Blockchain technology has been, in recent years, hailed as a breakthrough disruptor, poised to drive innovation in virtually every industry ranging from legacy organisations to game-changing start-ups in the new digital economy. This revolutionary technology stems from the ability of blockchain to act as a decentralised distributed ledger. It promises more secure, real-time transactions and record-keeping, making it harder for important data to be manipulated or falsified.
However, especially for public blockchains, long periods of time can be required to reach a consensus for highly secure Distributed Ledger Technology (DLTs) using current blockchain technology, and efforts to increase the speed of consensus often leads to compromised security.
In 2019, a Memorandum of Understanding (MOU) between OneConnect and SMU was signed to develop a Proof of Concept (POC) to investigate the characteristics of quantum computing for DLTs. Co-led by Associate Professor Paul Griffin from SMU School of Computing and Information Systems, the report focused on studying quantum algorithms that could augment blockchain technology to optimise and reach robust, large-scale consensus.
As part of the collaboration, SMU leveraged upon OneConnect’s business and blockchain use cases for the research work. Key resources in the R&D team helped shape and validate the research.
Harnessing the theory of quantum mechanics, quantum computing systems are designed to solve highly complex problems that cannot be solved by even the world’s most powerful supercomputers. Whilst current classical blockchains are adequate for current data volumes, as big data becomes more prevalent, quantum technology will be critical to improving blockchain technology in areas such as wide-scale consensus, efficiency for on-chain data searching, private record validation, high-speed smart contract processing and interoperability between blockchain networks.
The research team therefore taps upon quantum algorithms that could boost existing blockchain technology, with the developed POC demonstrating how these algorithms can be used in blockchain networks. The POC can then be engineered into a production-ready system for wider usage alongside advancements in quantum computing.
Here are four areas that need to be addressed for quantum technology to improve the fundamental attributes of blockchain – speed, security and size:
A pivotal advantage of blockchain technology is its ability to validate data that is almost impossible to be tampered with. And because quantum and classical consensus requires a similar number of rounds to reach the same value, big data such as social media and Internet –of-Things information could be used for consensus, without being limited to the few hundreds of financial transactions of current blockchains.
The quantum internet is a network allowing for quantum devices to exchange data. The difference between the current internet and its quantum iteration? The latter will be a virtually unhackable network, transmitting vast amounts of data at the speed of light.
The massive volume of big data gleaned from the quantum internet and its speed of transmission will accelerate and optimise large-scale consensus processes. This development would likely benefit many areas of finance including trade finance and the under-banked markets.
In theory, a shift from classical computing to the adoption of quantum computing can enhance the scalability and speed of distributed consensus, as demonstrated by the research conducted thus far. Such measures will also help improve security and potentially solve the problem of blockchain interoperability — which occurs due to the vast disparity in blockchain networks designed for different applications.
Quantum consensus addresses this pressing issue as it offers a greater variation as compared to its classical predecessor, which in turn translates into shorter timespans required for consensus to be achieved. When the shorter times that are engineered are selected, the process of consensus can potentially be accelerated.
As much as quantum computing may appear to be a viable solution to current issues relating to blockchain consensus, several challenges have to be addressed before widespread adoption can become a reality.
Unfortunately, quantum computations currently experience many sources of noise such as that from “quantum decoherence”. For example, Bristlecone, the world’s largest quantum computer processor developed by Google, is “noisier than a fire at a dynamite factory”.
As discovered by the researchers, actual quantum computers require careful configuration and noise mitigation, and this will take time to become commercially useful. Furthermore, there is much more work needed to connect quantum computers to quantum networks.