William Vambenepe's blog

I just found out that I completly missed some interesting information about Oslo-related efforts at Microsoft. Back in February, Mary-Jo Foley reported on a new modeling language (code-name “D”, apparently) that is part of this initiative. And more recently she reported that David Chappell gave a presentation about Oslo (and more generally Microsoft’s SOA plans) at TechEd. He reportedly said that we should expect a new “schema language” (which Mary-Jo thinks is “D”). What I want to know is what its relationship is with SML/SDM and SCA.

Mary-Jo might not know about SCA and SML but I know that David does. He wrote this white paper about SCA and an article arguing that “Microsoft Should Not Support SCA” (based on an a questionable assessment that SCA is only about portability). He and I also had a little back-and-forth about SCA, SML and Microsoft in the comments section of his post. Unfortunately, David hasn’t blogged about Microsoft’s SOA strategy for a while for us non-TechEd people.

In addition to Mary-Jo’s report, the only information I was about to quickly dig out about David’s presentation is this blog post on Microsoft’s Israel site. Looks like David gave the same presentation at TechEd Israel 2008. Anyone who understands Hebrew cares to translate the blog? Fortunately there is a two-minutes video (also available here) in which we can hear David talk (in English). During the second of the two minutes you’ll hear and see something that could come straight out of a SCA presentation…

For some reason, David’s TechEd Israel presentation doesn’t seem to be listed here and TechEd online tells me that “Featured videos are unavailable at this time”. That’s both for IT Professionals and Developers. But of course they forced me to install Silverlight before telling me that.

There were a few announcements relevant to the evolution of IT management over the last week. The most interesting is VMware’s release of the open-source (BSD license) VI SDK, a Java API to manage a host system and the virtual machines that run on it. Interesting that they went the way of a language-specific API. The alternatives, to complement/improve their existing web services SDK, would have been: define CIM classes and implement a WBEM provider (using CIM-HTTP and/or WS-Management), use WS-Management but without the CIM part (define the model as native XML, not XML-from-CIM), use a RESTful HTTP-driven interface to that same native XML model or, on the more sci-fi side, go the MDA way with a controller from which you retrieve the observed state and to which you specify the desired state. The Java API approach is the easiest one for developers to use, as long as they can access the Java ecosystem and they are mainly concerned with controlling the VMWare entities. If the management application also deals with many other resources (like the OS that runs in the guest machines or the hardware under the host, both of which are likely to have CIM models), a more model-centric approach could be more handy. The Java API of course has an underlying model (described here), but the interface itself is not model-centric. So what with all the DMTF-love that VMWare has been displaying lately (OVF submission, board membership, hiring of the DMTF president…). Should we expect a more model-friendly version of this API in the future? How does this relate to the DMTF SVPC working group that recently released some preliminary profiles? The choice to focus on beefing-up the Java-centric management story (which includes Jython, as VMWare was quick to point out) rather than the platform-agnostic, on-the-wire-interop side might be seen by the more twisted minds as a way to not facilitate Microsoft’s “manage VMWare today to replace it tomorrow” plan any more than necessary.

Speaking of Microsoft, in unrelated news we also got a heartbeat from them on the Oslo project: a tech preview of some of the components is scheduled for October. When Oslo was announced, there was a mix of “next gen BizTalk” aspects and “developer-driven DSI” aspects. From this report, the BizTalk part seems to be dominating. No word on use of SML.

And finally, SOA Software (who was previously called Digital Evolution and who acquired Blue Titan, Flamenco and LogicLibrary, in case you’re trying to keep track) has released a “SOA Development Governance Product”. Nothing too exciting from what I can see on InfoQ about it, but that’s a pretty superficial evaluation so don’t let me stop you. Am I the only one who twitches whenever “federation” is used to mean at worst “import” or at best “synchronization”? Did CMDBf start that trend? BTW, is it just an impression or did SOA Software give InfoQ a list of the questions they wanted to be asked?

I gave in to the temptation of a tabloid-style title for this post, but the resulting guilt forces me to quickly explain that it is speculation and not based on any information other than what is in the links below (none of which explicitly refers to SDM or SML). And of course I work for a Microsoft competitor, so keep your skeptic hat on, as always.

The smoke that makes me picture that SML/SDM fire comes from this post on the Service Center team blog. In it, the product marketing manager for System Center Service Manager announces that the product will not ship until 2010. Here are the reasons given.

