Slashdot Mirror


Quantum Network Joins Four People Together For Encrypted Messaging (newscientist.com)

An anonymous reader shares a report: The quantum internet is starting small, but growing. Researchers have created a network that lets four users communicate simultaneously through channels secured by the laws of quantum physics, and they say it could easily be scaled up. Soren Wengerowsky at the University of Vienna and his colleagues devised a network that uses quantum key distribution (QKD) to keep messages secure [the link is paywalled]. The general principle of QKD is that two photons are entangled, meaning their quantum properties are linked. Further reading: Nature.

60 comments

  1. Will it still exist ... by Anonymous Coward · · Score: 0

    when noone is looking

    1. Re:Will it still exist ... by GoTeam · · Score: 1

      Does it change state when someone does look at it?

    2. Re:Will it still exist ... by vtcodger · · Score: 1

      Does it change state when someone does look at it?

      No, but it kills half the cats within 100 meters of any component of the network

      --
      You can't see ANYTHING from a car, You've got to get out of the goddamned contraption and walk...Edward Abbey
    3. Re: Will it still exist ... by Anonymous Coward · · Score: 0

      Sounds like an excellent feature to me.

    4. Re:Will it still exist ... by Anonymous Coward · · Score: 0

      Does it change state when someone does look at it?

      Is it the new Snapchat??

    5. Re:Will it still exist ... by Anonymous Coward · · Score: 0

      Yes. Just reverse: "+-+-+-+-+-+-" Simple.

  2. First received message.. by jimtheowl · · Score: 4, Funny

    Hello, I am Quantor Prince and have been stranded in entanglement after secret experiment from my captors. I have made causality agreement with guard who is willing to free and not free me for the sum ..

    1. Re:First received message.. by Anonymous Coward · · Score: 0

      I thought I saw your cat.

    2. Re:First received message.. by Anonymous Coward · · Score: 1

      Hello, I am Quantor Prince and have been stranded in entanglement after secret experiment from my captors. I have made causality agreement with guard who is willing to free and not free me for the sum ..

      Hey! I am willing to and not to pay your sum!

  3. Coincidence? by chrism238 · · Score: 2

    ARPAnet also started with just four nodes: https://www.scientificamerican...

    1. Re:Coincidence? by Anonymous Coward · · Score: 0

      And the similarities and extrapolations stop right the fuck there.

    2. Re:Coincidence? by Actually,+I+do+RTFA · · Score: 1

      Probably a coincidence. ARPAnet made a triangular ring, and then had one more node off that. That's enough to test routing, etc. (A connects to B,C; B connects to A,C; C connects to A,B,D). Therefore, they can make sure A->B doesn't get confused and go A->C->A (repeat) ->B and A->D can make the hops. So,. useful for testing.

      This quantum nodes were connected in a ring, all four nodes connected each of the three others. The limit seems to be based on the fact that they had 12 multiplexed channels. I notice that 12 connections (if unidirectional) is the number needed to connect all 4 nodes to each other. (2 connections -> 2 nodes, 6 connections -> 3 nodes, 12 connections -> 4 nodes)

      --
      Your ad here. Ask me how!
  4. Re:Government will not allow it by Anonymous Coward · · Score: 0

    Sure they would. You'd just put it on your ridiculously insecure phone or Intel ME chip anyway.

    Government : "You sure showed us, lol."

  5. High stakes better by Anonymous Coward · · Score: 0

    Hello, I have found SchrÃdinger's cat. Is he dead or is he alive? $50,000 to bet.

  6. What happened? by Anonymous Coward · · Score: 0

    Did you run out of bitcoin stories?
    Nobodys buying that crap anymore, dummy

    1. Re:What happened? by Anonymous Coward · · Score: 0

      Quantum is the new Global Warming. If you claim to be an urban sophisticate you have to believe it!

    2. Re:What happened? by jimtheowl · · Score: 1

      You do not have to be an 'urban sophisticate' to believe in the scientific method.

