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Scientists Race To Establish the First Links of a 'Quantum Internet'

Unknown Lamer posted about a year and a half ago | from the violate-causality-for-fun-and-profit dept.

China 82

ananyo writes "Two teams of researchers — once rivals, now collaborators — are racing to use the powers of subatomic physics to create a super-secure global communication network. The teams — one led by Jian-Wei Pan at the University of Science and Technology of China, the other by his former PhD supervisor Anton Zeilinger of the University of Vienna — have spent the last 7 years beating each other's distance records for long-distance quantum-teleportation. They now plan to create the first intercontinental quantum-secured network, connecting Asia to Europe by satellite."

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82 comments

No US (0)

Anonymous Coward | about a year and a half ago | (#42194139)

The word "US" is nowhere in sight.. Asia and Europe.. Why am I not surprised?

Re:No US (2)

liquidpele (663430) | about a year and a half ago | (#42194347)

Probably because quantum entanglement can't actually transmit information so it's not actually of any use besides "look, we entangled them further!"

http://en.wikipedia.org/wiki/Quantum_entanglement [wikipedia.org]

Thus, there is a correlation between the results of measurements performed on entangled pairs, and this correlation is observed even though the entangled pair may have been separated by arbitrarily large distances.[8] However, quantum entanglement does not enable matter to convey genuine information beyond the relativistic speed limit of normal spacetime.[9]

Re:No US (3, Insightful)

Anonymous Coward | about a year and a half ago | (#42194553)

You and a friend put one black and one white marble in a tin and shake. Without looking you each grab a marble and put it in your pocket. You travel some distance apart and then check your pocket. If your marble is white you now instantly know your friends marble is black. That's basically the level of communication in quantum entanglement.

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42194775)

Does quantum entanglement gain you anything over simply doing this marble experiment?

Re:No US (5, Informative)

Anonymous Coward | about a year and a half ago | (#42194865)

Someone else looking at the marbles breaks the entanglement in the quantum case, and you can't copy it before looking. If you tell your friend you got the white marble, and they see a white marble too, they know someone has been at their marbles. Then they know the key is not safe to use. The actual exchange is a little more complicated so you can't work out the key from the classical communication, only the researchers can tell if it has been seen or not. Classically, if you wanted to stop someone from seeing your marbles, I would recommend pants.

Re:No US (2)

lennier (44736) | about a year and a half ago | (#42196367)

If you tell your friend you got the white marble, and they see a white marble too, they know someone has been at their marbles.

So if your encryption key is compromised, you lose your marbles?

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42196439)

Classically I think youve lost your marbles

Re:No US (1)

History's Coming To (1059484) | about a year and a half ago | (#42195215)

However, this experiment is no different to having a black or white marble in your pocket and then looking at it to find out which you have. Knowing which your friend has does not supply any extra information, as to tell this person you are still limited by the speed of light. If you're a light year apart and you know what your friend has the information will still take a year to reach them, and the no-information-travels-faster-than-c rule is preserved.

Re:No US (1)

Runaway1956 (1322357) | about a year and a half ago | (#42195577)

Quantum physics is pretty far over my head - and yours too.

Your friend doesn't need you to tell him which color marble he has. He has the other half of the quantum linked marble pair! What you know, he knows, and vicey-versey.

Now, the real question is, how do we use those marbles to communicate in real time? Can we make them dance and vibrate synchronously? One marble. Or, more accurately, one marble here, one marble there. Maybe we can cause them to switch from black to white and back again, in some manner? There we have it - binary!

Now, there's just the pesky little problem of getting the marbles to cooperate, right?

Re:No US (1)

Anonymous Coward | about a year and a half ago | (#42196165)

how do we use those marbles to communicate in real time?...Now, there's just the pesky little problem of getting the marbles to cooperate, right?

Therein lies the rub. It would be great if we find a way to do that, but it wouldn't be with quantum entanglement unless something is fundamentally incorrect about quantum mechanics.

Re:No US (1)

History's Coming To (1059484) | about a year and a half ago | (#42198569)

Not at all - when you look at your marble you find out what colour you have, and can deduce the colour your friend has, but your friend receives absolutely no information from this, you have to send the message by traditional lightspeed means if you want him to know. He could, of course, just look at his and then you would both know what colour you have, but this isn't a "carrier wave" you can transmit information with.

