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Secure Video Conferencing via Quantum Cryptography

Roland Piquepaille writes "If you use a webcam to talk with your mom, this tool is not for you. But if you're working for a company and that you have to routinely discuss about sensitive future projects or the possible acquisition of another company, you need more security, and this new video conferencing system based on quantum cryptography is a tool you need. According to this article from Nature, researchers from Toshiba have developed a system which can generate 100 quantum 'keys' every second, fast enough to protect every frame in a video exchange. This technology, which today is working over a distance of about 120 kilometers, could become commercially available within two years at an initial cost of $20,000. This overview contains more details and references."

5 of 163 comments (clear)

  1. Hey Roland, I'm violating your copyright! SUCK IT! by Anonymous Coward · · Score: 5, Interesting

    Secure Video Conferencing via Quantum Cryptography

    If you use a webcam to talk with your mom, this tool is not for you. But if you're working for a company and that you have to routinely discuss about sensitive future projects or the possible acquisition of another company, you need more security, and this new video conferencing system based on quantum cryptography is a tool you need. According to this article from Nature, researchers from Toshiba have developed a system which can generate 100 quantum 'keys' every second, fast enough to protect every frame in a video exchange. This technology, which today is working over a distance of about 120 kilometers, could become commercially available within two years at an initial cost of $20,000. Read more...

    Here is the introduction from Nature.

    Scientists from Toshiba's Cambridge Research Laboratory unveiled their invention to business leaders and government officials at Britain's Department of Trade and Industry in London on 27 April.

    Their system is capable of generating 100 quantum 'keys' every second. This is fast enough for every individual frame of video to be protected by its own encryption. "This makes the system highly secure," says Andrew Shields, who leads the Cambridge team. "It would take an enormous computational resource to crack this frame by frame."

    Of course, today's videoconferencing tools using conventional encryption are already pretty secure. But if the NSA wants to check your conversation, I betit can. With quantum cryptography, this is a different story.

    Quantum cryptography promises to stop such eavesdroppers. The system works by first establishing a 'key' that provides instructions on how to decode an incoming message. This key is built into the quantum state of photons. Intercepting a message breaks the key and alerts the sender and intended recipient to the security breach, because the very act of observing a quantum state changes it.

    The Quantum Information Group at Toshiba gives more details on this subject on this page about Security from Eavesdropping . Below is a diagram illustrating the concept (Credit: Toshiba's Cambridge Research Laboratory).

    Using single photons to carry the bit material for the key prevents undetected eavesdropping. Because each bit is carried by a single photon, it is not possible for a hacker to tap in and remove part of the signal, as shown in the illustration. Single photons do not split, so if the hacker (Eve) measures the photons on the fibre, they will not reach the intended recipient (Bob). Only the photons that arrive at Bob are used to form the key, so Eve cannot gain any useful information by this crude 'tapping' attack.

    The first commercial applications of quantum cryptography are now about one year old. However, this new system offers new levels of performances, according to Nature.

    Unlike previous systems, which become unreliable when they heat up, this device can run continuously for more than four weeks, says Shields. The quantum information can only go so far before being corrupted by random interactions with surrounding material, however. "We've shown this can work over 120 kilometres of fibre," says Shields.

    Toshiba has already built a Quantum Cryptography Prot

  2. Boycott Roland Piquepaille Stories by goldspider · · Score: 5, Insightful

    Yes, offtopic, I know. Moving on.

    There are a lot of us here who object to Roland Piquepaille's well-documented practice of using Slashdot to direct readers to his site and thereby generate ad revenue for himself.

    Roland Piquepaille contributes none of his own work (it's ALL derivative of others' efforts), and Slashdot is more than willing to sell their readers out to this character.

    So the next time a Roland Piquepaille-submitted story comes up, don't read it. Don't post replies. Don't even acknowledge that the story is there.

    It's time we send Slashdot the message that we don't like being taken advantage of in this manner.

    --
    "Ask not what your country can do for you." --John F. Kennedy
  3. Re:THE TRUTH ABOUT ROLAND PIQUEPAILLE by benjamin_pont · · Score: 5, Informative

    How does this kind of thing happen? Just curious.

    benjamin_pont's Recent Submissions

    Title
    Quantum leap in secure web video

    Datestamp
    Friday April 29, @02:09PM Rejected

  4. Why? by nacturation · · Score: 5, Insightful

    I don't see this as being really practical for security. So you've got all of this quantum-encrypted video which is infinitely better than an SSH-encrypted stream and you're feeling pretty smug about how unbreakable it is. Meanwhile, the janitor has planted a bug under your desk and is eavesdropping on everything you say. Or someone else hid a pinhole camera in a plant and is recording it all.

    While I applaud the research and find the technology cool, I don't think a lack of decent encryption technology is the weakest link with regards to security.

    --
    Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
  5. Let's use a buzzword! by Bender0x7D1 · · Score: 5, Informative

    There is nothing really exciting about this other than the overkill usage of quantum cryptography (also called quantum key exchange).

    Basically, they are trying to generate enough keys so any succesful breaking of the cipher used gets only one frame of video. The only "exciting" part is they are using quantum cryptography to do this. However, this is like using a sledgehammer to push in a thumb tack - It uses a lot more hardware, and isn't the easiest or best method.

    Another way to do this would be to conduct a large number of Diffie-Hellman key exchanges or STS exchanges, (one for each frame), and use the new key for each frame.
    Or, even easier, both sides could use identical Linear Feedback Shift Registers to generate the same keys that they need. They cost way less than $20k and since a compromise of the system at either end would destroy the privacy afforded by the quantum encryption, just as secure.
    Or, they could exchange one-time pads on a DVD and use the bits on there as the key. If my math is right, then a 4GB CD could hold enough keys for over 1100 hours of video, assuming a 256 bit key and 30 frames/sec. Exchanging 2 or 3 DVDs a year (if that) doesn't seem unreasonable.

    None of these methods require a dedicated fiber line connecting the two groups. It can be performed over regular Ethernet if the groups want to. Translation: I can use it to talk to someone more than 120km away.

    This isn't to say that some groups wouldn't want quantum security for something - if I was a Swiss bank that made daily transfers of a billion dollars to a German or Italian or French bank, then sure, I should spend the extra couple hundred k for an obscenely secure system.

    This also begs the question of why encrypt each frame differently? Since it is VIDEO, then something in the picture is probably important - like a PowerPoint slide or graph or something. Since a presenter usually spends a minute or two on each slide, this means that an attacker would only need to decrypt one out of every 1800 slides (assuming 30 frames/second) to get the information they wanted. I think that it is a good idea to change keys as often as possible, but you have to ask what is the benefit for the added cost/overhead. In this case, I don't think it is very much.

    So nice use of the "quantum cryptography" buzzword, but bad application of crypto technology in general.

    --
    Reading code is like reading the dictionary - you have to read half of it before you can go back and understand it.