    3. Re:What happened? by Seven+Spirals · · Score: 1

      I'm not trolling I'm asking... How much physical evidence for quantum entanglement is there? I gotta admit that it does sound like bullshit, but then again I'm sure airplanes would sound like bullshit to the Romans. Wouldn't quantum entanglement also give you instant communications (before it gave super fast CPUs) by altering one entangled bit say in Los Angeles while someone else gets the signal in Cairo? I haven't seen anything to indicate that the idea works at all for any purpose. It's been talked about for years. Quantum Computing is sounding a lot like "Flying Cars" and "Better Batteries". I know both are possible, but I sure don't see evidence that it's gonna happen. Then again, I'm not a Quantum researcher.

    4. Re:What happened? by Anonymous Coward · · Score: 0

      I'm not trolling I'm asking... How much physical evidence for quantum entanglement is there? I gotta admit that it does sound like bullshit, but then again I'm sure airplanes would sound like bullshit to the Romans. Wouldn't quantum entanglement also give you instant communications (before it gave super fast CPUs) by altering one entangled bit say in Los Angeles while someone else gets the signal in Cairo?

      The memory controller in your computer makes certain guarantees about access to and availability of data. In order to do useful work it must protect against production of nonsensical outcomes in all situations.

      Quantum world works the same way at a very basic level ensuring only consistent outcomes are possible.

      In the same way applications are necessarily denied details (excluding meltdown, spectre...ad nausea) about inner workings of processors to maintain various guarantees the quantum world imposes similar (infallible?) limits on what can be known about the system.

      As an application or user of reality you would have to find a bug or loophole in computer or reality to gain forbidden knowledge about quantum interactions sufficient to become neo and locally propagate information FTL.

      In short there is no spoon. The only thing that exists at all is quantum interaction and they don't give one fuck about your quaint notions of locality and reality.

    5. Re:What happened? by Anonymous Coward · · Score: 0

      Altering a bit destroys its entanglement, so what you suggest does not work. If you change the bit in LA, the measurement in Cairo will not be affected.

  7. Be careful by nospam007 · · Score: 1

    You remember what happened, when Alexander Graham Bell added a third phone to his 'network'.
    He was relaxing in his bath when the phone rang. Wet like a dog he hobbled to the phone just do detect the first ever 'wrong number'.

  8. ..strange by kiviQr · · Score: 1

    It said I had a message. I opened it and it wasn't there!?

  9. I knew this because by Oswald+McWeany · · Score: 1

    I knew this because my quantum ai blockchain device from Elon Musk had already told me.

    --
    "That's the way to do it" - Punch
  10. Pointless use case by WaffleMonster · · Score: 1

    At the end of the day this is all still rooted in symmetric encryption. Given todays cost and capability of storage it's just as easy to pre-fill a lifetime supply of "messaging" or voice communications in an OTP pool as it would be to initially provision secret keys in quantum modem doodads to support quantum encryption.

    Only OTP pools are way cheaper and easier.

    Where quantum crypto would be useful is in securing high bandwidth (multi-gigabit) data links.

    1. Re:Pointless use case by Anonymous Coward · · Score: 0

      It is also very hard to figure out if the system is working as expected because you can't monitor it. You can only use the endpoints which appear to be normal.

    2. Re:Pointless use case by Anonymous Coward · · Score: 0

      Right. You could fill a 10-TB HDD with your OTP and physically give it to someone and be assured of secure communications with them effectively forever, but classical one-time pad exchange still has all of the same flaws that it's been known to have for the last eighty-odd years, namely the lack of transport security of the OTP itself and the difficulty of scaling to many people. QKD solves those problems.

    3. Re:Pointless use case by WaffleMonster · · Score: 1

      Right. You could fill a 10-TB HDD with your OTP and physically give it to someone and be assured of secure communications with them effectively forever,

      Honestly gigabytes would be more than enough for text and voice communication. 128 GB sd cards are like $20.

      but classical one-time pad exchange still has all of the same flaws that it's been known to have for the last eighty-odd years, namely the lack of transport security of the OTP itself

      No it's the same exact problem either way. Whether you are guarding OTP or an initial secret for quantum keying the total security of the system hinges upon that secret information in whatever form it happens to reside in being successfully guarded. Quantum in no way changes that.

      itself and the difficulty of scaling to many people.

