Boffins receive quantum key from moving plane A group of German researchers has taken a step closer to achieving quantum key distribution with satellites, receiving quantum keys transmitted by a moving airplane. The experiment is described in this paper (PDF) presented to the QCrypt conference in Singapore last week. Led by Sebastian Nauerth at the Ludwig Maximilian …
Obviously the "too slow" label by the reporter was a stupid remark on his part. The real value of quantum cryptography is for military communication, not surfing the Internet. And for military communication, 120 bits per second is very useful. Present VLF data rates in the 3-300Hz band for submarine communication have data rates in this range. If it's a fast enough data rate to order the launching of nuclear ICBM's, it's not "too slow for a data channel".
And isn't the point that the data channel doesn't have to be THE communication you want to send? Set up an encryption key using the data channel, then broadcast encrypted data over the public airwaves if you like. Because there was no "sniffable" handshake and agreement on keys, data encrypted with that key is 100% secure.
All you need to do is transmit the KEYS so they can't be sniffed / interfered with. And making sure the keys are sufficiently large. 120 bits per second, call it twenty seconds to exchange keys (2400 bits), do that once a day and keep transmitting at GB/s using the agreed-upon key over more conventional channels.
if this is a *key* transfer and is completely secure then the *main* data channel can run as fast as necessary *provided* the key is big enough (and probably 1 time use).
The GPS data channel is 50 bits a second. It depends what you want to send and where you want to send it from if a data channel is fast enough. Sometimes you don't get to choose either (New Horizons will dump its 8GB data recorder contents over a sub 1kbs channel because it's outside the orbit of Pluto).
Well done on a 1st effort.
OR key distribution.
Secure key distribution is exceedingly difficult (impossible?) once a bird is in orbit. That means that rather a lot of satellites up there just forward transmissions like overpriced repeaters. I won't point out what type of mischief that would allow an attacker to get up to if he or she were to intercept unencrypted network traffic. If folks don't know what I am talking about, do they need to know?
Sorry guys. ELF transmissions, "Based on parameters supplied by the Navy, estimates have ranged from 1 bit per second to 1 bit per 10,000 seconds."
" This band is used to send short coded "phonetic letter spelled out" (PLSO) messages to deeply submerged submarines that are trailing long antenna wires."
http://www.globalsecurity.org/military/systems/ship/sub-comm.htm
The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2024
