The Defense Department’s head of cyberspace operations said it built a cloud computing system with the help of industry and pushed it into the public realm for testing.

U.S. Cyber Command (CYBERCOM) chief Army Gen. Keith Alexander said last week the command had the cloud system, which he called “Cumulo,” tested in the “open ware community” so that it could develop encryption. CYBERCOM did not return phone calls Monday for comment on Cumulo.

“The reason we did that is…when you push it out into the open community, everyone can now beat that up and it gets better and we all benefit,” Alexander said at the GEOINT 2012 conference in Orlando, Fla. “What we want is the encryption that you put on it. That’s something that we’re going to treat very sensitive, (that) the open ware that we had now has that secure layer. So that comes back to that defensible architecture, have that secure layer there.”

Earlier in his remarks, Alexander advocated using a “thin, virtual cloud environment” to create that defensible architecture.

“I’m an advocate of the cloud,” Alexander said, referring to Cumulo. “We wanted to add in a couple other layers to that cloud. One, we wanted (it) to be secure and we wanted real-time tipping and cuing capability. Then we wanted all the other attributes that you have in the cloud that Google cloud and all the rest of them do.”

Google (GOOG) Monday deferred questions about Cumulo to CYBERCOM.

Alexander also said during his speech CYBERCOM has to “train (its) people better” and that training CYBERCOM is his “top priority.”

“Why is that?” Alexander asked. “If someone is trying to get after us, you want the top gun folks in this space ready to go and be able to secure the country. So we have to have a force that does that and that’s the approach we’re taking.”

Alexander said other pertinent areas for CYBERCOM are command and control and chain of command. Alexander is also National Security Agency (NSA) director.

“How do we work cyber space between Cyber Command and the other combatant commands?” Alexander asked. “What’s the chain of command for Cyber Command and NSA? (Those are) some of the issues that we’re currently working (on) right now.”