One method that is employed to secure communications on the Internet is the use of Secure-Socket layers (SSL). This is the mechanism that is used to protect information that flows over the Internet, whether it be when buying something from Amazon.com or whether it occurs when you are using a Virtual Private Network (VPN) to connect to your work place. Without cryptographic ciphers, the idea of SSL or a VPN could never exist.
Cryptographic ciphers are mathematical equations that allow a pseudo-random key to be created between two endpoints, like your computer and Amazon.com to make sure that nobody is listening in on the exchange to acquire your Credit Card information.
Standard cryptography ciphers are comprised of binary bits, meaning that there are only two states, 0 and 1. These can eventually be broken. One of the believed ways to combat the eventual breaking of ciphers and hashes is the use of Quantum cryptography.
Quantum Cryptography utilizes some of the same principles as standard cryptography, except it uses four states instead of the binary two. The addition of two states makes breaking the ciphers, significantly more difficult to achieve.
For instance, with binary, let us say you know that the string you are trying to break is 10-bits long. Each bit is either going to be a 0 or a 1. This means that you have up to 1,024, or 2 ^10, potential possibilities to try before breaking it. Breaking this key will not take all that long with today’s computers. Similarly, let us take a quantum bit with 4 different states. If you have the 10-bit quantum string to break, you will have to try up to 1,048,576 different possibilities in order to break the cipher. Let’s try a longer string, say 25-bits long. With a 25-bit string, for binary, you may have to try upwards of 33,554,432 possibilities. With a quantum-string of 25-bit it will take 1.12589991 x 10^15 (that’s 15 decimal places) or approximately 1,125,899,910,000,000 different possibilities. That is a 1.12 Quadrillion possibilities. As you can see, quantum cryptography should be more secure. Well this may not be the case any longer, but do not lose hope yet.
PhysicsWorld.com has an article stating that hackers have been able to acquire keys used within cryptography to secure a session. Quantum cryptography uses photons, instead of electrical signals, to communicate and achieve the four states needed. This process is achieved through the use of photo receptors.
There is a fundamental law that acts upon Quantum-mechanics. It is the ‘Quantum-Mechanical Principle’. It states that if any portion of a proton is measured, it affects the entire system due to fact that merely measuring the energy within the photon will alter the entire system.
When a photon is received it is processed by the photo receptors and then subsequently processed through the other electronics in the system.
The potential compromise of the key comes by having an intermediary third-party flood the recipient with light. Since the photon receptors act much like human eyes, they are basically blinded and cannot see individual photons but can still see the overall picture. This way, the intermediary can choose to send only the correctly measured photons to the recipient. Thereby, allowing both the originator and recipient to create a secure key, yet the intermediary also has a copy of the key.
This is not the end of quantum cryptography though. Researchers believe that they can combat this by placing a single-photon detector in front of the receptors of the recipients in order to test individual photons. If there is a significant number of failures when trying to read the receptors, then the two endpoints will know that there is an intruder on the line and can close the discussion.
Quantum cryptography is still being finalized and worked out to combat as many of the current-day vulnerabilities and make it more secure before it is rolled out en masse. Not to mention, waiting until the price comes down to more reasonable levels.
Photo Credit goes to NASA