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42197419)

Using this analogy a bit further, and knowing that you can't pick a specific marble to look at on purpose, but that the probability of each is 50/50. Say you want to send a black marble a long distance to represent a binary off.

Is there any benefit to the fact that you can get a bunch of tins of marbles, going first, you take a random marble out until you get white, then send your friend off with the that tin knowing he will get black. Then it is obviously not "quantum teleportation", or "action at a distance" anymore, but does it have any use in maybe cryptography, or preventing message tampering? Someone could replace

This is probably only as good as using voltage for messages right?

Re:No US (2, Insightful)

Anonymous Coward | about a year and a half ago | (#42194627)

Probably because quantum entanglement can't actually transmit information

You should re-read that. Quantum entanglement cannot be used for faster than light communication, but that doesn't mean there are not applications in transmitting information slower than speed of light. There definitely are some potential applications in that case, and it is more of a matter if it can be done practically.

Re:No US (1)

liquidpele (663430) | about a year and a half ago | (#42195081)

Ah, that's what I meant to type, whoops :/

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42196271)

I don't understand all the mathematics behind Quantum entanglement, but I do get the concept *I think*. Isn't saying that Quantum entanglement cannot be used for faster than light communication sort of misleading?

Say you had a space-ship capable of traveling at 20% the speed of light and it is going out on a 10 year mission. Couldn't you load up a big ole box of particles that are entangled with a matching box at the comm site on Earth? Maybe a bunch of boxes for redundancy? Given the right equipment, wouldn't instantaneous communication (text, voice, even video) be possible?

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42197407)

Nothing you could do to particles at one location could be used for communication without some sort of classical communication. Yes, when measuring something on Earth in several typical binary state examples, the spaceship will always measure the opposite, and there are some things that can be done on Earth to change what happens that differentiates this from the classical two-marbles-in-a-box mentioned above. But you don't get to chose which of the two states you get in the end. So if Earth does nothing, the spaceship will measure particles and see a 50-50 split between to states in such an example, and if Earth does something, the spaceship will still see a 50-50 split in states. Either way, it looks the same to people on the spaceship, it is only after a classical communication is established between the ship and Earth that they can see there was a correlation of states between the two points, but no patter at any single point. It is not like you can set one end to the "0" state and know the other end gets a "1", because forcing it into a particular state destroys the entanglement instead.

Re:No US (2)

sribe (304414) | about a year and a half ago | (#42194375)

The word "US" is nowhere in sight.. Asia and Europe.. Why am I not surprised?

Because we have always been at war with Eurasia.

Re:No US (1)

Impy the Impiuos Imp (442658) | about a year and a half ago | (#42194403)

You are upset the US merely invents half the shit invented each year, and the rest of the world the other half, and this falls in the other half?

Re:No US (3, Funny)

Kartu (1490911) | about a year and a half ago | (#42194959)

Pardon my ignorance, but are you implying that "patents half the shit patented each year" and "invents half the shit invented each year" are the same thing?

Re:No US (5, Funny)

denis-The-menace (471988) | about a year and a half ago | (#42194421)

Because Quantum Entanglement is not in the bible.

Re:No US (0)

Anonymous Coward | about a year and a half ago | (#42194931)

Because Quantum Entanglement is not in the bible.

uh... obviously, you haven't looked, in which case you should have known your statement is false. There is a 50% chance it's in there so long as you never look. But anyone that's actually looked knows there's plenty of tales of spooky action at a distance in The Bible.

Re:No US (1)

drkim (1559875) | about a year and a half ago | (#42195249)

Because Quantum Entanglement is not in the bible.

"...and god said, 'Let there be photons. And there were photons.'"

Let the be light (3, Funny)

MCRocker (461060) | about a year and a half ago | (#42198743)

Because Quantum Entanglement is not in the bible.

"...and god said, 'Let there be photons. And there were photons.'"

“In the beginning, there was nothing. Then God said, 'Let there be light'... and there was still nothing but, you could see it." :: Groucho Marx

Sounds cool! (0)

Anonymous Coward | about a year and a half ago | (#42194199)

I can't wait till it becomes mainstream!

Why the satellite? (1)

Hentes (2461350) | about a year and a half ago | (#42194237)

Couldn't quantum teleportation (paralell with some form of classical communication like the internet) be used as an uneavesdroppable communication channel?

