Using photons to transmit quantum keys to satellites ‘on the fly’

The Canadian Space Agency is working with a commercial entity to change the game in secure global communications.

According to a media advisory from the Canadian Space Agency, it has supplied QEYnet, a commercial enterprise who say their mission is to “build the world’s first Quantum Key Distribution (QKD) network” with funding for its successful demonstration of “quantum key distribution technology in space.”

According to QEYnet CEO Cordell Grant this will offer “effectively perfect encryption” of sensitive information. Furthermore, QEYnet will use a series of photons to transmit the key of encrypted messages over vast distances. Grant thinks QEYnet’s use of quantum key distribution will ensure secure encryption of information even after quantum computing has arrived.

“To advance the development of technology that could guarantee the privacy of Canada’s public, private, and commercial data,” reads the advisory, “the Canadian Space Agency has awarded a $1.4 million contribution to QEYnet for the demonstration of their quantum key distribution technology in space.”

According to QEYnet, QKD is a technology that uses quantum technology to make encryption keys for computers and software that are “completely impervious” to eavesdropping, making the technology much more secure for important tasks like finance, communications and more.

“We didn’t invent quantum key distribution,” said Grant. “Quantum key distribution has been around for quite some time. I think it was first conceived sort of back in the early ’80s. If you can exchange individual photons, and the single particles of light, then you can use that to basically do effectively, perfect encryption. The challenge has always been, ‘How do you exchange single photons at a scale that is useful to anybody?’ … The challenge has been, ‘How do you implement a way to do this at global scale?'”

So, Grant and his team at QEYnet devised a way to make it possible via satellite.

“That’s where satellites come into the picture,” said Grant. “Rather than try to send single photons around the around the world over fiber optic cable, what you can do instead is do an exchange of photons between the ground and an orbiting satellite, and then that satellite is going to continue in its orbit, and it can do the same thing with another location on the ground, and act as sort of an intermediary between those two locations while still preserving the theoretically perfect security.

“The challenge, you know, up to now is just sort of been, ‘how do you actually build that satellite technology?’ which is obviously somewhat technologically challenging to do,” said Grant. “I guess the innovation in our case is how you would exchange keys between two locations on the ground using a satellite. I think the innovation from QEYnet was really recognizing that satellites themselves also need security.”

Grant describes the existing paradigm of quantum key distribution in satellites.

“The sort of paradigm in the space industry has been that it’s actually really hard to update the encryption keys on your satellite securely,” said Grant. “So, what people [in the space industry] are doing is, in much the same way that satellites launch with all of the fuel that they’re ever going to have … they’re also launching with all of the encryption keys that they’re ever going to have. This is a risk, right? So, what do you do if you just launched a $100 million mission and then soon after you find out, ‘Oh, actually, our keys were compromised, and maybe all of our communications will be compromised?’”

“Those can never be changed,” he continued. “So, what our innovation is, is using [quantum key distribution] to build a device that could help get you out of that paradigm and allow you to securely read through your satellites so you can, first of all, have better confidence in your cyber security of those satellites, but also enable other sort of novel architectures onboard a satellite for example, where maybe you could put the [quantum key distribution] system on the payload of the satellite.”

The release from the CSA notes that its funding contribution will allow QEYnet to test a low-cost QKD technology in space, which will pave the way for “secure global communications and the foundation of future quantum networks.”