This week, news broke that North Korea and South Korea would be holding their first direct negotiations in more than two years, and on Wednesday, the countries reportedly opened a dormant hotline between the two countries. Since then, the press has circulated photos of that hotline, which revealed a retro-looking telephony setup that looks like something from a movie shot in the 80s and set in 2050. We were enchanted: What was this strange machine?

The computer that the South Koreans use to communicate across the demilitarized zone is encased in wood and mounted on a long desk that also holds a fax machine and a more traditional telephone handset. The computer’s hardware is strikingly symmetrical, with parallel optical disk drives, USB ports, speakers, telephone handsets and two mysterious gray objects mounted to black casing. Two digital clocks on top of the computer display different times.

Strangest of all, perhaps, is what appears on its small display: the telltale rolling hills and deep wispy sky of “Bliss,” the default wallpaper for Windows XP, Microsoft’s iconic 2001 operating system. (Another photo of the console taken on the same day shows a different background, but with the Windows XP taskbar.)

Dag Spicer, the senior curator at the Computer History Museum, said that the device appeared to be a plain vanilla PC mounted in a custom wood-grain cabinet. Rugged custom cabinets are not uncommon in military computing applications, Spicer said, though militaries don’t usually use wood. Spicer was also puzzled by the two silver objects between the phones.

“I think it’s just a homebrew system,” he said. “They’ve taken a Windows computer and they’ve added phones.”

If the operating system is indeed Windows XP, Spicer said, it raises a host of security concerns, since Microsoft stopped issuing regular updates for the system in 2014. Though it’s not clear whether the computer is connected to the internet, the out-of-date technology could leave the crucial channel of international communication open to attackers.

Roger Anderson, a telephony consultant in California, said that the software open on the screen may be X-Lite, an internet telephony or voice-over-IP (VOIP) program made by Vancouver software company CounterPath. CounterPath did not respond to a request for comment.

“I can’t imagine they’d be using VOIP for something that critical,” Spicer said. “It’s a little frightening to think about.”

Martyn Williams, who writes for 38 North, a blog dedicated to analysis of North Korea, also worried about the prospect of using an outdated operating system to facilitate delicate international communications.

“There's obviously a computer housed inside that wooden enclosure,” he wrote in an email. “Why the special case? Who knows, but perhaps it’s just to reinforce or highlight it as a dedicated unit and not something people should be using for other purposes?”

According to a BBC report this week, the green handset makes outgoing calls and the red phone receives incoming ones. Every day since 2016, when relations between the two countries disintegrated, a South Korean official has used the green one to place a call to North Korea. This week, for the first time, North Korea picked up. The two nations have now tentatively scheduled talks in the border village of Panmunjom this coming week.

If the wooden computer fails, South Korea may have a backup plan: In a tray next to the wooden computer is a flip phone.