The major barrier of cloud computing

It has been a few years since people started talking about "cloud computing". But it seems not many people think about the problem from business perspective.

As a normal business corporation, what do they need?

Let's say there are 10 systems in a company, some are running on windows, some are running on UNIX or Linux. Of course these systems talk to each other to provide high quality services.

Now, CIO believes it's good timing to move part of them into "cloud". He wants to move 2 systems into Microsoft cloud, 2 systems into Google cloud, 2 systems into Amazon, and leave the rest on-premise servers. (We don't want to put all eggs into one basket, do we?)

How can we achieve that? Technically say, it's no possible (at the moment).

As I know, "OAuth" is becoming the standard user authentication protocol on Internet. So, different clouds are bound to different user profile source, such as Google account, Outlook account, etc.  Can I use Google account to access the data stored in Microsoft cloud?

To resolve this problem, as the first step, we need some organization similar to ICANN, but it manages user identity instead of IP address. It can do the user authentication and then issue "user security ticket" to all the clouds on Internet. All data access permissions should be based on that "user identity". Without it, the clouds are isolated from each other.

How long it would take to set up such an organization? I will be surprised if it start to work in 10 years.

Ok, let's go for private cloud. We have our own "domain controller" there, and don't need to worry about this headache.

(Please leave comments here if you have other thoughts.)

[20121016 Update]

People often think "Pay-as-You-Go" is one of the major advantages of cloud computing, so the cloud computing could be treated as "service" instead of "software". However, although we can easily switch service provider in some areas, such as electricity and ISP, can we do the same switch on cloud computing?

If we cannot switch cloud provider, is it really a smart choice to move to cloud computing?