confuses me since I spent more than 20 years in transaction processing, but then I remember that this is not the provenance of the W3C) the hot item was a panel discussion on the future of XML.
These events are sometimes more memorable for the people you meet outside the formal sessions. For example, just after lunch I caught up with my old friend Jim Melton, who was on the XML panel representing of the XML Query working group. It must have been 10 or 12 years…
The controversy over XML seems to boil down to whether or not the language is done. Standards committees have a tendency to look for additional work when their original charters expire, whether it’s really needed or not. This point was well made during the session.
Someone even got up during the Q&A to propose recinding XML 1.1, since it hasn’t caught on widely (see Noah’s talk for some details). The problem seems to be that XML 1.1 isn’t compatible enough with XML 1.0 – XML 1.0 parsers can’t handle XML 1.1 without significant modification.
Another interesting point of debate was binary XML. The main question seems to be whether binary XML should be a straightforward transformation of text XML, or whether a binary XML format should include structural information within it (and therefore be “parsable” in its own right). Everyone seemed to agree that a WG and a standard are necessary, since a dozen or more proprietary implementations already exist, but what that standard should look like remains hotly debated.
I was very glad to hear that our metadata proposal (as amended by Microsoft) passed in the WS-Addressing WG face to face earlier in the week. Everyone has talked about Web services supporting multiple transports from the beginning of SOAP, and in fact this is one of the main justifications for why WS-Addressing is necessary in the first place (i.e. Web services shouldn’t have to rely on any transport-specific addressing mechanism if they are to be truly transport neutral). But until this change was approved, the Addressing specification did not explicitly support the multi-protocol feature. My colleage Steve Vinoski has written extensively and well about this in his blog, and in fact led the effort.
With the metadata extension to WS-Addressing endpoint references in place, it will be possible to publish the same service over multiple transports, and provide failover and availability qualities for a service.
What I’m worried about now is getting the WS-Policy framework submitted to W3C. We need to progress policy in an open forum, the way WS-Addressing is being progressed, since metadata definition and management are so important. No one seemed to know for sure what the holdup is.
As a sad footnote to the week, I learned that my old friend Frank Willison passed away nearly four years ago. Ironically, I learned it in re-establishing contact with another old friend, Jeff Mandell. I spent the rest of the week filled with memories of those great days at Digital, from 1984 to 1990 or so when we were all just kind of starting out and Digital was doing great. We shared a lot of laughs, music, and (embarrassing as it is to admit) foreign cigarets in the hall… Like the tributes all say, Frank was a wonderful human being, and a great writer. We used to tell him to quit the day job and give Dave Barry a run for his money. Check out this excerpt from the Best of Frank:
“Partway through Elliotte Rusty Harold’s talk about namespaces, I realized where this relentless drive toward abstraction was taking us. Every new level of abstraction draws the computer-based world closer to the concepts we talk about in the real world. We’ve moved from waves to bits to data to information to infosets to application objects. As this process continues, some ambitious Comp Sci graduate student will realize that somebody already created the tree structure mapping the highest level of reality. That person was, of course, G. W. F. Hegel. Hegel’s dialectic led him to create a map of reality that, at the top of the tree structure, divided everything into either the material or the spiritual realm. That dichotomy was resolved in God, and, my friends, that’s about as far as you can go.
“That ambitious Comp Sci grad student, eager to get his Ph.D. and begin making real money, will create The Two Final Infosets: MatterML and SpiritML. Then, late one night, as rain falls in torrents and lightning flashes outside his laboratory windows, he’ll run XSLT to transform the material world to the spiritual world. We’ll be gone. The last material object on earth will be that graduate student’s open copy of XML in a Nutshell. It makes an editor in chief proud, in a perverse kind of way.”
It seems clear from this that the Semantic Web folks are barking up the wrong tree… 😉
I can’t believe I lost touch so completely that I didn’t even know he was gone.
The lesson is to keep up better with friends. And so was it great to see Jim again after all these years.
Yesterday I presented at Web Services Edge East on the topic of getting started with service orientation and an SOA.
It was standing room only, which says as much about the size of the room as the popularity of the topic 😉 But nonetheless it seemed like a good turnout, and I got a lot of questions and request afterward for a copy of the presentation. (Please send me an email if you’d like a copy, too.)
You can also find a link to the article I wrote for Web Logic Developer’s Journal on my Sys-Con author’s page. The presentation is pretty much based on the article.
And the material in both the article and the presentation was based on early drafts of the book I wrote with Greg Lomow, which my editor tells me is doing pretty well so far.
A lot of questions came up about how to get started designing services, about the capabilities of an ESB with respect to SOA infrastructure, and the relationship of business process management to services.
It really seems like there are a lot of definitions of SOA and ESB out there in the marketplace right now. But as I pointed out in the presentation, I think that the definitions will eventually have to settle down onto what’s established in the marketplace.
For example, Credit Suisse has an SOA in production with more than 700 services, processing about a billion transactions a year. Here’s David Chappell’s presentation on SOA that references Credit Suisse and a reference to the often cited Gartner study on the Credit Suisse SOA (sorry but unless you pay you only get the first paragraph).
Deutsche Post is another company building a large scale SOA. Their success to date is being watched carefully throughout the industry, and they are members (along with IONA and several others) of JSR 208, the Java Business Integration specification effort.
These real projects, meeting real business requirements every day, are the kinds of things that will make SOAs and ESBs real, and provide the foundations for the real definitions once the hype settles down.
“and now, ladies and gentlemen, just back from an extensive tour of the Far East, Africa, and the subcontinent…”
Well, just back from the Gartner conference in Florida, anyway, which sure feels like another world when there’s already snow on the ground here in the Boston area.
One of the highlights was Roy Schulte’s keynote the first morning (sorry, but the only link I could get is to the entire conference agenda), in which he identified the Enterprise Service Bus (ESB) as the next wave in middleware. Roy said that everyone will need one for use in future integration projects, and he provided a list of ESB vendors, IONA among them.
More than 160 people attended my talk on Tuesday, and we had another pretty good crowd for the SOA and Events panel on Wednesday.
I have to say that I do not consider events as something distinct from services, though, and look forward to the day when Gartner combines their SOA and event driven architecture (EDA) paradigms.
I was also personally very pleased to hear Gartner refer to WS-CAF as “one of the three advanced Web services specs to watch” at OASIS! Especially since we have just successfully advanced WS-Context to OASIS Committee Draft, and held an interop demo at XML 2004 with Oracle and Arjuna.