Friday, December 14, 2007

Microsoft forecast: partly cloudy

In a previous post I asked Where is the Microsoft cloud? That is, where is the Microsoft competitive offering to Amazon's AWS, for example.

So far, I've found mostly hot air. BizTalk Services is interesting, but still very much in the early stages. Certainly worth keeping an eye on. But branding it under the BizTalk name seems very odd - these are fundamental services like authentication, access control, & connectivity - and not tied specifically to BizTalk.

I have to say that I'm not getting the great sense of urgency from Microsoft about cloud computing that Nick Malik's "Microsoft is coming" bravado suggests.

Now, Microsoft is certainly talking a lot about cloud computing - has been for the last 6 months. From a NetworkWorld article:
Microsoft also plans later this year to launch Version 1 of a 12- to 24-month project to create Windows Live Cloud Infrastructure Services, Web-based services such as directory, identity and storage. The operating system services target companies and developers, who will wrap them around their applications, such as tapping an online directory service to generate a Kerberos ticket that a user would present to gain access to an on-premises or service-based application.

Which all sounds like goodness. But that article was written in July. End of the year is only a couple of weeks away. Did I miss that Version 1 release announcement? Maybe they were talking in Friedman Units.

Can a project of this magnitude be even only 24 months away when Cloud Infrastructure Services is still just a Microsoft research project with a rather nebulous vision?

And if putting announcements with titles like "Microsoft Does Have a SOA Strategy" on your main SOA page is meant to inspire confidence, well...

Thursday, December 13, 2007

When a service isn't the answer

I was discussing a rather involved design issue with a colleague recently, and as I pulled away from the diagram I had drawn out as we were talking it over, I said, "Surely someone else has already dealt with these issues. There must be a 3rd party service we could use that would handle all of this for us."

"There is," my colleague said, "but they'll charge for every transaction, which can't be written off. If we build it ourselves then the costs are a capital expense and the cost can be depreciated."

And so it goes.

Monday, December 10, 2007

Distributed state management for ASP.NET

The more I delve into distributed architectures, the more I'm feeling like Microsoft just isn't providing much of a path forward to scalable distributed systems. Case in point: state management.

By default, session state in ASP.NET is stored in the web server's memory. To share state across servers - which you would want to do in a server farm - you need to store it in SQL Server or in the .NET state service. This is fine for small solutions, but once you bump up against the need to partition state across many servers or multiple hosting locations, things start to get complex and expensive.

Now, it seems the Java folks have worked through these issues already. Here I'm thinking of Space-Based Architecture and more concretely JavaSpaces.

Perhaps I'm oversimplifying, but wouldn't JavaSpaces be a perfect place to store session state in a distributed system? Data in a JavaSpace is persistent, atomic, distributed, & fault tolerant.

There isn't a .NET equivalent of JavaSpaces. But, MS does provide SessionStateStoreProviderBase and the ability to choose a custom provider for session state.

So, here's the recipe as I see it:
  1. Set up a JavaSpaces instance on a Linux cluster (probably using Blitz to start out with)
  2. Write a custom state provider that inherits from SessionStateStoreProviderBase and implements the necessary JavaSpaces methods. (Working out the bridging between .NET & JavaSpaces, of course. There is a tantalizing page called Using JavaSpaces from .NET - but it relies on a commercial product to accomplish this.)
  3. Change your ASP.NET web.config to point at your new custom state provider.
These don't appear to be big hurdles to overcome, and it seems like a nice little open source project.

(In the interest of due diligence, I did run across 2 commercial software products that seem to be solving this kind of problem: ScaleOut and NCache. But for a server farm of 20 servers, you're looking at something in the neighborhood of $30K, not including the cost of the Windows Server licenses + ongoing annual maintenance fees. There is also GigaSpaces, which provides hosted JavaSpaces and has a .NET API, but is also expensive.)

Here are some links I found useful in my research:

Tuesday, December 4, 2007

Where is the Microsoft cloud?

I've been doing heavy research lately into scalable distributed systems, and Amazon's S3 and EC2 are front and center in my brain as I'm working my way through the literature.

Amazon's AWS and now IBM's BlueCloud are out in front with cloud computing offerings. Google may or may not be planning something akin to S3 with Google shared storage combined with APIs.

In the midst of my research, I saw that Microsoft has a codename - Oslo - for their next iteration of SOA tools. And so the obvious question (to me, at least) is: where is Microsoft's cloud computing offering?

Well, looks like BizTalk Services may be Microsoft's response. Charles Young has an overview of his early experiences with it.

Looks like I have more research to do...