      I don't understand the basis for such schemes being limited to quantum and all the relevant details are pay walled. There are numerous schemes that can be employed to enable via centrally trusted agents to facilitate communications amongst peers.

    4. Re:Pointless use case by Anonymous Coward · · Score: 0

      You don't really need a lifetime of OTP either.
      Preshared key data (like one key per connection and per megabyte transferred) would make a lifetime supply easier to prefill.
      Not like anyone will do this anyway.

    5. Re:Pointless use case by Anonymous Coward · · Score: 0

      Quantum encryption doesn't need any provisioning. The measurement basis can be sent unencrypted on a classical channel.

      Some sort of authentication on that classical channel is still a good idea to make sure that the encrypted connection isn't with a man-in-the-middle.

    6. Re:Pointless use case by Anonymous Coward · · Score: 0

      If the error rates are low enough, you know that the entangled photons are coming from the same party that sent the measurement basis over a separate classical channel, because any other scenario is too improbable.

      You don't know if they are the correct party, but I'm not clear how monitoring would help with that.

    7. Re:Pointless use case by WaffleMonster · · Score: 1

      Quantum encryption doesn't need any provisioning. The measurement basis can be sent unencrypted on a classical channel.

      Some sort of authentication on that classical channel is still a good idea to make sure that the encrypted connection isn't with a man-in-the-middle.

      I think I understand now:

      1. You don't need to provision.
      2. If you don't provision it won't be secure.
      3. Security is the whole point of quantum key distribution.

    8. Re:Pointless use case by Anonymous Coward · · Score: 0

      But the quantum key doesn't need a quantum secret. Both parties generate online
      an OTP, using a public classic channel, and a quantum one.

      The static test on the resulting bit sequence can be used to certify that no
      third party has intercepted the OTP.

    9. Re:Pointless use case by WaffleMonster · · Score: 1

      But the quantum key doesn't need a quantum secret. Both parties generate online an OTP, using a public classic channel, and a quantum one.

      The static test on the resulting bit sequence can be used to certify that no
      third party has intercepted the OTP.

      The point of quantum cryptography is to provide secure communications.

      There is no such thing as secure communications without a means of authenticating communicating peers. There can be no security if you don't know who you are talking to in the first place.

    10. Re:Pointless use case by Anonymous Coward · · Score: 0

      Seems more complicated.
      An 8TB disk of noise seems a bit cheaper than any quantum solution.
      Realistically you can even reuse the pad once or twice without any problem. At most someone snooping in on it will figure out what the pad was for a couple of packet headers that happened to align at the same place.
      If you are want to you can decide to loop the pad at a non-byte boundary or do some other bit shuffling to make it a bit harder to snoop into.

      That, or share more drives.
      If you are that paranoid the cost of the drives are fairly insignificant.
      In a position like that you aren't going to establish any connection with someone you haven't met up with in real life anyway since people on the internet never is who they claim to be.

  11. Re:Government will not allow it by jellomizer · · Score: 1

    Or perhaps they will, and our own paranoia will keep us in our place.
    Why bother putting the resources in spying on us when it is much easier to make us think that we are being spied on.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  12. Non-paywalled article source, please? by Rick+Schumann · · Score: 1

    Article is behind a paywalled and I can't find a non-paywalled source, thanks so much for that.

  13. "Joins Four People Together" by Anonymous Coward · · Score: 0

    Wasn't there a movie about this? But I thought it was only three people.

  14. Bullshit by sexconker · · Score: 1

    No one has ever been able to detail how entangling particles helps anything with regards to encryption or key sharing.

    If you pass out entangled particles to a set of people, all you gain is the ability to know the state of their particle as soon as you look at yours. (And you could have done that at the time you distributed the particles - there's no FTL transfer of information, and no breaking of causality.)

    If you are able to securely pass out entangled particles, you are able to securely pass out convention particles describing a conventional key.
    If you are not able to securely pass out entangled particles, you're not gonna do much, are you?

