Especially with the increased adoption of cloud-hosted applications and IT computing services, the notion of a countrywide Internet access blackout is bound to rattle IT executives.

And it should, according to Eric Paulak, a Gartner analyst. "This scenario isn't so far-fetched. It's just that you don't necessarily hear about it," he said in a phone interview.

Virtually every country's government reserves the right to temporarily nationalize and control what's considered critical infrastructure, which usually includes mobile networks, fixed-line telecommunications and Internet backbone systems, Paulak said.

Governments can invoke that right during national emergencies, whether they be natural disasters, terrorist attacks or any other incident that qualifies as such under a country's legal code.

"Theoretically this can happen anywhere, although the likelihood is pretty low," Paulak said. "However, because of that legal authority most countries have, the Internet, the mobile networks and the fixed-line phone networks could be cut off."