SEOUL• • In a darkened "war room", dozens of South Korea's brightest college students are practising hacking each other as part of a government programme to train them to battle some of the world's best - the shadowy techno-soldiers of North Korean leader Kim Jong Un's regime.
To build its defences, President Park Geun Hye's government has enlisted 120 of the country's most talented young programmers, offering full scholarships in return for seven years of military service.
While the hackers of the Kim regime may be best known for their link to last year's attack on Sony Pictures, their primary target remains South Korea, with the two countries technically still at war more than 60 years after the conflict that sealed their division.
The urgency to train "white", or ethical, hackers is rising as industrialised nations try to safeguard digital information vital to national security and infrastructure.
South Korea's experience fending off the North has made the country a global player in cyber defence but mitigating future damage still remains a challenge for Seoul as the North's attacks become more sophisticated.
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I've never met or talked to my North Korean rivals. So there's no point in being intimidated prematurely. We train because we enjoy training and that's how we're going to defend our nation.
"HYVA", a 21-year-old junior in the hackers' college programme who says he is not cowed by the prowess of his opponents
The technology ministry funds additional training for some of the students who receive the scholarships to Korea University's national cyber-defence department, which will produce its first batch of graduates next year.
The college programme is part of a broader build-up. The government is doubling the size of its cyber command to 1,000 people and raised spending on information security by almost 50 per cent to 250 billion won (S$307.5 million) between 2009 and 2015.
North Korea began to train its cyber warriors while developing nuclear arms in the early 1990s and now commands 1,700 "highly skilled and specialised hackers", Mr Cho Hyun Chun, chief of South Korea's Defence Security Command, said in July, calling North Korea a "global cyber power".
Ironically, the isolated country allows Internet access to only a small portion of its population.
Pyongyang's elite cyber unit was set up to focus on attacking military, economic and other key facilities in the event of war, said Mr Kim Heung Kwang, who taught computer science at a university in North Korea before he defected.
"Hackers were a cost-effective way to neuter South Korea's key facilities in the event of war," he said.
The North's cyber prowess took the South by surprise and, in 2009, a suspected North Korean cyber attack paralysed US and South Korean government websites, prompting Seoul to set up a cyber-defence command the following year.
The initial attacks were more disruptive than destructive until 2013 when North Korean hackers hit South Korean broadcasters and banks, paralysing 32,000 computer servers, thousands of cash machines and Internet banking.
It was "pretty sophisticated", said "Hyva", a 21-year-old junior in the hackers' programme who has examined the North Korean code used in the attack. His name is classified to prevent him from being identified by North Korea.
He turned down an offer from a medical school to join the programme, which offers scholarships worth 38 million won over four years and a monthly stipend of 500,000 won.
Hyva said he is not cowed by his opponents.
"I've never met or talked to my North Korean rivals," he said. "So there's no point in being intimidated prematurely.
"We train because we enjoy training and that's how we're going to defend our nation."