    1. Re:Bullshit by Anonymous Coward · · Score: 0


      If you are able to securely pass out entangled particles, you are able to securely pass out convention particles describing a conventional key.

      I don't think this is accurate. The question is always how do you KNOW that the particle wasn't intercepted somewhere along the line? With quantum key exchange, you know if your key was compromised along the path. If it was, don't use that key. With conventional key exchange, you have zero way of knowing if someone put a splitter in the line somewhere, and intercepted your key.

      So all that's possible with quantum key exchange is for the attacker to prevent you from exchanging keys, since the attacker can simply observe all particles.

      The real problem with quantum key exchange is distance. Longer distances require repeaters. And it's completely possible to intercept the key at the repeater without being detected. So now suddenly you've shifted your problem into having to protect ALL the repeaters down the line.

    2. Re:Bullshit by WaffleMonster · · Score: 1

      I don't think this is accurate. The question is always how do you KNOW that the particle wasn't intercepted somewhere along the line?

      Quantum doesn't tell you this in a vacuum. Only when combined with cryptographic operations involving guarded secrets can the integrity of the channel be established.

      With quantum key exchange, you know if your key was compromised along the path. If it was, don't use that key. With conventional key exchange, you have zero way of knowing if someone put a splitter in the line somewhere, and intercepted your key.

      No. There is nothing that can't be done using conventional cryptography that quantum brings to the table. Numerous keep agreement protocols based on symmetric keys exist which perform the exact same function with no known weaknesses.

      The only advantage of quantum are certain immunities from future compromise of cryptographic algorithms but even that isn't absolute.

      So all that's possible with quantum key exchange is for the attacker to prevent you from exchanging keys

      It can also reveal information about the nature of the guarded secrets used to authenticate the quantum channel.

    3. Re:Bullshit by WaffleMonster · · Score: 1

      If you pass out entangled particles to a set of people, all you gain is the ability to know the state of their particle as soon as you look at yours. (And you could have done that at the time you distributed the particles - there's no FTL transfer of information, and no breaking of causality.)

      If you are able to securely pass out entangled particles, you are able to securely pass out convention particles describing a conventional key.
      If you are not able to securely pass out entangled particles, you're not gonna do much, are you?

      The point of quantum crypto is disconnecting future keys from observable reality.

      Assume an adversary was able to record all communications and they kept them forever.

      With the information collected they may eventually find a way to derive initial encryption keys either by stealing, brute force or leveraging cryptographic weaknesses and in-turn use that information to help facilitate future breakage of key rotation/management schemes designed to reinforce initial encryption keys.

      What quantum crypto does is provably break the link between initial key and future keys so even if an adversary is recording everything and manage to break the initial key they are fundamentally denied the ability to break follow on keying by leveraging any data classically communicated based on previous knowledge of existing keys.

      The only advantage quantum provides vs. normal cryptography is it guards against unknown cryptographic weaknesses. In the absence of such weaknesses quantum crypto is totally worthless.

    4. Re:Bullshit by Anonymous Coward · · Score: 0

      The sender and receiver of the key each measure one half of an entangled pair. They randomly decide which conjugate bases to make their measurements, and randomize this choice for every photon. After measurements are done, they can share which basis each measurement was done in, and only use measurements where they both used the same basis. They can then check a random subset of the measurements to see if they follow the correct correlation. Any eavesdropped would necessarily ruin the correlation, because they would have to guess which basis to measure in, and will pick the opposite of the sender and receiver some of the time. One person measuring the wrong basis will wreck the entanglement and hence the correlation between measurements. This is a consequence of the no cloning theorem that prevents someone from copying a quantum state.

      In order for this to be hackable, the eaves dropper has to guess the same basis whenever the sender's and receiver's choices agree or near perfectly guess which set of bits the sender and receiver will use for a test comparison and not measure those photons.

      You can do a simpler version without the entanglement: Send photons with either linear or circular polarization as randomly chosen. If the sender chooses linear and sends a vertical polarization and an eaves dropped accidentally guesses circular, their circular measurement & re-transmitted circular polarized photon will cause the receiver to get a 50-50 mix of vertical and horizontal polarization. Unless the eavesdropped perfectly chooses linear vs circular for every photon in the test set (p ~ 1/2^n), the sender and receiver and figure out the eavesdropper is there using a public channel to share their basis choices after the photons were sent.

