Current Event: Safety of Encryption from future Quantum Computers
All of us feel a certain kind of safety when we are dealing with credit cards, online banking and any other transaction or process which should be secure because we know that our personal information is protected by cryptographic systems. Yes there are occasions where these security measures are circumvented by exploiting other weaknesses in the system or by just stealing private information. However we take comfort in the idea that these cryptographic systems are unbreakable given feasible computing time and resources. However, a recent article talks about the threat of ‘Quantum Computers’ which could potentially compromise the security of these systems used by businesses and banks around the world.
The laws of Quantum Physics say that a subatomic particle can exist in two states at the same time before you look at it. Similarly in a Quantum computer, a bit can be both zero and one at the same time. A string of eight bits can therefore represent all numbers between 0 to 255 at the same time. Scientists say that a Quantum computer can solve a problem in months that would take conventional computers millions of years. For example, public key encryption which is widely used on the Internet creates codes by multiplying two prime numbers together. What makes the code hard to break is that working backward from the product of the two primes is extremely hard. A Quantum computer would be able to solve this problem in a feasible amount of time because it will be able to look at multiple solutions at the same time.
In the article, Professor Oded Regev of the Tel Aviv University’s school of Computer Science stresses the importance of the development of a new cryptographic system that will be able to maintain its integrity even when Quantum Computers will be available. Several reasons for this are the security of bank and financial information, medical records, and digital signatures that would become visible if an attacker hacked into this RSA encrypted data. The article predicts that Quantum computers will be a reality in the coming decade which would make it easy to crack the RSA cryptosystem. Hence the article emphasizes the need to start thinking of systems that could replace RSA.
http://www.sciencedaily.com/releases/2009/02/090205110609.htm
Comment by jonfung
February 13, 2009 @ 3:02 pm
From what I’ve heard, quantum computers are considered possible endgames both by cryptographers and cryptanalysts. The fact that quantum computers would be able to do integer factorization far easier than normal computers can would break many encryption algorithms. However, there is work being done in quantum cryptography so maybe not all is lost. If we don’t come up with a solution resistant to quantum computers, then eventually the internet may become a place where you can’t do anything securely, making it far less useful.
Comment by Andreas Sekine
February 13, 2009 @ 5:50 pm
There has been research stating that quantum cryptosystems would be even more secure than modern ones. It’s been suggested that such a system would not fall victim to wiretap, and that an eavesdropper couldn’t determine the quantum state of the systems, so unconditional security would be theoretically possible.
However, since this article is discussing the benefits of a hypothetical cryptosystem, it isn’t exactly like we can count on it to solve all our problems. This cryptosystem assumes ubiquitous use of quantum computers for anyone wanting to communicate securely. It then still remains an open problem of finding a cryptosystem which works for classical computers, in the presence of malicious users in possession of a quantum computer.