Introducing Oracle's new Exalogic Elastic Cloud machine, Larry Ellison opened his remarks by saying that cloud computing has many definitions, and he cited Amazon.com and Salesforce.com as examples of profoundly different cloud approaches. And then he unloaded on Salesforce.com for "commingling" customers' data and offering "a very weak security model.""Maybe the two most well-known examples of cloud computing represent opposite ends of the spectrum," Ellison said in underscoring his contention that cloud computing means many different things to many different people. "On the one hand you have Salesforce.com, a very successful application on the Internet, and a lot of people call that cloud computing-you access the application on the web, it's 10 years old, and it's SaaS technology, and some people say that's cloud computing."

As a counterpoint, Ellison then described Amazon.com's EC2 as a hardware/software platform for building and running applications and using Linux, Java, Oracle database, MySQL, and other prominent technologies in a highly virtualized environment that can run a wide variety of applications.

"The technology is virtualized so each customer has its own separate, secure, and virtual environment with fault isolation, so most systems failures affect only one customer," Ellison said as even I began to see which way he was tilting.

But Salesforce.com's SaaS model, he said, is totally different-and Ellison did not mean "different" as in "good," even though he was an early and significant investor in the company and has maintained some level of marketplace collaboration with Salesforce.com and CEO Marc Benioff. (For example: Benioff speaks on Wednesday morning at Oracle Open World.)

"Salesforce.com is really one or two applications on the Internet," Ellison said. "It's basically just a salesforce-automation app on the cloud, and is primarily just SaaS apps with a very limited platform.

"It is not virtualized; in fact, it's just the opposite," Ellison said. "With Salesforce.com, hundreds of thousands of customers have to commingle their data to use these applications, so GE's data is in there mixed up right next to Siemens' data and so on-and the result is that really it is a very weak security model."

Ellison went on to say Salesforce.com lacks fault-tolerant architecture, is not secure, and is not elastic. "You've got many customers and their data just coexist in the same database, and since there's no fault-isolation, a system failure brings down many customers. And, it's not elastic."

But then Ellison, showing his new-found magnanimity toward different people's desire to embrace different concepts of what cloud computing is or is not, added this: "But, hey-if you want to call that cloud computing, please do."

Marc Benioff's always got intriguing things to say, and after the portrayal of his company's security capabilities offered by his friend Larry Ellison, Benioff's talk tomorrow should be even more intriguing than usual.

RECOMMENDED READING Global CIO: Will Larry Ellison Launch Bidding War With IBM For Netezza? Global CIO: Oracle Launches 'Cloud In A Box' And New Cloud Business Global CIO: At Oracle Open World, Oracle Commits To Cloud Computing Global CIO: Larry Ellison's Top 10 Priorities At Oracle Open World Global CIO: Oracle's Larry Ellison Declares War On IBM And SAP Global CIO: Larry Ellison's Acquisition List: Who's #1?