It's not quite a quantum internet — yet. But researchers at Los Alamos National Laboratory in New Mexico have developed a new, ultra-secure computer network that is capable of transmitting data that has been encrypted by quantum physics, including video files. The network, which currently consists of a main server and three client machines, has been running continuously in Los Alamos for the past two and a half years, the researchers reported in a paper released earlier this month. During that time, they have also successfully tested sending critical information used by power companies on the status of the electrical grid. Eventually they hope to use it to test offline quantum communication capabilities on smartphones and tablets.
"prevent a hacking attack on the electrical grid."
"There's a need for secure communications to prevent a hacking attack on the electrical grid," said Richard Hughes, a fellow at Los Alamos National Laboratory who is involved in the experiment. "At the same time, there are very demanding requirements for low latency. You can't have the normal time delays introduced by traditional cryptography." But Los Alamos researchers were able to satisfy the grid's low latency requirement — that is, the need for ultrafast, near real-time communications — as well as improve security, by developing a new type of quantum network. Previously, other types of quantum test networks have required that secure connections, or "trust," be established between every single machine on the network for every type of communication sent, slowing down the rate of transmission.
But in the Los Alamos quantum communications network, the central server acts the primary trusted authority, and handles all of the cryptographic key management functions, everything from quantum key distribution (that means sending two machines the keys necessary to establish a secure communications channel between them), to electronic signatures and certificates, which allow the communications to be sent and received.
The entire field of quantum cryptography, first proposed in the 1970s, relies on transmitting data in short bursts of light, using quantum physics to encode it, creating a communications channel so secure that the participants will know instantly if it has been cracked. "We've sent encrypted video with a key that rolls over every second, so even if someone broke an encryption key, it's only valid for a few seconds." Hughes told The Verge. The system relies on specialized equipment right now, including smart cards developed at Los Alamos over the past 18 years, and a custom server, but Hughes said researchers were hopeful that they could integrate the technology into consumer devices in the near future.