      Even if the sender and the receiver don't figure out the eaves dropper is there, any bit he guessed the wrong basis to measure is unknown to him. So he would on average only have half the bits in the key.

    5. Re:Bullshit by Anonymous Coward · · Score: 0

      Unlike all other uses for entanglement I know of, quantum encryption is actually legitimate.

      The important part about the entangled particles is that they can't be measured completely so they can't be copied. Because they are a pair, there is already a single copy and no more copies can ever be made by any means.

      Nothing prevents an attacker from getting the key shared using quantum encryption, but the difference is that the intended recipient knows something went wrong and can probably tell the sender before the key is used to send any actual data.

  15. Phrasing! by SuperKendall · · Score: 1

    Quantum Network Joins Four People Together

    That headline summary sounds like a bad SyFy reboot of The Fly.

    With Stan Winston gone I'm not sure it could be done properly.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
    1. Re:Phrasing! by Locke2005 · · Score: 1

      Quantum Human Centipede?

      --
      I've abandoned my search for truth; now I'm just looking for some useful delusions.
  16. Researchers have created a network ... by grep+-v+'.*'+* · · Score: 1

    Researchers have created a network ... and could easily be scaled up. ... devised a network that uses quantum key distribution (QKD) to keep messages secure [the link is paywalled].

    Lawyers created secure networks that decades ago. If you don't pay ("the link is paywalled") you can't see the message. Or if you DO see, you have to poke your eyes out. (You've seen those email trailers from some companies: intended for; if not then you are restricted from [breathing] ...)

    Besides, TERRORISTS, and "Here's a $5 wrench, go find out what he knows."

    --
    If the universe is someone's simulation -- does that mean the stars are just stuck pixels?
  17. paywall paywall paywall by Anonymous Coward · · Score: 0

    Next time you post a link to an article that's paywalled with no alternative source, we'll have a poll to see which body part of yours we get to remove.

    1. Re:paywall paywall paywall by Locke2005 · · Score: 1

      Obviously not the brain, pretty sure that's already gone missing!

      --
      I've abandoned my search for truth; now I'm just looking for some useful delusions.
  18. Quantum Secrets by mentil · · Score: 1

    The only way four people can keep a quantum secret is if three of them are dead, or a quantum superposition of alive and dead.
    The death certificates will say "Cause of death: wavefunction collapse."

    --
    Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
  19. So, um... by Locke2005 · · Score: 1

    What's the porn like on that network?

    --
    I've abandoned my search for truth; now I'm just looking for some useful delusions.
  20. Entanglement is resonance by Anonymous Coward · · Score: 0

    If they stopped their entanglement bullshit and looked at it properly, you'd see it's proof of resonance in matter. All of that crystal at any given time must be in a single state, i.e. resonant, so at any given time the photons ejects must be the same. So if you filter for time (which they always do), the photons will be the same.

    And lots of matter particles are resonant, so can lots of light 'photons' resonant and behaving like a single photon. in other words the photon isn't a single big particle, its lots of smaller resonant things. So they don't need to talk this bullshit to fix up their model, the fix is in the logic of their own experiment!... The light goes through BOTH slits, not just a 'probabilistic wave function'.

    It's not suitable for encryption, every nF spins later the state will be the same (depends on the structure).

    Entanglement as 'understood' currently:
    https://www.youtube.com/watch?v=8ORLN_KwAgs

    Entanglement as reality:
    1. All entanglement experiments filter for 'successful entanglement', in Quantum Eraser this is a 'Coincidence circuit', selecting photons that arrive at the same time. In the Delft's recent experiment it was an explicit filtering before the Bells threshold test.
    2. Selecting photons ejected by the beta barium borate (BBO) crystal at time T=0, selects a subset of photons with a particular polarization.
    3. All the matter in the BBO crystal must be in the same oscillating mode at T=0, that causes all photons to be ejected with a corresponding polarization.
    4. T =0 is arbitrary, the experiment does not force a time, so all of the matter across the crystal must in the same state at any given time.
    4. i.e. matter is resonant.
    5. Since the only known force in light is electric (and its magnetic relative), that resonance must be electric.
    6. Entanglement is proof of electric resonance in mass.

