This article aims to explain what Quantum computing is and it’s implication for cryptographic systems we use today for protecting confidentiality, integrity, availability of data and non- repudiation of transactions. Complex algorithms and long cryptographic keys help crypto analyst to achieve these goals.
What is Quantum Computing?
Quantum computing is about processing information stored in individual atoms, electrons, ions and photons.
What makes it revolutionary and a big step change to our current computing power is that, it overcomes the restriction of binary digital electronic computers based on transistors that we use today. Our computers today require that “data be encoded in binary digits (bits), each of which is always in one or two finite states (0 and 1),” Quantum computing uses quantum bits called Qubits which can exist in a super state with zeros and ones occurring together. This is a phenomenon called the superposition of states. In this state, a quantum computer can carry our parallel processing at a faster rate than our current processors. https://en.wikipedia.org/wiki/Quantum_computing
Today, the BBC announced a significant breakthrough by a team of researchers in Canada. The team was able to suspend two electron particles in a silicon chip therefore making it a quantum chip. The quantum computer, using a quantum chip performed calculations that provided the same results as the modern computers we use today. It is worth noting that the electrons in the silicon chip was aligned using microwave energy. The implication of this breakthrough is that, it may now be easier to control and manufacture Quantum computers. A step closer to an exponential increase in computing power as we know it today with the additional processing power provided by superposition.
Quantum computing will deliver a huge boost to crypto analysis
The exponential leap in computing power promised by the quantum computer poses a threat to our current encryption technology whose integrity depends on would be crypto crackers not having enough computing resources to break cryptographic algorithms. The measure of the strength of a crypto system is the effort in terms of cost/and or time required to mount a successful brute force attack on it. This is called a workforce factor. Quantum computing will significantly reduce the work force measures of our current crypto systems.
“It should be said that all cryptographic systems have a limited life span due to Moore’s law which states that advancement in computing power doubles every two years.” Quantum computing, when it truly arrives will more than double processing power, it is a paradigm shift and step change.
In a scenario where quantum computers hit the market or become easily available in the next 10 years, it will pose a serious threat to current cryptographic techniques we use for transactions from block chain to Public key infrastructure (PKI). As things stand, it is now a known fact that PKI already has an expiry date closer than we first thought due to this development. Our E Commerce, financial and email systems depend on PKI encryption. All these can be compromised by teams having the right processing power to do brute force computations. The NSA is already thinking of stronger encryption that will withstand the computational power of quantum computers. Work is also underway by NIST to find post quantum algorithms for encryption.
Quantum computers are good at solving factorisation problems
The issue is factorisation- Factorisation involves solving the issue of working from the result of a known prime number that is derived from the multiplication of two unknown prime numbers. The PKI is based on this cryptographic principle
Shor’s algorithm, the most complex known algorithm today was applied to resolve the factorisation problem using quantum computing for prime number 15. It did it in a very efficient way using Qubits. This implication of this is that the processing power of a quantum computer makes it possible to break most known algorithms today, RSA included whose strength does not exceed Shor's algorithm
Nations states and organizations are storing vast amounts of currently encrypted data (possibly intercepted) for which quantum computing with be able to decrypt at a future date. The value of some of todays encrypted data will devalue over time as increased processing power allows decryption. This breaches one of the goals of cryptography, Confidentiality.
What to do
Follow the lead of the NSA by starting to think ahead.
All organisations with data classified as secret and confidential must put governance in place now to ensure that algorithms, protocols and key lengths are sufficient to preserve the integrity of cryptographic systems for however long to protect secrets. Known quantum computing capacities should be factored in when deciding what algorithms, protocols and key lengths to use.
It may very well be required that some very top secret data whose disclosure will cause exceptionally grave damage to nation states if intercepted now and decrypted in the near future would have to be transmitted through non digital means. Strangely, that may mean going back in time using human messengers.
Reminds me of a biblical saying, in Luke 8 verse 17, "For nothing is hidden that will not be made manifest, nor is anything secret that will not be known and come to light”. Truly cryptography has a life span for keeping secrets. Light may have come in the way of Quantum computing.
'Yemi Oluleye Bsc, ACIB, MBA. CISSP , Certified TOGAF
Consulting and Research Director at Y-Digital Technologies