Re:Why the satellite? (0)

Anonymous Coward | about a year and a half ago | (#42194357)

Sure everything could be used for everything, but why you so questioning?

Re:Why the satellite? (1)

19thNervousBreakdown (768619) | about a year and a half ago | (#42194407)

So I can use the concept of past tense as a flying car? Sweet!

Re:Why the satellite? (1)

hackula (2596247) | about a year and a half ago | (#42195211)

Clearly you have never seen Back To The Future...

Re:Why the satellite? (1)

Anonymous Coward | about a year and a half ago | (#42194387)

The article goes into details about actually teleporting photons to the satelite... the Summary is Deceptive

Re:Why the satellite? (0)

enemabagjones (2788805) | about a year and a half ago | (#42194439)

Probably because "quantum internet" is just a cover story for putting nuclear weapons into orbit.

Re:Why the satellite? (0)

Anonymous Coward | about a year and a half ago | (#42194495)

Looks like it is line of sight for now as they are using a laser.

Re:Why the satellite? (0)

Anonymous Coward | about a year and a half ago | (#42194707)

Quantum teleportation still requires the exchanging of entangled particles for every bit of information you want to communicate... which is pretty much what quantum encryption is already does anyway.

Re:Why the satellite? (5, Informative)

slew (2918) | about a year and a half ago | (#42195057)

Actually, in a practical system, quantum teleportation would generally be used to exchange an entangled photon from which a key can be extracted, the data would sent later using a classical communication technique (like the internet) using classical symmetric encryption scheme (say, like AES-CBC). Of course if the message is small enough, you might just transport the message entangled (instead of just a way to key the encrypted message), but that's much less efficient using current QM entanglement techniques***.

Today key exchange is often done with public-private keys, but the mathematical techniques behind them rely on "trap-door" functions (functions that are relatively easy to compute, but much harder to invert). Hard != impossible, so something that is merely hard to invert today, might be easy in the future. With a quantum key exchange scheme you don't transmit the key, only an entangled photon. Thus can't invert it (with currently known physics), and you can't even intercept it (w/o being detected), so it's impossible to deduce the key even in the future. Of course you could always resort to older time-tested techniques like this [xkcd.com] ...

The reason they need the satellite is to transmit the entangled photon (which is used to extract the key). A classical communications channel is effectively a cascade of store-and-forward (every amplifier and digital buffer along the way) so that every stage is making an "observation" and collpasing the quantum state. You basically want to convey the exact same photon you entangled so that the other side can receive it w/o the communication channel observing it in transit. Ideally, you'd bounce a batch of entangled photon off a satellite and the receiver gets the same photons you sent on the other side. Then both sides extract a key from their respective batch of entangled photons and use that key to exchange the message.

Of course, in a fancier system you might use that one entangled photon to quantum teleport some entangled qubits, but that would be more complicated.

***With current QM techniques, you don't really encode a pre-chosen key by somehow "entangling" it into a photon, you are basically creating a type of mind-meld (entanglement) of two photons in a way so that a quantum measurement made on one correlate with the other. With this, magically each side can extract the same information from their respective entangled photons meaning the same bit of information emerges from these measurements. That is why if someone intercepts the photon and retransmit it, both sides would know because they are unlikely have extracted the same bits from the measurments because with currently known physics it's not possible to observe and exactly recreate a quantum state (although apparently you can teleport it). If that doesn't make sense, it's because QM is not supposed to make sense, it just is (or maybe I'm not explaining it very well).

Re:Why the satellite? (1)

mpeskett (1221084) | about a year and a half ago | (#42224523)

If that doesn't make sense, it's because QM is not supposed to make sense, it just is (or maybe I'm not explaining it very well).

When we think reality is confusing, that's a fact about us rather than about reality - QM (or whatever the actually true laws of physics turn out to be) got here first, has always been in force, and has created that "normal" looking world we're all so used to. A severely curtailed approximate model was good enough to locate ripe fruit and throw rocks at each other, so that's what we find intuitive, but we're the weird ones - imagining the universe operating on the basis of tiny little billiard balls bopping about when that's not even close.

Put briefly: Quantum mechanics isn't weird, you're weird.

Re:Why the satellite? (1)

tehcyder (746570) | about a year and a half ago | (#42202613)

Couldn't quantum teleportation (paralell with some form of classical communication like the internet) be used as an uneavesdroppable communication channel?

