Quantum computing emerges as a new technology that makes use of quantum physics and several quantum-mechanical effects, such as superposition, entanglement, etc to communicate data. Quantum communication systems use quantum bits, also referred to as qubits, to represent data. Qubits do not have defined states (0 or 1), such as a typical binary digital communication system, but probabilistic fields of states allowing extreme parallelization of operations. This enables quantum computing to perform certain classes of programs faster and more secure than conventional algorithms.
Due to the nature of quantum physics, when Quantum Computing will officially and commercially be launched, it will be able to crack a large class of encryption algorithms widely used today. Classical computing modern public-key cryptographies like RSA, Diffie-Hellman key exchange, and ECC will not be secure due to the presence of quantum computer processors in the next decades. Only symmetric encryption like AES can remain reliable, switching from typical 128-bit keys to more than 256-bit keys.
Since security emerges as one of the most critical issues in the 5G era, quantum computing can pose a real threat to traditional communication systems. It may have an overall disruptive potential for the TelCo industry. At the same time, using Quantum devices can significantly improve network security. This means that Mobile Operators and Service Providers around the globe will, therefore, have to build up an efficient quantum communication infrastructure for securing their network assets.
Security Threat
When it comes to security, network operators need to think ahead to be able to support future technologies. They need to ensure that communications remain secure even after a breakthrough is made in quantum computing, and the first computers hit the market. As computing power increases and our society is highly based on ICT technology, public-key cryptography will become ever more vulnerable. Hacking is one of the main threats of the modern world. Hacking is possible on wireless but also wire-line and optical fiber communications where a man-in-the-middle may penetrate the network to intercept and obtain information.
The problem of the security of currently used public-key cryptography is that it is based on human ingenuity and mathematical algorithms that could be easily broken by future technology. According to Moore’s Law, the increase in computing power makes it increasingly easier to break public-key cryptography. Therefore, public-key cryptography is vulnerable to quantum computing, which can solve specific mathematical issues exponentially faster than classical computers.
Any conventional cryptosystem based on mathematical complexities is vulnerable to Quantum attack. Almost all existing networks use certain types of ciphers for encryption, such as Integer Factoring & Discrete Logarithms (RSA, DSA, DH, etc.). Advanced Encryption Standard (AES), especially the 256-bit version, is one of the existing public symmetric key ciphers that seems to be safe to operate with Quantum computing.
Quantum Key Distribution (QKD)
The main question of future communications is how to distribute secure key algorithms between distant parties without relying on insecure legacy public-key algorithms. In network encryption, the current weakest link is the key distribution based on public-key cryptography. Quantum Key Distribution (QKD) tackles this problem since it is a technology that uses Quantum Physics to secure the distribution of symmetric encryption keys. For example, quantum cryptography solves the problem of key distribution by allowing the exchange of a cryptographic key between two remote parties with security guaranteed by the fundamental laws of physics and not human-applied mathematical models. With QKD, when a third party tries to intercept information in the middle, the sender and receiver will know it.
QKD Alice and Bob example
The quantum key distribution mechanism creates secret random numbers communicated between two parties. These numbers are typically used as cryptographic session keys to support secure communication across insecure networks. The core idea in QKD is the use of quantum mechanics to detect the presence or absence of an eavesdropper. In a typical quantum system example, Alice and Bob are the sender/receiver, and Eve is representing an eavesdropper.
Alice and Bob exchange quantum states during the protocol exchange. The eavesdropper Eve, if present, will measure the states being exchanged, in an attempt to learn the data values. This measurement, as it was observed, results in an immediate collapse of the quantum state. Sensitive statistical methods can reveal the changes caused by Eve’s intervention, even when she tries her best to limit her impact on the system. Fundamentally, the more she learns, the higher the chances of her presence being detected. Over time, the odds of her going undetected are extremely small. This means that the QKD mechanism can instead be seen as the typical example of a quantum sensor network, rather than a distributed numeric computation.
How quantum computers work
Quantum computing is a model of computing that uses quantum physics to compute in a different manner than conventional machines do, such as breaking RSA and elliptic curve cryptography efficiently. Quantum computers are based on quantum mechanics, the branch of physics that studies the behavior of sub-atomic particles, which behave genuinely randomly. Unlike classical networks, which operate on bits that are either 0 or 1, quantum computers are based on quantum bits, which can be both 0 and 1 simultaneously. This state of ambiguity is called superposition. Physicists discovered that in this microscopic world, particles such as electrons and photons behave in a highly counterintuitive way. This means that before you observe an electron, the electron is not at a specific location in space, but in several locations at the same time. This state is called superposition. But once you observe it, it then stops at a fixed, random location and is no longer in superposition. This observation, called measurement in quantum physics, is what enables the creation of qubits in a quantum computer.
However, proper quantum computing communication can be set up due to another phenomenon that is called entanglement. Two particles can be connected (entangled) in a way that observing the value of one gives the value of the other, even if the two particles are widely separated. This “wide separation” can either be kilometers or even light-years away from each other!
Quantum Computing today
Today’s commercial systems examples are D-Wave, a quantum annealer developed by D-Wave systems that is a simple version of a quantum computer. Lockheed-Martin and Google are among the early users. IBM has also launched IBM Q, a 16 qubit processor and a public quantum cloud access with Software Development Kit, tutorials on quantum computing and simulations available to everyone.
Currently, quantum random number generation chips can be quite small in size. This means that these chips will be able to be used in various IoT devices, as well as autonomous vehicles, smartphones, and drones. Almost all internet services and businesses will be affected by quantum computing and its risks. Quantum computing consists of the actual quantum computer, which is the hardware, composed of quantum bits. Quantum algorithms are the software that runs on it and is composed of quantum gates. Once large scale quantum computers become available, fast market penetration is expected. The rise of quantum communications will, therefore, be driven by as-a-Service offerings by network providers.
