Both government and business agree that sharing data is critical to fighting cyber threats to the nation's critical information and infrastructure resources.

One hang-up the private sector has found when sharing data with the U.S. government is that the information most useful to companies is classified, which means they don't have access to it.

As a result, you'd think a program like the Enhanced Cybersecurity Services (ECS) initiative -- designed to improve the flow of classified information to businesses -- would attract companies like iron shavings to a magnet. That hasn't happened.

The ECS, under another name, began in the U.S. Department of Defense and was moved earlier this year to the Department of Homeland Security after President Obama issued an executive order on information sharing between government and business. That order called for the development of a program for furnishing "classified cyber threat and technical information from the Government to eligible critical infrastructure companies or commercial service providers that offer security services to critical infrastructure."

[See also: Threat intelligence: Why it's about sharing more data]

"The administration said, this has worked well within the defense industrial sector, let's open it up to everybody we classify as critical infrastructure providers," Andrew Braunberg, research director for NSS Labs, said in an interview.

On its face, ECS sounded like a good idea to business because it made information sharing between government and the private sector a two-way street.

"A lot of the problem with information sharing is that it's one-way," Braunberg explained. "The government wants private sector data, but they don't always return good data the other way."

With ECS, good, actionable data -- anything from virus signatures to malware alerts -- would be flowing to companies without their having to return the favor.

However, since its transfer to DHS, ECS has failed to expand beyond the original 17 defense firms participating in it, although 54 companies expressed interest in the initiative. "None of them have signed on because once you start looking at the costs involved, it starts to look less like a free lunch," Braunberg said.

Part of those costs include obtaining security clearances for employees, something that goes with the territory of being a DOD contractor. "For the defense guys, this is a no brainer," Braunberg observed, "but once you get outside the defense base, you don't have guys on staff that have those clearances."

Security clearances can be a thorny problem for many high-tech companies. "You may have foreign nationals working for companies, protecting their networks, but that's a show-stopper for security clearance," John C. A. Bambenek, a handler at the SANS Internet Storm Center and president of Bambenek Consulting, said in an interview.

"As a matter of course, we don't grant security clearance to people who are not U.S. citizens," he said.

Moreover, there are doubts from some companies about how actionable the data they receive will really be. "Once you get the data, how much of it can be disseminated within your organization beyond this bubble of classified folks is also going to be problematic...," Braunberg said.

Just because the government considers information classified doesn't mean it's secret. "A lot of this general information is over-classified to begin with," Bambenek said.

"There are times that I've picked up on things that I later learned through the grapevine are being disseminated as classified," he continued. "If I had security clearance, that would complicate my ability to discuss things that I found through open-source intelligence gathering that later became classified."

While ECS hasn't caught fire yet, it's still too early to judge its success or failure, noted Greg Garcia, founder and principal of Garcia Cyber Partners and a former DHS assistant secretary for cybersecurity.

"DHS is just getting this off the ground," he said in an interview. "If someone shows you a shiny new watch, you want to assess whether it keeps good time, is reliable and is cost effective. The cost-benefit analysis is what companies are undertaking right now."

Another development may be giving companies pause: The recent controversy over government snooping. "There's certainly a lot of people taking a step back and looking at how involved they want to be in light of the PR heat over PRISM," Bambenek said.

Garcia added: "Might there be companies looking at ECS and see the PR concerns around PRISM and slow down their movement? Maybe so. They may want to lay low. But this will pass and then the question to be asked and answered will be, 'Is this program going to be cost effective for the companies?'"

This story, "Businesses Slow-Walk Classified Data-Sharing Efforts with Feds" was originally published by CSO .