Yes. Or no.

I'm quite the quantum guru today.

For the love of god. (0)

Anonymous Coward | about a year and a half ago | (#42194279)

Do not, under any circumstance, let any major ISP help with this.

speed (0)

Anonymous Coward | about a year and a half ago | (#42194397)

but will it lower my ping in starcraft?

Re:speed (1)

hackula (2596247) | about a year and a half ago | (#42195237)

"Quantum Entanglement" will be a new ability for infestors in Heart of the Swarm. Now Zerg can be imba at faster than the speed of light.

evesdropping (4, Insightful)

schneidafunk (795759) | about a year and a half ago | (#42194477)

Does evesdropping on a quantum message destroy the message? People talk about super secure quantum messages because it leaves a detectable trace, but does it also destroy the message in the process?

Re:evesdropping (5, Informative)

JesseMcDonald (536341) | about a year and a half ago | (#42194647)

Does evesdropping on a quantum message destroy the message?

Not exactly. The eavesdropping is actually detected during the key exchange (the "quantum" part), so if eavesdropping is detected, the message is never sent in the first place. If the key is exchanged without any eavesdropping, the message is encrypted with a one-time pad and sent through more traditional channels.

One-time pads are not vulnerable to cryptoanalysis—not even brute-force searches, as there is a valid key for every possible message (up to the observed message size), and no way to tell which one is the right one. The problem with one-time pads has always been key exchange, since you need a new, never-before-used bit of shared key for every bit of message. Quantum mechanics provides a way to generate shared keys for one-time pads without the risk of anyone eavesdropping (undetectably) on the key exchange.

Re:evesdropping (0)

Anonymous Coward | about a year and a half ago | (#42195335)

> The eavesdropping is actually detected during the key exchange (the "quantum" part), so if eavesdropping is detected, the message is never sent in the first place.

I misread this several times like this:

> The eavesdropping is actually detected during the transmission, so if eavesdropping is detected, the message was never sent in the first place.

That's time machine level sh*t, my brain was starting to short-circuit trying to understand how this could work.

Re:evesdropping (3, Informative)

The Raven (30575) | about a year and a half ago | (#42195691)

This is not quite true. True one-time pads are not able to be brute forced, but the pad must be as long as the message (10MB file = 10MB key). This is not how quantum key exchange is expected to work. The quantum key will be measured in KB, to encrypt a secure session or file measured in MB or GB. This means that it is damn secure, but could be brute forced given enough time.

The bit rate on these quantum links is not high enough for it to be practical to exchange pads the size of the file.

your point being? (0)

Anonymous Coward | about a year and a half ago | (#42195987)

"but the pad must be as long as the message" hence the "one-time" part.

Re:evesdropping (1)

Archangel Michael (180766) | about a year and a half ago | (#42196183)

I always thought that using a one time pad could use something like a simplified key. Take a irrational number like Pi, and then use an offset and size (length) for the pad instead of the whole key.

Pi offset 5,340,590,934,232,301 Length 2^19

Of course, it may be just that kind of setup is just as easy to crack as double ROT 13.

Re:eavesdropping (2)

JesseMcDonald (536341) | about a year and a half ago | (#42196797)

I always thought that using a one time pad could use something like a simplified key. Take a irrational number like Pi, and then use an offset and size (length) for the pad instead of the whole key.

The critical part of a one-time pad is that each bit of the key is truly random: there is one bit of entropy for each bit in the key. Anything less amounts to reusing bits from the key, so it's no longer "one-time". What you've described is essentially a form of pseudo-random number generator, with the offset into Pi as the seed. A PRNG can form the core of a symmetric encryption algorithm—just XOR the pseudo-random bit-stream with the message—but it isn't a one-time pad because the entropy of the PRNG output is limited by the entropy of the seed.

For example, the offset in your example would only require a brute-force search through an approximately 56-bit key space (the first 2^56 digits of Pi). If the message is much longer than 56 bits, and not random, then a brute-force search is likely to be able to distinguish the correctly decrypted plaintext from random noise. If there are patterns in the PRNG output it may be possible to take shortcuts and reduce the search time. A true one-time pad has a key for every possible combination of plaintext and ciphertext, so a brute-force search cannot tell you which key was used, or which message was actually sent, and there are no patterns for cryptoanalysis to take advantage of.

