(CNN) – The communication hotline between North and South Korea is warming up.
The two neighbors hadn’t talked to each other on it for nearly two years, now they’ve spoken five times in just two days.
Many see it as a positive development.
The hotline is a mystery to most folks. It’s located in the border village of Panmunjom.
The settlement spans both North and South Korea within the DMZ, one of the most heavily guarded borders on earth.
The official title of the hotline is the Panmunjom Communications Channel. It’s a political lifeline between the two Koreas that are still technically at war.
If you’re calling the North from the South Korean side, you use the green phone. When North Korea calls the South, they pick up on the red phone.
“It is not about North calling South and South calling the North,” said John Delury, an expert on North Korean affairs at Yonsei University. “The two are sending positive signals back and forth, and they are creating momentum which can lead to some breakthroughs.”
Almost any breakthrough is considered big, given the stakes.
The buildings on either side of the border, where the phones are located, are only about 60 feet apart from each other.
The first two channels were connected in 1971. Over the years, the number of different communication channels has grown to 33.
But until this week, North Korea hadn’t answered any of them since February 2016.
Two liaison officers have been calling every day at 9 a.m. when they get to work and then again at 4 p.m. before they left. All day they waited by the phone in case it rang.
Now that it’s being used again, there’s a measure hope during simmering international tensions over North Korea’s nuclear weapons program.
“It's not a matter of who initiates what,” Delury said. “It is they get a positive dynamic going, and that's what we are seeing now.”
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