    Entanglement Mk II:
    You can extend the experiment to prove more:
    1. Every 1F spin, the matter should be in the same state.
    2. So if you can make an experiment that compares photons at T=0, against protons at T=1 spin, they will also be 'entangled'.
    3. You would probably find it easier to work with W, the wavelength, which should be approximately the size of a current model of the proton (p*r*oton). The photon at X=0, should be 'entangled' with the one at X=W and X=2W, and X=3W...

    Light rides electric resonance wave
    1. Matter is resonating the electric resonance wave by the previous Entanglement experiment.
    2. Light has an electric wave property.
    3. So light is also riding the electric resonance wave., since it has an electric oscillating field it cannot do otherwise.

    Experiments:
    Obviously to be resonant, we need the electric force to propagate at infinity (even if the effects propagate through matter spins at the speed of light). So that would be the real winner here: Can you devise an experiment that can detect the initial push of electric force propagates at infinity velocity?

    If the speed of matter and speed of light result from the dipolar oscillation over the resonance wave (with 0 and C being the lowest energy velocities, and C/2 being the maximum energy in velocity). Then *monopoles* are not limited to travel at C. (They wiggle, but this is the field from their wrapper). A discharged electron is a -ve monopole without its wrapper. Can you devise an experiment that measures the speed of these monopoles through a vacuum? Can you prove monopoles travel faster than light?

    ostulate A: Mass isn't real
    Postulate B: the energy in light is also 'kinetic'
    Postulate C: Light bind force must be cyclical
    Postulate D: only 2 fundamental particles are possible
    Postulate E: the only force is electric
    Postulate E2: The binding force (Postulate C) is electric
    POSTULATE F: The speed of light is obvious
    POSTULATE G: Time is measured in spins
    POSTULATE H: All dipoles are equal, matter,even red and blue light
    Postulate I1: Donut Particles
    Postulate I2: Donut Particles are themselves

  21. Quantum bullshittery by Anonymous Coward · · Score: 0

    I haven't posted V1 yet, but these properties you claim are independent are not independent.

    Spin I use as a proxy for time.
    Location, your magic uncertain jiggle, I can explain and even make a prediction about, giving testable experiments, and its the basis for my gravity.
    Polarization in V1 isn't a separate spin axis, it comes from velocity.

    So you're taking a bunch of connected things, from a resonant system, and pretending they're independent parameters, that only become connected when you measure them.

    It's total bullshit, once you see how it works, the penny drops and you cannot unsee it.

  22. Blind to the resonant field by Anonymous Coward · · Score: 0

    Look, the whole problem here with physics is its blind to the resonant field.

    You have an oscillating electric field. You cannot measure it because any device you put in the field orders itself to be resonant with it.

    A dipole is up-down, when the field under it is down-up. The matter of your equipment cancels the field it is trying to measure.

    So you have Quantum mechanics models, and these model the inner monopole (+ve or -ve) as if a proton is jiggling around tracing out a sphere, or an electron is tracing out a disc, or some other structure. And you cannot see the donut/anti-donut wrappers around it that is causing that jiggle!

    You're blind to large parts of matter, and blind to the underlying field.

    So you have all these magic 'jiggles' which you wrap in a phrase "Heisenbergs uncertainty principle" as a way of not examining them.

    These encryption 'jiggles' are not random, they are not suitable for encryption. They are obfuscation not encryption.

  23. Re:Government will not allow it by Anonymous Coward · · Score: 0

    Or perhaps they will, and our own paranoia will keep us in our place.
    Why bother putting the resources in spying on us when it is much easier to make us think that we are being spied on.

    Just like people think the US millitary has tech that is 50 years ahead of anything in the consumer market?

  24. Cat by Anonymous Coward · · Score: 0

    I opened the message and my cat died