I posted Cloud Services Continuum a couple of weeks back.  In that post I articulated a simplified view of cloud services and how they fit together.  This was simple by design — others had found this view useful, so I wrote it down.  I intentionally ignored some kinds of services, greatly simplifying the Infrastructure piece.  In this post I delve deeper into infrastructure services.  I’ll move on to platform next.

BTW: Stack is a more fitting word than continuum for various reasons, so I’m using that instead.  And a shout out to Matias Wolsky — check out his SaaS Taxonomy Map.

Infrastructure as a Service

In my earlier post, I defined IaaS to include provisioning of hardware or virtual machines on which one generally has control over the OS; therefore allowing the execution of arbitrary software. This definition isn’t really enough, because there are many other kinds of infrastructure.  Take a look at the services that are out there:

• connectivity / messaging services.  Examples: Microsoft BizTalk Labs and Connectivity Services, Gnip.
• identity services. Countless OpenID identity providers, again the BizTalk Labs Identity Services.
• data storage.  Examples: Amazon’s S3 and SimpleDB, Microsoft SQL Server Data Services.

One might argue that together these services create a “platform” — and they get close — but since none of these host general user-written code, they don’t quite get there.

Then, of course, there is flexible machine provisioning like Amazon EC2.  These are definitely infrastructure — where the platform is the OS, Web servers, and other software.

Calling this all IaaS is fine — it is all infrastructure — but, maybe we should further divide these:

• Virtual Hardware Infrastructure
• Storage Infrastructure
• (Other) Infrastructure Services

Granted, these names need some work, but I think the categories are useful.  And I won’t make them into acronyms because I think we have enough of those.