Quantum networking takes off… into space

Boeing announced today that its quantum satellite, named Q4S, will launch in 2026 to demonstrate quantum entanglement swapping capabilities on orbit.

When it comes to space-based quantum communications, only China has a satellite up in orbit. In fact, China’s first dedicated quantum communication satellite went up in 2016. Europe and Canada have plans to launch satellites in 2025 or 2026. And with Boeing’s announcement – made at the Quantum World Congress being held just outside of Washington, D.C.– the United States is now joining the club.

Boeing is “taking on the challenge of entanglement swapping in space,” says Jay Lowell, chief engineer of disruptive computing, networks and sensors at Boeing.

“This demo aims to solidify Boeing’s role as a pioneer, pushing the boundaries of what’s possible,” Lowell says. “Boeing is doing much more than participating in quantum research. We are leading the way to operationalize and scale quantum technologies for global applications.”

According to Boeing, space-based quantum communications has applications in numerous commercial, civil, and military sectors. The technology has already been shown to work in a laboratory, and the 2026 launch will demonstrate a space-hardened version.

Quantum communications rely on entanglement for absolutely secure communications, but photons decay quickly over long distances. Sending a beam straight up to a satellite in space, then back down to the destination on Earth, could potentially solve some problems – as long as the satellite is able to relay the signal back without breaking the entanglement. That’s what Boeing’s “swapping” technology is designed to do.

Combining shorter-distance, ground-based quantum networks that piggyback on existing fiber infrastructure with satellite-based relays can help lay the groundwork for a global quantum Internet.

“Achieving a global-scale quantum network requires substantial work,” says Lowell. “First, we need to establish and demonstrate a robust quantum communication protocol to ensure the proper dissemination of information across network links – which is what the Q4S mission addresses.”

Use cases for quantum networks

Quantum networks have three main use cases, says Jim Ricotta, CEO of Aliro Quantum Technologies, a quantum networking software company.

They are not expected to replace standard communications in the near future, since they don’t have enough bandwidth to carry any significant amounts of traffic. Instead, they’re expected to be used for quantum key distribution, to network quantum computers, and to support quantum sensors.

There are two types of encryption. Symmetric encryption – where the same key is used to both encrypt and decrypt – is the strongest, and it’s expected to continue to be safe for a long time. The second type, asymmetric encryption, involves different keys for encryption and decryption. Asymmetric encryption is considered to be vulnerable to quantum computers, and there is a concern that adversaries are already vacuuming up encrypted communications with plans to decrypt them as soon as the quantum computers get good enough.

One solution to this problem is to switch to new, quantum-safe encryption algorithms, but that still relies on math for security, says Ricotta. Another solution is to use the laws of physics to guarantee security, he says.

Aliro is already working with an intelligence agency on one such project, Ricotta says, and companies in sensitive sectors like finance and energy are also interested. Another Aliro customer, EPB Quantum Network, has a working quantum network in Chattanooga, Tenn.

Another use case is to network together small quantum computers into larger computing clusters. Aliro is announcing an agreement today with the U.S. Air Force on a project to do just that, Ricotta says.

A third use case for quantum networks is to improve the functionality of a quantum sensor. If, say, a quantum sensor is used as an alternative in case something happens to the GPS system, a sea vessel might have quantum sensors at each end of the ship for greater accuracy. These sensors would be connected with a quantum network.

“Our country is waking up to the fact that this is a super important technology,” says Ricotta.

This year so far, according to Crunchbase, quantum computing startups have raised $1.4 billion, which is almost double the $777 million for all of last year. And, in June, for the first time ever, Gartner included quantum networking in its hype cycle for enterprise networking, in the “innovation trigger” phase.

But, according to McKinsey, the US lags far behind other countries in public investment. The Chinese government has invested $15.3 billion in quantum technology as of 2023, followed by Germany at $5.2 billion, the UK at $4.3 billion. The US is in fourth place with $3.8 billion.

Last week, the US government’s National Quantum Initiative Advisory Committee released a report calling for increased federal investment in quantum networking. “Quantum networking capabilities will play a role in U.S. economic prosperity and national security,” the report says.

“That’s why it’s important to have the quantum initiative reauthorization get through Congress,” says Ricotta.

In 2018, the National Quantum Initiative Act allocated $1.2 billion for quantum research – but that act expired in 2023. The National Quantum Initiative Reauthorization Act is currently working its way through Congress and would allocate $3.6 billion for quantum research over the next five years.

Use cases for quantum networks

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