“The relevant feedback here can be summarized as:

• Improve performance
• Enhance integration with the rest of the System Center product family and with the wider Microsoft product offering

To meet these requirements we have decided to replace specific components of the Service Manager infrastructure. We will also take this opportunity to align the product with the rest of the System Center family by taking advantage of proven technologies in use in those products”

Let’s rewind a little bit and bring some context. Microsoft developed the Service Definition Model (SDM) to try to capture a consistent model of IT resources. There are several versions of SDM out there, and one of them is currently used by Operations Manager. It is how you capture domain-specific knowledge in a Management Pack (Microsoft’s name for a plug-in that lets you bring a new target type to Operations Manager). In order to get more people to write management packs that Operations Manager can consume, Microsoft decided to standardize SDM. It approached companies like IBM and HP and the SDM specification became SML. Except that there was a lot in SDM that looked like XSD, so SML was refactored as an extension of XSD (pulling in additions from Schematron) rather than a more stand-alone, management-specific approach like SDM. As I’ve argued before (look for the “XSD in SML” paragraph), in retrospect this was the wrong choice. SML was submitted to W3C and is now well advanced towards completion as a standard. Microsoft was forging ahead with the transition from SDM to SML and when they announced their upcoming CMDB they made it clear that it would use SML as its native metamodel (”we’re taking SML and making it the schema for CMDB” said Kirill Tatarinov who then headed the Service Center group).

Back to the present time. This NetworkWorld article clarifies that it’s a redesign of the CMDB part of Service Center that is causing the delay: “beta testing revealed performance and scalability issues with the CMDB and Microsoft plans to rebuild its architecture using components already used in Operations Manager.” More specifically, Robert Reynolds, a “group product planner for System Center” explains that “the core model-based data store in Operations Manager has the basic pieces that we need”. That “model-based data store” is the one that uses SDM. As a side note, I would very much like to know what part of the “performance and scalability issues” come from using XSD (where a lot of complications come from features not relevant for systems management).

Thus the “enhance integration with the rest of the System Center product family” in the original blog post reads a lot like dumping SML as the metamodel for the CMDB in favor of SDM (or an updated version of SDM). QED. Kind of.

In addition to the problems Microsoft uncovered with the Service Center Beta, the upcoming changes around project Oslo might have further weakened the justification for using SML. In another FUD-spreading blog post, I hypothesized about what Oslo means for SML/CML. This recent development with the CMDB reinforces that view.

I understand that there is probably more to this decision at Microsoft than the SML/SDM question but this aspect is the one that may have an impact not just on Microsoft customers but on others who are considering using SML. In the larger scheme of things, the overarching technical question is whether one metamodel (be it SDM, SML, MOF or something else) can efficiently be used to represent models across the entire IT stack. I am growing increasingly convinced that it cannot.

Microsoft introduced an umbrella project called Oslo at their SOA and Business Process conference this week. There is very little information available but it seems to have two main components: improving the ability of the Microsoft platform to support SOA-style distributed applications and improving the use of models to develop and manage applications. At first sight there isn’t anything new. The SOA talk is similar to any number of “why SOA” presentations available from dozens of companies. And the modeling aspect is the same story that Microsoft has been pitching with DSI for years. The real news is that the two stories are being linked (at least at the marketing level, which is a starting point) and that the application development people have taken over the application modeling baton from the System Center group.

Over the last few years, I worked with people from System Center on different standards related to DSI, including SML which they see as the heart of the modeling effort. One of the things that kept me skeptical when hearing the DSI pitch, was to see the System Center team making announcement and promises about how SML would be central to the development experience in Visual Studio. I am pretty sure I know who’s the gorilla and who’s the chimp at Microsoft between Visual Studio / .Net Framework on the one hand and System Center on the other. The application model is too central to the developer experience for the Visual Studio group to not own it. It looks like it’s now happening and it’s a good thing.

The only content I could find on Oslo that’s not PR fluff is a report from Directions on Microsoft which mostly talks about incremental improvements to BizTalk. Towards the end, there is a small section about a “repository” that will “provide centralized storage of composite application components”. At that point I can’t help remembering the blog post from David Chappell about why it wouldn’t make sense for Microsoft to support SCA. Through comments in his post as well as a blog post of my own, I followed-up with the assertion that the application component model also plays a very important role for management. And at the risk of sounding self-congratulatory, the Oslo announcement seems vindicate that view. I see that David was a speaker at the Microsoft conference where Oslo was announced and he has very good insights into both the application developement and the systems management efforts at Microsoft. So hopefully he’ll soon have a white paper or a blog entry out to share some insights.

If you’re wondering what this means for the technical work that has been going on under the DSI umbrella so far, you can only read the tea leaves. It could be that the application development people adopted the whole SML/CML technology stack as promoted by their System Center colleagues and are going to use it as is. Or on the other extreme, it could be a complete reset that leads to the creation of a component model that is much less general and much more application-centric. Of course, no matter which one happens (or something in the middle), it will be presented as a perfectly smooth and controlled evolution of the DSI vision (get ready for some nice spin at MMS2008). If you are adopting SML because you expect Microsoft to base its application component model on it, you might want to wait a bit until more details emerge about Oslo. For example, after calling XSD “a schema language that attempts to be a floor wax, dessert topping, and personal lubricant all at the same time” you have to wonder whether Don Box would advocate to use SML (80% of which is XSD) as the most effective metamodel for an application component model…

Let’s end with this quote from the Directions on Microsoft report on Oslo, regarding application integration: “SAP and Oracle are better positioned in that regard, and so their customers will want to investigate these vendors’ composite application platforms along side Microsoft’s”. Can’t disagree with that. A good place to start this investigation would be the upcoming Oracle Open World.