North Korea Cyberwarfare: What We Know About The DPRK's 1,800 Hackers After The Sony Attack

North Korea's alleged hack of Sony Pictures Entertainment over the movie "The Interview" has thrust the DPRK's ongoing cyberwarfare campaign into the public consciousness, but there's still a lot the world doesn't know about the capabilities of Kim Jong Un's regime. Here's what we do know:

How many hackers does North Korea employ? Jang Se-yul, a North Korean defector who says he is a former hacker for the Kim regime, told CNN the DPRK employs 1,800 hackers in its largest cyberwarfare unit, Unit 121. Unit 121 and other, smaller cyberwarfare units reportedly work under the umbrella of the DPRK’s General Bureau of Reconnaissance. North Korean hackers live and work all around the world. Unit 121 is reportedly “tasked with disabling command control and communications,” in South Korea in the event of war, while Lab 110 specifically targets South Korean telecom infrastructure, according to Egle Murauskaite, a specialist with the U.S. National Consortium for the Study of Terrorism and Responses to Terrorism.

Who are the hackers? Because it’s a relatively cheap offensive endeavor -- compared to pursuing nuclear weapons, for example -- North Korea has focused heavily on its cyberwarfare capabilities. The hackers, who are often handpicked from North Korean universities and begin training around the age of 17, are paid well, and their families are elevated to high social status and rewarded nearly as much as the hackers themselves, according to Jang.

What is their connection To China? North Korea’s big neighbor ally is a hub of hacking activity and North Korea has been tapping into it for years. North Korea and China even jointly run a hotel to house North Korean hackers living and working in China. Those hackers are trained by Chinese and Russian experts. North Korea reportedly connects to the Internet mostly via Chinese networks, so Chinese authorities could potentially cut the DPRK off. The Obama administration asked China to help reduce or eliminate North Korean capabilities, but it is unclear whether China will honor the U.S. request considering the two countries often target each other in cyberspace.

What other attacks have they perpetrated? North Korean hackers have been connected to dozens of attacks over the last 10 years. DPRK hackers often target the South. They have shut down numerous South Korea websites with direct denial of service attacks that flood a website with requests to the point where it collapses under its own weight. They’ve stolen millions of dollars by cheating South Korea’s favorite hobby: computer games. In one orchestrated attack in March 2011, North Korean hackers shut down 40 South Korean websites, including the presidential Blue House site, the National Intelligence Services and two massive search engines, according to the New York Times.

What Is North Korea Really Capable Of? “In the history of cyberconflict we’ve never really found any example of a hack that was strategically significant on the scale of which many have warned,” said Jason Healey, director of Cyber Statecraft Initiative at the Atlantic Council. “We’ve been warning about a digital Pearl Harbor since 1991 and it hasn’t happened.”

The Sony hack wasn’t a particularly sophisticated attack and doesn’t demonstrate a strength capable of causing real harm, Healey said. He said he doesn’t think North Korea had to employ outside hackers to get the job done and it probably cost Pyongyang $1 million to $4 million to execute.

“Maybe they could turn the power off in South Korea, but they have artillery, missiles and chemical weapons so their cybercapabilities aren’t necessarily the scariest bit out of that arsenal,” Healey said.

What Does The Sony Hack Say About North Korea? While not a strategically important hack, the Sony hack became a presidential issue when Sony decided not to release the movie, legitimizing it as a successful attack on free speech, Healey said. It also set a precedent that could encourage other countries like China and Russia to go after American interests.

“If China and Moscow see how this is successful, I mean what happens when you pay the kidnappers?” he said.