Feeds

Quantum attacks worry computer scientists

Today's network admins have it easy

Top 5 reasons to deploy VMware with Tegile

Classical computers as formalised by the early giants of computer science consist, at the most basic level, of a processor, memory and a program. The processor acts on data in a predictable way and the state of the system is easily determined (this is a simplification from the original five elements - a controller, an mathematical unit, memory, and input and output units -proposed by John von Neumann in the early 1940s, while Alan Turing used four - a tape, a head to read or write to the tape, a table of inputs and outputs, and a state register - in his work during the 1930s).

Quantum computers make use of quantum physics, the rules of subatomic particles and light, to create a computing system. Where a classical computers uses binary values of 0 and 1, a quantum system can be in a state that represents either 0 or 1, or a probabilistic blend of both states, known as a "superposition," so that it has the potential to be either 0 or 1 with its value only be determined at time of measurement. These quantum bits of information, or qubits, essentially take on all possibilities until measured, when the state of the qubits collapse to an actual value.

The science behind quantum computing gets even weirder. Two particles that represents qubits in a quantum computer system - say two electrons with their up and down spin representing 0 and 1, respectively - can be entangled. That is, the states of the two particles rely on each other irrespective of the distance between them. When one electron is measured and collapses to a value, its entangled partner - whether a metre away or a light year - reacts as well. Such entanglement is a key factor in the computations that can be achieved with a quantum system.

Finally, a quantum calculation done with a certain number of qubits in essence performs the calculation on all combinations of those bits, a property that, some physicists have theorised, can only happen because the subatomic particles exist in multiple dimensions. The ability of quantum computing to attempt every possibility to a solution at the same time makes classically difficult problems, such as factoring, a snap.

However, the other side of quantum computing is that the physics makes reliable computation technically difficult. The quantum state of a particle can not be copied, a property formalised as the No-Cloning Theorem, which means that two registers in a quantum computer cannot hold copies of the same values. Measuring the state of a register also causes the value to collapse to 0 or 1, and if the qubit is entangled, means the value of the qubit's partner also becomes determined.

Such fragility makes a quantum computer a hard system in which to guarantee integrity and an easy system to corrupt through malicious attack.

Today, quantum computers are essentially at the same stage as conventional computers were at during the first half of the 20th century, with some theoretical foundations and rudimentary working hardware. Current experiments involved manipulating anywhere from 2 qubits to 13 qubits of information and working systems mainly focus on quantum key distribution for otherwise classically implemented encryption systems.

Security for virtualized datacentres

More from The Register

next story
'Kim Kardashian snaps naked selfies with a BLACKBERRY'. *Twitterati gasps*
More alleged private, nude celeb pics appear online
Home Depot ignored staff warnings of security fail laundry list
'Just use cash', former security staffer warns friends
Hackers pop Brazil newspaper to root home routers
Step One: try default passwords. Step Two: Repeat Step One until success
UK.gov lobs another fistful of change at SME infosec nightmares
Senior Lib Dem in 'trying to be relevant' shocker. It's only taxpayers' money, after all
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Snowden, Dotcom, throw bombs into NZ election campaign
Claim of tapped undersea cable refuted by Kiwi PM as Kim claims extradition plot
Freenode IRC users told to change passwords after securo-breach
Miscreants probably got in, you guys know the drill by now
THREE QUARTERS of Android mobes open to web page spy bug
Metasploit module gobbles KitKat SOP slop
BitTorrent's peer-to-peer chat app Bleep goes live as public alpha
A good day for privacy as invisble.im also reveals its approach to untraceable chats
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Saudi Petroleum chooses Tegile storage solution
A storage solution that addresses company growth and performance for business-critical applications of caseware archive and search along with other key operational systems.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
The next step in data security
With recent increased privacy concerns and computers becoming more powerful, the chance of hackers being able to crack smaller-sized RSA keys increases.