Re:evesdropping (1)

JesseMcDonald (536341) | about a year and a half ago | (#42196285)

Quantum cryptography in the popular "provably unbreakable by physical law" sense is indeed a one-time pad, and requires the secure distribution of a random key bit for every bit of the message. As you pointed out, however, the bit-rate of QKD is limited, at least for now. If you need to send a lot of data, and you're willing to settle for an algorithm subject to brute-force searches and other forms of cryptoanalysis, possibly including quantum algorithms, you can use QKD to derive an (arbitrarily large) shared key for a more traditional symmetric encryption protocol, and use that instead of a one-time pad.

Re:evesdropping (1)

WaffleMonster (969671) | about a year and a half ago | (#42199457)

Not exactly. The eavesdropping is actually detected during the key exchange (the "quantum" part), so if eavesdropping is detected, the message is never sent in the first place. If the key is exchanged without any eavesdropping, the message is encrypted with a one-time pad and sent through more traditional channels.

The details of the key exchange part is what is most interesting.. it can't be a fully quantum process since there is no possibility of binding identity to the quantum channel.

Verification of identity requires classical communication and standard encryption technology to verify an OTP peer.

An attacker pretending to be copious noise can still probe your initial key. If the key is later compromised an attacker could leverage the verifier during key exchange to obtain clues about subsequent OTP data transmitted via quantum channel.

Re:eavesdropping (1)

JesseMcDonald (536341) | about a year and a half ago | (#42206955)

You raise a good point. QKD ensures that you share the key with exactly one peer; it doesn't say anything about who that peer is. If, rather than simply eavesdropping, someone managed to redirect the channel to their own equipment, you could end up sharing the key with the attacker rather than the intended recipient.

For this reason, all QKD protocols require an authentic (but public) classical communication channel in addition to the eavesdropping-evident quantum channel. Once the peer has been authenticated, QKD can be used to arrange a shared authentication key for the next exchange. The first exchange, however, must be authenticated through more traditional means.

Yay for China (1)

Anonymous Coward | about a year and a half ago | (#42194481)

Now the rest of the world can proceed to steal their technology and not pay them for it.

Mah book writings ! (1)

bigattichouse (527527) | about a year and a half ago | (#42194571)

Yay! QE is a major component of my scifi book's communications. Yes, it's a crappy book, but it is my crappy book... and you can read it online without DRM, blah blah blah.

http://cruft-private-janitorial.com/?chapter=1 [cruft-priv...torial.com]

Can't wait for animated breakfast bar wrappers! Or Capt. Skyking brand Starling!

Re:Mah book writings ! (1)

bigattichouse (527527) | about a year and a half ago | (#42194613)

My thought was timed reading... where you only read the next qubit at predefined intervals to check for state.. and what is definitely a gross misunderstanding of QE (but useful as narrativium) - writing a state to the next particle. so particles are read-write in order, and they slowly "tick away"... but the base set are linked into the network.. so you can buy any random batch of particles and they link back to some other endpoint.

Re:Mah book writings ! (1)

mcgrew (92797) | about a year and a half ago | (#42196121)

Why not post it as a series of slashdot journal entries? [slashdot.org] Probably not a lot of slashdotters who don't like science fiction!

Offer it to bittorrent or Pr0n sites (1)

digitalamish (449285) | about a year and a half ago | (#42194661)

I promise you they will have it working in a week.

How much bullshit in one summary? (-1)

Anonymous Coward | about a year and a half ago | (#42194685)

Quantum internet ... quantum-teleportation .... intercontinental quantum-secured network.

I remember when scientists used to visit this site.

Re:How much bullshit in one summary? (0)

Anonymous Coward | about a year and a half ago | (#42194817)

I remember when scientists used to visit this site.

We still do.

I remember a time when people didn't dismiss actual research as BS because they made sure to they knew what they were reading about first. Actually, no, I don't... the internet has always had a decent sized chunk of people who jump at the chance to call something BS they don't like and then frequently support some BS they do like with equal lack of scrutiny or actual examination.

First (-1)

Anonymous Coward | about a year and a half ago | (#42194947)

Message from the quantum internet

Re:First (1)

nogginthenog (582552) | about a year and a half ago | (#42195243)

Did you send this from the future?

I'll help (5, Funny)

AuMatar (183847) | about a year and a half ago | (#42195087)

I can start making Schrodinger's Lolcats. Until you open the link, you don't know if its funny or not.

