An employee of French National Agency for Employment (Pole Emploi) works simultaneously on French and German agencies for employement internet sites, at the joint German-French job center office in Kehl, Germany, on the French-German border near Strasbour
An employee of French National Agency for Employment (Pole Emploi) works simultaneously on French and German agencies for employement internet sites, at the joint German-French job center office in Kehl, Germany, on the French-German border near Strasbourg, November 13, 2014. The center, the first of its kind, joining French and German Employment Agencies, was inaugurated in February 2013 and is due to facilitate the search for jobs for German and French unemployed persons in both countries. REUTERS/Vincent Kessler REUTERS/Vincent Kessler

North Korea on Monday suffered a massive internet outage that lasted nine hours. But experts were quick to draw the disruption was not in any way related to the country's cyber security was with the United States. Instead, the attack was just all in a day's work for hackers.

Dan Holden, a director at network defense firm Arbor Networks, in a blog post said they have seen North Korea's Internet already getting attacked "over the last few days." A closer scrutiny revealed the hackers targeted government owned and operated sites such as Naenara, the official Web site for the DPRK, and the Kim II Sung University, the first University Web site ever hosted by North Korea.

As expected, the hacking and eventual disruption of North Korea's Internet was being attributed to the United States, which last week vowed to launch a proportional response to a cyber-attack on Sony Pictures. The latter made a comedy about North Korean leader Kim Jong-un, now the cause of troubles between the two nations.

But Holden maintained the attack didn't emanate from Washington. "Much like a real-world strike from the U.S., you probably wouldn't know about it until it was too late. This is not the modus operandi of any government work," he wrote.

He said hackers rendered a "denial of service attack" on North Korea, described as "an intentional network traffic jam." Arbor Networks, which tracks Internet attacks around the world, said it noticed the denial of service attack as having started on Thursday, initially targeting approximately 1,000 North Korean Internet addresses. Attacks then crested over the weekend.

Hackers known as the Lizard Squad took credit of the denial of service attack. POLITICO had described the group as one with a "history of launching sophisticated denial of service attacks, including against the Sony PlayStation network."

Xbox Live & other targets have way more capacity. North Korea is a piece of cake.

— Lizard Squad (@LizardUnit) December 22, 2014

North Korea #offline

— Lizard Squad (@LizardUnit) December 22, 2014

Lizard Squad may have been victorious on this one, but Holden said the disruption hardly achieved anything at all. North Korea maybe high-tech, but it doesn't allow access to the worldwide web. It is not known how much bandwidth flows into North Korea, but Matthew Prince, CEO of content delivery network provider CloudFlare, said it's likely quite small.

Prince told POLITICO he believed it was a teen who did the denial of service attack. "It's probably risky to speculate that that attack is being launched by any state-based entity," he said. "It's much, much more likely that it's some 15-year-old in a Guy Fawkes mask."