There's a better article here (which is the source):<p><a href="https://www.toshiba.eu/pages/eu/Cambridge-Research-Laboratory/toshiba-announces-breakthrough-in-long-distance-quantum-communication" rel="nofollow">https://www.toshiba.eu/pages/eu/Cambridge-Research-Laborator...</a><p>Basically their achievement is that they have done quantum key distribution over a distance of 600km, which is apparently a world first. And I suppose it demonstrates commercial viability.<p>For people not familiar with the idea: They didn't send a genome over the quantum channel, they sent a private key over the quantum channel, and then encrypted the genome with that key using conventional encryption, and then sent that encrypted genome over a conventional network.<p>Without QKD this process would have been done using public key encryption, which means the sender would have to have received the public key from a trusted source, usually you trust that source because a third source trusts it, etc, this is called the chain of trust. You can see how if a malicious party injects itself into the chain of trust the confidentiality is broken. With QKD you only have to trust that the person you want to talk to is on the other side of the quantum link you've established, i.e. the security is put firmly in the physical realm. Because of the quantum entangling properties of this link, a malicious party can't inject itself physically in the middle of this link, and can not eaves drop or manipulate it.
Can someone explain how this is a breakthrough compared to China's satellite system which achieved QKD in 2016? They also claim "ground-based QKD to beyond 500 km using a new technology called twin-field QKD"<p><a href="https://scitechdaily.com/china-builds-the-worlds-first-integrated-quantum-communication-network/" rel="nofollow">https://scitechdaily.com/china-builds-the-worlds-first-integ...</a>
We need a down to earth real guide on quantum, because many are convinced that superposition and entanglement are somehow communication and/or trust mechanisms. In reality entanglement simply means that one particle spins the opposite of another particle it's entangled with. They could already have been this way from entanglement, but we don't know it's actual state until observation (with scientific instruments small enough to read the spin of a particle, not eyes).<p>I'm probably completely wrong too.
> The company says a research team has used quantum cryptography to securely send and store human genome data<p>Unless I'm wrong, it appears to be a "milestone" in that they sent human genome data rather some other kind of data (I'm not sure how that is significant) and no new quantum cryptography breakthrough has been achieved?
Even if quantum crypto reaches distances of 100‘000km it would still not mean we can use it at home I suppose, because just having one switch/router between Alice and Bob would break the scheme, no?