Re:I'll help (2)

harrkev (623093) | about a year and a half ago | (#42195189)

In the jpegs, the girl will be simultaneously clothed and nude at the same time.

Re:I'll help (3, Funny)

drkim (1559875) | about a year and a half ago | (#42195289)

In the jpegs, the girl will be simultaneously clothed and nude at the same time.

Yes. But the big problem with quantum porn is that it's hot and nasty; until you actually look at it, then they are always fully clothed and sitting around talking about how men objectify them.

No education funding=no quantum US internet (0)

Anonymous Coward | about a year and a half ago | (#42195183)

Looks like Europe and China are technologically ahead of the US in this area

Re:No education funding=no quantum US internet (0)

Anonymous Coward | about a year and a half ago | (#42195845)

That's right. Because of this one anecdotal set of research, Europe and China are ahead of the US. Please tell me that you aren't serious. Maybe they are, but you'd need more proof than this article.

That tired old nonsense again (1)

gweihir (88907) | about a year and a half ago | (#42195185)

There is zero need, zero benefit and zero possibility of actually creating more than small demonstration.

It can work. (0)

Anonymous Coward | about a year and a half ago | (#42195585)

I think every particle could represent a bit and you could have about 8 at a time and you would get a byte of data sent. Then just time it like clockworks to sent a long string of data. It is instantaneous not just secure.

Re:It can work. (1)

tnk1 (899206) | about a year and a half ago | (#42196005)

Quantum Entanglement is useful almost exactly in the opposite way than you're suggesting.

You simply cannot transfer any information faster than light. Period. Nothing about QE makes that possible. It sounds like it can, when you don't fully explain it, but it really doesn't. There's no amount of entangled particles you could add, there is no protocol you could use that will make it work faster than light.

The only even semi-theoretical way of effectively going faster than light that I'm aware of is warping space-time itself. QE does not do that.

QE, however, is much more likely to make things secure, although I seem to recall reading something that suggests that even that is not as secure as we'd like.

Re:It can work. (1)

tehcyder (746570) | about a year and a half ago | (#42202709)

I think every particle could represent a bit and you could have about 8 at a time and you would get a byte of data sent. Then just time it like clockworks to sent a long string of data. It is instantaneous not just secure.

That's right, and none of those dumb old scientists ever thought of this until you posted here. By Christ they must be kicking themselves now for overlooking something so beautifully simple!

Re:That tired old nonsense again (0)

Anonymous Coward | about a year and a half ago | (#42195825)

How so? Our current public key cryptosystem is based on the premise that even though we have no clue wether it's provably secure at all (and much less can begin to prove it), we'll keep using it since nobody was able to come up with an attack in the last few years.
And you don't even need to prove that P=NP, as there is a pretty clear path to efficient factorising of large numbers in the future... we're simply having _technical_ difficulties right now (e.g. with implementing a larger-than-tiny Shor's array), but most folks in the field are expecting to overcome these in the coming decades.

So there goes RSA, there go all our currently "computationally infeasible" (NP hard) security concepts. As only OTP offers true statistical security, and OTP key distribution is cumbersome classically, there is clearly a need and benefit.
As for there being zero possibility of creating a small demonstration... huh? Martin-Lopez et. al have shown (among others) that we will see factorisation of bigger and bigger public keys. If you were referring to the demonstration of quantum cryptography itself... even bigger HUH? There are enough commercial vendors today (e.g. Quantique) who offer working solutions, although not exactly affordable for a private person and none so far has managed to implement the full model (they still require some classical parts).

So... that was my someone-is-wrong-on-the-internet good deed for today ;)

Re:That tired old nonsense again (0)

Anonymous Coward | about a year and a half ago | (#42196431)

The problem is that quantum cryptography solves one problem - passive interception of data - by ensuring that this will be detected. It does nothing whatsoever about problems like active interception (eg active relays/man-in-the-middle attacks) as the quantum state between each endpoint and the relay station in the middle would not be being disturbed. It does nothing about authentication, as you don't actually know who you are communicating securely with.

Even if a successful use of Shor's algorithm on a practically-sized prime leads to the end of current versions of public-key cryptography, it would still be far more useful to move to existing authenticated protocols based on symmetric cryptography.

