Encryption protects your data
Do you ever wonder how your online data is kept secure? That’s where encryption comes in. Encryption is a process that uses a secret code to change your data. These changes can only be decoded and read by a recipient with the proper key. Encryption is a critical tool for keeping sensitive and personal information safe. Some examples where encryption is used include credit card details, messages and emails, and even medical records. Nowadays, encryption is crucial in computing and data transfer, but its origins can be traced back thousands of years. Some of the first examples of encryption were seen in ancient Egyptian hieroglyphs and Mesopotamian writings. The Greeks and Romans later used encryption in a more formal manner. If you’re curious to learn a bit more about the origins of encryption, consider checking out our blog post on the basics of cryptography.
Current encryption methods are meant to protect our data in the context of existing computers. However, advancements in quantum computing technology could lead to the development of a computer that could break some encryption methods that are in use today.
In this blog post, we’ll talk about how quantum computers operate and how post-quantum encryption aims to be resistant to quantum computer attacks.
From bits to qubits
Classical computers, from mobile phones to servers used by large organizations, use bits (0 and 1) to compute information. Storage media (such as magnetic disk drives, flash storage, and other devices) also use bits to store information. In contrast, quantum computing, which is currently in the early stages of research and development, uses quantum bits (or “qubits”) to perform calculations. Unlike classical bits, which can only be in one of two states (0 or 1), qubits can be in multiple states at the same time. This property allows quantum computers to perform certain calculations faster than classical computers.
Naturally quantum
The field of quantum computing has potential to bring advancements to various industries, but its applications may be limited. We might be better able to understand these uses and limitations using examples in nature. For example, consider the task of finding out how efficiently water flows through a series of pipes. This might be a difficult task for a computer to calculate, and it may be easier and simpler to determine the efficiency through experimentation. In the case of the experimental approach, we are calculating the flow efficiency via natural occurrence. By constructing a series of pipes and running water through them, we can quickly analyze the efficiency of the design, no computers required!
This experimental approach is how some scientists are using qubits. They use the natural properties of the qubit particles to make certain calculations run faster. Since qubits can be in multiple states at the same time, scientists can run many calculations simultaneously. This significantly increases overall calculation speed.
A similar thought experiment could be applied to other examples, such as calculating the volume of an object by placing it in a container filled with water. The “calculation” happens in real-time when the object is immersed in the water-filled container. Once again, no computers are necessary here. In addition, we can scale this experiment up to measure the volumes of very large objects without using any more time and without requiring any computers. We are simply using the natural characteristics of water in a container.
The significant increase in speed provided by quantum computers leads to a problem for modern encryption. In today’s best encryption methods, it would take computers a very long time (on the order of billions of years, or longer) to break even a single encryption key. However, a quantum computer with enough qubits could run through many possible encryption keys at the same time, and therefore complete the calculation in less time. Such a quantum computer does not yet exist, but there is potential for some encryption methods to be broken soon if a large enough quantum computer is created.
The applications of quantum computing, as we understand them now, are typically “natural” problems which are observed in the physical universe. Applying these same principles to some of the most common computer science concepts, such as working with lists, arrays, and functions, isn’t as intuitive. In many cases, using quantum computers might be outright impossible or impractical.
Some examples of fields where it is thought that quantum computing might be beneficial include drug discovery, optimizing financial portfolios, climate prediction, and solving complex logistics problems. However, since quantum computers operate fundamentally differently from classical computers, the extent to which they will have useful applications is not currently known.
Putting a spin on protection
The mathematics used in current encryption methods are considered too complex for current computers to solve in a timely manner. In the future, it’s expected that quantum computers will be able to make these calculations and break certain types of existing encryption protections.
So, what’s being done to protect our information from quantum computers? That’s where post-quantum cryptography (also known as quantum-resistant cryptography) takes the stage. Post-quantum cryptography is just another way of saying "encryption that’s safe from both classical and quantum computers." These algorithms are designed to be secure even in the face of quantum computing, and they are intended to replace current encryption methods that will be vulnerable to attacks by quantum computers.
Post-quantum cryptography typically involves the use of mathematical problems that are believed to be difficult for both classical and quantum computers to solve. Examples of these problems include structured lattice-based cryptography and hash-based cryptography. The great thing about post-quantum cryptography methods is that they are being designed to be run on all types of devices, from high-end servers to small Internet of Things devices, and everything in-between.
Research in quantum computing and post-quantum cryptography is currently ongoing, with progress being made in all areas. There are several approaches for developing quantum computers, such as superconducting qubits, trapped ions, photonics, and topological qubits. These platforms vary in terms of their stability and scalability, but they all have the potential to be used to build useful quantum computers. At the time of writing, companies have successfully created circuit-based quantum computers which operate on the scale of hundreds of qubits.
Meet the atomic constituents
What can we do to protect ourselves and our data against the development of quantum computers and their capabilities? The US National Institute of Standards and Technology (NIST) has worked with the cryptographic community over the past several years to select the best algorithms of post-quantum cryptography standards. Four post-quantum cryptography algorithms are being standardized, and additional techniques are still being considered.
In addition to NIST’s work in standardization, the Government of Canada released its National Quantum Strategy (NQS) in 2022. The NQS aims to make Canada a world leader in quantum computing hardware and software. It also focuses on protecting the privacy of Canadians in a quantum-enabled world and enabling government and industry in the development and adoption of quantum sensing technology. The strategy makes a point to highlight that the federal government will need to work closely with researchers, industry, and other governments to ensure the security of Canadian data as we move into an era of quantum computing. Governments are still working to understand the policy implications of quantum computing. The Office of the Privacy Commissioner has a role in protecting Canadians’ privacy as these technologies advance.
As algorithms become standardized and available for implementation, it will be important for industry to begin transitioning to using quantum safe algorithms. This is especially true of data which contains sensitive and personal information. Individuals and businesses should remain on the lookout for updates regarding post-quantum cryptography and how it can be used to improve privacy protections.
Classical and quantum: An entangled world
In summary, encryption is a critical tool for protecting sensitive information in the digital world. However, the rise of quantum computing may render some current encryption methods vulnerable. Post-quantum cryptography aims to replace current encryption methods with cryptography that is resistant to quantum computing.
Overall, there is reason for optimism about the future of encryption and data security in the face of quantum computing. As research in post-quantum cryptography and related quantum computing fields continues, we can expect to see new cryptographic algorithms and technologies that are secure against quantum computers. While quantum computing may pose new challenges to encryption, it also presents an opportunity for progress and innovation in many important fields.