Russia and China successfully test quantum communication over satellite — 3,800-kilometer test explores possible encrypted networks for BRICS countries

A render of Mozi, China's quantum satellite used in this test.
A render of Mozi, China's quantum satellite used in this test. (Image credit: Chinese Academy of Science)

Following recent demos of quantum communication using undersea fiber optics, scientists from Russia and China have successfully demonstrated quantum communication over satellite, using China's quantum satellite (dubbed "Mozi"), as the two countries lay the groundwork for advanced encrypted communication networks that are safe from prying Western eyes — possibly for BRICS-aligned countries. The test was conducted using the satellite from a ground station close to Moscow, Russia, to another station based near Urumqi, China, over 3,800 kilometers, according to the South China Morning Post.

The satellite used to achieve this quantum communication, Mozi (also called Micius), has been in orbit since 2016 and is managed primarily by the Chinese Academy of Science. The collaboration with Russian scientists started in 2020. Then, in March 2023, a full quantum communication experiment was conducted between two ground stations, using encryption keys from Mozi to distribute two coded messages.

The coded messages used in the March 2023 test were fairly innocuous, before you get too excited— just a quote from Chinese philosopher Mozi and an equation from Soviet physicist Lev Landau. The more recent "full cycle" quantum communication test on December 14th, 2023, also used a few (presumably harmless) quantum key-encoded images.

For those unfamiliar, "quantum communication" refers to communication using "qubits". Qubits, like traditional "bits," can contain binary information. However, qubits are also incredibly fragile to outside interference, which means that it's very easy for a quantum computer to tell if qubits have been intercepted or interfered with in some way. 

Quantum communications are — in theory, at least — the most secure possible form of data transmission, exploiting quantum mechanics to be unbreakable without detection. The main drawbacks are the limited adoption/evolution of quantum computing and fundamental range weaknesses in current qubit transmission technologies— reportedly about 1,000 kilometers due to photon loss over long-distance wiring. 

While we can freely send regular old bits or bytes worldwide, it's much harder to do that with more fragile qubits since they're generally more prone to degradation. Advancements like this (satellites boost the effective range by as much as 3,800 kilometers) may start pushing us closer to a future of quantum communication networks, though, since international ranges are now clearly within the range of possibility. 

However, the communication test was ultimately just two regular old static images. How well quantum communication may fare in real-time video calling isn't currently known. However, a 2017 voice calling test was done between China and Austria, which could make high-bandwidth quantum communication feasible one day.

While quantum communications finally being achievable over undersea fiber optics and satellite communications is impressive, it isn't likely to become a dominant form of communication for any consumer, business, or state for quite some time. The rapidly approaching future of quantum computing may still be full of surprises, though, so who knows?

Alexey Fedorov of Russia's National University of Science and Technology and the Russian Quantum Center states, "Quantum communication networks could have many uses, but for now, quantum systems would ideally be suited to scientific research." 

While the technology is developing, it still seems there will be some time before it's used on a large scale for any real purpose. But Fedorov did speak of interest in quantum computing from the Russian finance sector and even alluded to the possibility of a quantum communication network between BRICS nations (Brazil, Russia, India, China, and South Africa) in the future.

Christopher Harper
Contributing Writer

Christopher Harper has been a successful freelance tech writer specializing in PC hardware and gaming since 2015, and ghostwrote for various B2B clients in High School before that. Outside of work, Christopher is best known to friends and rivals as an active competitive player in various eSports (particularly fighting games and arena shooters) and a purveyor of music ranging from Jimi Hendrix to Killer Mike to the Sonic Adventure 2 soundtrack.

  • hotaru251
    "Quantum communication networks could have many uses, but for now, quantum systems would ideally be suited to scientific research."

    ideally the world would be at peace but we all know the world doesnt follow the ideal route ;/
    Reply
  • bit_user
    For those unfamiliar, "quantum communication" refers to communication using "qubits". Qubits, like traditional "bits," can contain binary information. However, qubits are also incredibly fragile to outside interference, which means that it's very easy for a quantum computer to tell if qubits have been intercepted or interfered with in some way.
    From what I've read, the qubits are just used to send the encryption key. The error rate is still too high for the actual data to be sent via qubits.
    Reply
  • bit_user
    hotaru251 said:
    ideally the world would be at peace but we all know the world doesnt follow the ideal route ;/
    As we live in a world of finite resources, there will always be conflict. Nature has shown this, time and again.

    When you also account for the effects of human ambition, it's a wonder there aren't even more conflicts than what we currently see.
    Reply
  • COLGeek
    Lets stay on topic folks. Thanks.
    Reply
  • usertests
    https://en.wikipedia.org/wiki/Quantum_key_distribution
    Is their plan to use one-time pads, AES, or what?
    Reply
  • edzieba
    bit_user said:
    From what I've read, the qubits are just used to send the encryption key. The error rate is still too high for the actual data to be sent via qubits.
    Not so much the error rate but the data rate (though error rate is one factor affecting the data rate). But even if data rate were arbitrary, there would still be little reason to use it as the communication channel.

    'Quantum Encryption' is not encryption itself, it is a key distribution method that can be proven not to have been intercepted in transit. That's it. Sending plaintext bits over the entangled channel us utterly worthless, as all that would mean is you would be able to prove that somebody has or has not read your plaintext message (which by then is too late, because they've already read it). The goal is to send the key via the entangled channel, confirm it was not intercepted (discard it if it was), then use that provably un-intercepted key to then encrypt data that is classically encrypted and sent over a classical channel. If you have enough key bits then you can use a one-time-pad and have mathematically unbreakable encryption, otherwise you use a really big key and classical quantum-computation-resistant (quantum computation and quantum key distribution are effectively unrelated other than having 'quantum' in the name) classical encryption to make decryption particularly difficult if the ciphertext is intercepted.

    For this particular article: China has been demonstrating quantum key distribution via satellite for several years, this new development is just shipping an endpoint to Russia.
    Reply
  • ex_bubblehead
    As said earlier, stay on topic. The off topic material has been removed. Next comes the posters.
    Reply
  • COLGeek
    This thread has come to a close. Thank you to those who stayed on topic.
    Reply