Quantum Xchange & Quantum Key Distribution (QKD)...entangled photonic communications over long distances

Start watching this video, here: https://youtu.be/KnxLoScPCcQ, or here: https://quantumxc.com/watch-quantum-xchanges-tedx-talk/ at 5:39:45 to hear John Prisco, CEO of Quantum Xchange, discuss how QKD works, why we need it, and the general context of encryption.

I took away three key points:  1) the Chinese government has a 1,240 mile QKD link between Beijing and Shanghai, showing this can happen over land...over long distances, 2) they also have a satellite link that uses QKD, showing this can happen through space, and 3) Quantum Xchange has their link in the Holland Tunnel (and in fiber cables around the East Coast).  I read somewhere else that the US can now do this via an airplane and ground station, allowing for secure communications to aircraft.

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OK, so the video only covered points 1 and 2.  I learned the 3rd point today from a news article that @Quantum_Xchange tweeted.  Here is Quantum Xchange's website:  https://quantumxc.com/

So, how does it work?  We entangle photons (each is '1' or '0' and together those bits make up a quantum inspired algorithm key) and send them down the link.  If somebody tries to look at them, they lose their entanglement and change.  They show someone looked (tamper apparent).  It is like Schroedinger's Cat...if someone looks the wave function collapses, and quantum values collapse to classical ones.

Pretty cool stuff.  Photonics based networking.  Speed of light, slowed by repeaters and other equipment. 

I am still waiting for data teleportation and instantaneous communication of states between photons and electrons (if I do something here, it immediately determines the value there...and there could be very far away).   
Thank you for reading. 

​Jeffrey Cohen, May 30, 2019, Founder & CEO of Chicago Quantum, a division of US Advanced Computing Infrastructure, Inc.

Another update on June 6, 2019.  I just posted yesterday about British Telecom (BT) going live with their 125km QKD network in England in March 2019 on this website.  I tweeted on it @chicago_quantum. 

Looks like BT has been working on this since 1993 (when they sent their first quantum encrypted message).