Extending the reach of quantum key distribution (QKD) beyond the Earth’s atmosphere is an important step towards a more secure future. It is a way to solve the limited range a photon can travel without compromising its integrity.
While the total route length of fiber optic cables on the planet exceeds 27,000 kilometers, or almost 17,000 miles, photons can only travel a distance reaching up to 421 kilometers (262 miles) as of today.
However, instead of finding ways to extend the traversal distance further, this new approach of incorporating satellites proves to be a reasonable solution.
Let’s explore how QKD is implemented in space and why it is gaining popularity as the ultimate form of quantum security.
A Brief Overview Of Quantum Key Distribution
The emergence of quantum computing has had an immense effect on the world today. Its computational power dwarfs conventional supercomputers – opening up new possibilities for many industries.
However, with better computing power, quantum computers also enable swift solutions to complex mathematical problems like the ones used in traditional encryption.
The inevitable effect is that quantum computing will soon make all conventional key distributions obsolete.
QKD seeks to remove the math from the equation and use the principles of quantum physics. As a result, no matter how powerful quantum computers are, they cannot crack QKD since there is no mathematical barrier to break in the first place.
QKD works by transmitting light particles through fiber optic cables. Using the properties of quantum mechanics, when disturbances such as eavesdropping are detected during transit, the key adapts and changes. As a result, attackers cannot hack the transmission, and an unauthorized party will not be able to snoop the network.
Why The World Needs QKD In Space
QKD is an enabler to unbreakable encryption. Getting it into space not only helps improve its performance but solves some of its current challenges. To understand further, here are some significant benefits of QKD in space:
Better Data Security
Many industries – including the government and its military – rely on satellite networks to transmit sensitive data. The traditional encryption method of sending scrambled messages and a key to decipher it uses a binary stream of 1s and 0s. Capable hackers can snoop these messages and use their computers to decode them – without the sending and receiving parties’ knowledge.
With QKD, these hackers can no longer eavesdrop or capture the data in transit. Quantum systems use qubits (quantum bits), which can change the key on the fly as soon as it detects any disturbance.
Better Infrastructure Setup
Unlike conventional cryptography, packet switching in QKD relies on the physical photon state instead of computation processes.
In purely terrestrial applications, there should be a fiber link between each endpoint for the key exchanges. It involves installing building-to-building equipment, which can be costly and risky.
Using satellites can help to minimize the cost and security risk dramatically. Plus, it also makes QKD networks more scalable. Establishing numerous communication links with a single satellite is better than having to build hundreds of fiber links.
Eliminates Risks Of Tampering
Fiber repeaters can help extend the distance traveled by photons. However, these repeaters are not immune to tampering – which defeats the purpose of having better data security.
QKD in space, through satellites, is a better option. It eliminates the use of fiber repeaters and thus the risk of tampering.
Challenges Facing QKD In Space
Getting QKD in space also has its drawbacks, which usually arise from its security relying on the physicality of the system. Fortunately, these drawbacks are not permanent, and advancements in technology will eventually overcome them.
Crude Light Bouncing
As of today, there are no satellites available to produce coherent photons that can carry information. Consequently, researchers have to rely on existing satellites to bounce the photons off – sort of like a boomerang effect.
With geodetics as the primary purpose of these satellites, it is understandable that their ability to bounce QKD photons has a degree of error.
Light Transmission Challenges
Cloud cover can affect QKD transmission. Furthermore, sending the light from the satellite down to Earth can also be an issue. The downlink lasers still need to get considerable fine-tuning to eliminate dispersion in a broad area.
QuantLR’s Space Mission And The Future Of QKD
QuantLR is at the forefront of QKD’s development and implementation. And as part of our mission to develop the world’s first and only secure, low-cost Quantum Cryptography solution, we’re heading into orbit.
This coming winter, we’re sending some of our QKD equipment to the International space station to secure networks between satellites and Earth.
“We are creating a new way to defend data,” says Shlomi Cohen, CEO of QuantLR.
One of our focuses at QuantLR is data in motion, and in the coming years, space will be the lead generator of data traffic.
There are several benefits of sending QKD into space, and thankfully the benefits work both ways. The satellites can help improve QKD performance, while QKD can help secure data transmitted to and from the satellites.
Quantum Cryptography Offers A Secure Path For Human Progress
Implementation of quantum cryptography can help mitigate the negative side of advancing technology, such as the rapid increase in cybersecurity threats and breaches.
With quantum cryptography securing our networks, even if quantum computers become as common as the servers running today’s most popular applications, QKD will help secure the world’s information.