Quantum mechanics enables perfectly secure cloud computing

Jan 19, 2012
The image shows clusters of entangled qubits, which allow remote quantum computing to be performed on a server, while keeping the contents and results hidden from the remote server. Credit: EQUINOX GRAPHICS

Researchers have succeeded in combining the power of quantum computing with the security of quantum cryptography and have shown that perfectly secure cloud computing can be achieved using the principles of quantum mechanics. They have performed an experimental demonstration of quantum computation in which the input, the data processing, and the output remain unknown to the quantum computer. The international team of scientists will publish the results of the experiment, carried out at the Vienna Center for Quantum Science and Technology (VCQ) at the University of Vienna and the Institute for Quantum Optics and Quantum Information (IQOQI), in the forthcoming issue of Science.

Quantum computers are expected to play an important role in future information processing since they can outperform at many tasks. Considering the challenges inherent in building , it is conceivable that future capabilities will exist only in a few specialized facilities around the world – much like today's supercomputers. Users would then interact with those specialized facilities in order to outsource their quantum computations. The scenario follows the current trend of cloud computing: central remote servers are used to store and process data – everything is done in the "cloud." The obvious challenge is to make globalized computing safe and ensure that users' data stays private.

The latest research, to appear in Science, reveals that quantum computers can provide an answer to that challenge. "Quantum physics solves one of the key challenges in distributed computing. It can preserve data privacy when users interact with remote computing centers," says Stefanie Barz, lead author of the study. This newly established fundamental advantage of quantum computers enables the delegation of a quantum computation from a user who does not hold any quantum computational power to a quantum server, while guaranteeing that the user's data remain perfectly private. The quantum server performs calculations, but has no means to find out what it is doing – a functionality not known to be achievable in the classical world.

The image shows multiple superimposed strings of data encoded in such a way that the quantum computation can be performed on a remote server, while still securely encrypted. Credit: EQUINOX GRAPHICS

The scientists in the Vienna research group have demonstrated the concept of "blind quantum computing" in an experiment: they performed the first known quantum computation during which the user's data stayed perfectly encrypted. The uses photons, or "light particles" to encode the data. Photonic systems are well-suited to the task because quantum computation operations can be performed on them, and they can be transmitted over long distances.

The process works in the following manner. The user prepares qubits – the fundamental units of quantum computers – in a state known only to himself and sends these qubits to the quantum computer. The quantum computer entangles the qubits according to a standard scheme. The actual computation is measurement-based: the processing of is implemented by simple measurements on qubits. The user tailors measurement instructions to the particular state of each qubit and sends them to the quantum server. Finally, the results of the computation are sent back to the user who can interpret and utilize the results of the computation. Even if the quantum computer or an eavesdropper tries to read the qubits, they gain no useful information, without knowing the initial state; they are "blind."

Explore further: Quantum holograms as atomic scale memory keepsake

More information: "Demonstration of Blind Quantum Computing" Stefanie Barz, Elham Kashefi, Anne Broadbent, Joseph Fitzsimons, Anton Zeilinger, Philip Walther. DOI: 10.1126/science.1214707

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User comments : 13

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_ucci_oo
not rated yet Jan 19, 2012
Oh Boy, That explains everything.
NeutronicallyRepulsive
not rated yet Jan 19, 2012
_ucci_oo: You know... for kids!
kochevnik
3.6 / 5 (20) Jan 19, 2012
"Even if the quantum computer or an eavesdropper tries to read the qubits, they gain no useful information, without knowing the initial state; they are "blind."

Sounds a great deal like American life. Without knowing that they lost the American Revolution and declare bankruptcy every 70 years, they can't explain the real reason for the constitution, the civil war, the crash of 1929, and the WTC scalar wave implosion brashly foreshadowed by president Bush Sr. on September 11, 1991. Quite an tragic exercise in mind control, which unfortunately can't end well.
rowbyme
3.4 / 5 (5) Jan 19, 2012


Sounds a great deal like American life. Without knowing that they lost the American Revolution and declare bankruptcy every 70 years, they can't explain the real reason for the constitution, the civil war, the crash of 1929, and the WTC scalar wave implosion brashly foreshadowed by president Bush Sr. on September 11, 1991. Quite an tragic exercise in mind control, which unfortunately can't end well.

Let me guess...A Russian nutcase right?

Callippo
2.3 / 5 (3) Jan 19, 2012
Quantum mechanics enables perfectly secure cloud computing
In QM nothing is perfect due the uncertainty principle: http://www.scienc...y_broken
spacealf
5 / 5 (1) Jan 19, 2012
And in the future, the quantum computer sends back to the user:
"That was a stupid question that even I can not answer!"
The answer is as only as good as the data sent by the user.

komone
not rated yet Jan 19, 2012
@kochevnik -- and yet, apparently, with that obvious knowledge, history played out as it did. Given that evidence, one must question who is in the "bubble". All that aside, the proposal for processing in a "perfectly secure" manner is fascinating and has implications beyond those parochial concerns.
n0ns3ns0r
5 / 5 (1) Jan 20, 2012
Ooh, the cloud!
Make it easier for companies to block you from your data if they suspect one file violates copyright.
antialias_physorg
not rated yet Jan 20, 2012
The quantum server performs calculations, but has no means to find out what it is doing

That sounds like a recipe for abuse if ever I saw one.

But conceptually the idea is great. The security of quantum computing has, to date, only been broken when implementation details (i.e. hardware) could be compromised. Cloud computing has always been haunted by a lack of trust from consumers. This may alleviate that problem.

Make it easier for companies to block you from your data if they suspect one file violates copyright.

That's the beauty of what the article describes. The companies supplying the cloud functionality could never know what it is they have stored.
stealthc
not rated yet Jan 20, 2012
it's a good idea till someone figures out a way to crack it. Computers are inherently secure it doesn't matter how well you build one there is always a way to reverse engineer things. I bet the powers that be release stuff like this so they can hold the monopoly over snooping in on things like the big brother tyrants they really are.
CHollman82
1 / 5 (12) Jan 20, 2012
stealthc is right, it is a fundamental property of information theory that there is no such thing as unbreakable security. If a destination can read the data sent by a source then a third party will ALWAYS be able to find a way to also read that data, it's only a matter of how difficult it would be.
antialias_physorg
not rated yet Jan 20, 2012
If a destination can read the data

That's the beauty of the scheme: The destination doesn't read the data. They read a superposition of data which makes no sense unless you have the key - and only the sender holds the key. The destination does the computation without knowing the data in detail.

So you can neither intercept not decode the data at the computation center (you could compromise the sender's computer - but that is much harder to do than if you have the option of attacking anywhere in the entire chain of data transmission.)
Dale_Thorn
not rated yet Jan 23, 2012
There is a simple test for security: Would you bet your life on it? If you're not willing to do that, it's not secure. Take that from someone who started with cypherpunks in 1996. I've talked to the Big Guys, and done the tests. These new schemes offer "relative" security. Like your current accounts. Only more abstruse.