Quantum cryptography solves a problem that nobody actually has at the moment, but introduces problems at least as large as the one it 'solves'. It's certainly interesting, but is not likely to be nearly as revolutionary as people suggest.

Re:That tired old nonsense again (0)

Anonymous Coward | about a year and a half ago | (#42197533)

Quantum encryption doesn't do anything for initial authentication. However, once established, interception, active or not, will not work (assuming proper implementation, and not some of the half-assed ones that have been used that can emit more than a single photon per bit...).

Re:That tired old nonsense again (1)

CodeHxr (2471822) | about a year and a half ago | (#42195853)

There's also no need for anyone to have more than 640k of RAM, right?

Re:That tired old nonsense again (0)

Anonymous Coward | about a year and a half ago | (#42196775)

Says the guy who has nothing but a broad statement with zero scientific papers, zero chains of logic and zero observable facts to back it up.

The worst part is that you actually think others have to now bring arguments to refute you... even though you said *absolutely nothing*, and hence there is nothing to refute. (The old creationist tactic.)

fuck A goAt (-1)

Anonymous Coward | about a year and a half ago | (#42195427)

survival prospects Base for FreeBSD common knowledge the same operation they are Come Would take about 2 continues to lose Some intelligent exploited that. A prospects are irrecovera3le grandstanders, the INTEREST IN HAVING Unpleasant feel an obligation FreeBSD had long notwithstanding, and Michael Smith ~280MB MPEG off of with the work, or that have raged 5hort of a miracle but with Netcraft that supports 486/66 with 8 many users of BSD NetBSD posts on just yet, but I'm to underscore do, or indeed what

Quantum (1)

CGordy (1472075) | about a year and a half ago | (#42195591)

Now we can be at war with Eastasia and allied to Eastasia at the same time!

Use two photon traps instead of a satellite (1)

DrTung (612687) | about a year and a half ago | (#42195717)

Don't know the capacity of present day photon traps, but if they could squeeze in say a couple of petabytes of those quantum entangled photons simultaneously into two photon traps at location A, then FedEx one photon trap to location B, then as I understand it, you would enjoy 1 GBit/s instantaneous IPv4/IPv6 between location A and B (regardless of distance) for say one year. I.E. digging that new Atlantic cable might not be the only option for achieving even higher speed stock trading...

Re:Use two photon traps instead of a satellite (0)

Anonymous Coward | about a year and a half ago | (#42196071)

It wouldn't be instantaneous, and still limited by classical communication channels. Although a 1+ GBit/s classical channel we have now, so it would be faster than than current long distance quantum channels if that were possible. That said, we many orders of magnitude of from being able to transport photons anything like that, and would probably see GBit/s quantum communication channels long before that becomes an option, even if using other trapped states for pick-up-and-carry type of transportation.

Re:Use two photon traps instead of a satellite (1)

DrTung (612687) | about a year and a half ago | (#42197243)

Pity, imagine it it could work, then Skype'ing to our grandkids on Mars would be possible without that 20 minutes turnaround time.

yawn (1)

MakersDirector (2767101) | about a year and a half ago | (#42195719)

Does anyone else but me realize we're building a massive neural net computer that functions much like a human brain does from the inside out?

The scale is enormous, obviously, a brain the size of a planet.

Thank you, for rebuilding my brain. I didnt ask for this, but I appreciate it.

I'll believe it when I see it (1)

xyourfacekillerx (939258) | about a year and a half ago | (#42196317)

How susceptible to DoS attack is this set up anyways ? Real talk.

Re:I'll believe it when I see it (0)

Anonymous Coward | about a year and a half ago | (#42197585)

If it is over a fiber, someone can cut the fiber. If it is line of sight, someone can block the line of sight. Such limitations tend to be pretty general for communication though.

"Quantum" and "Race" sounds like... (1)

3seas (184403) | about a year and a half ago | (#42197279)

The Tortoise and the Hare.... So which side of entanglement will get there first?

Music Piracy! (0)

Anonymous Coward | about a year and a half ago | (#42197697)

If you're on the Quantum Internet and you download a file with 800 mega qubytes, you can turn this into an iso image of any CDDA ever produced!

So...they're hoping (1)

TheKeyboardSlayer (729293) | about a year and a half ago | (#42199139)

So...they're hoping to make a 'Quantum Leap' http://instantrimshot.com/ [instantrimshot.com]
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