Article referenced: https://www.technologyreview.com/s/608041/first-quantum-secured-blockchain-technology-tested-in-moscow/
It is interesting to know that as we make new developments in technology, we face new security risks. Considering the increasing developments in quantum computing, it is impossible to not wonder about the security implications it pose. Many encryption algorithms rely and work on the basis that it is impossible to break the encryption in our current lifetime, meaning its possible to break them but the time required is too much (humans might be dead by then and apes will rule the earth, so loooonnnnggg time).
In the article referenced, it discusses about the popularity of cryptocurrencies and the security risks it faces. Quantum computing, with its super fast processing speed, will be able to make calculations which were previously deemed impossible within our current lifetime. Therefore, this means that brute force breaking of hashes would be made possible. Blockchain technology highly depends on hashing algorithm to carry out its transactions in a safe and secure manner (detect blocks that were tampered by malicious people), thus if quantum computing makes it possible to brute force hashes, the blocks are not safe anymore. So this is the problem.
Moscow scientists suggest the use of quantum computing identification mechanism to prevent this from happening. They suggest the use of photons to verify identity between the computers involved in the transactions as photons cannot be tampered with without being destroyed. Currently, the proof of method solution that they have developed, works in the principle that 1/3 or lesser of the people involved in the transactions are being dishonest (only less than 1 person out of 3 is lying). Nevertheless, this is still a good beginning to what is definitely gonna be a problem in the future.
Apart from blockchains, there are many other things which might be affected by the development of quantum computing. For example, social networks use hashing to store passwords, meaning our accounts are vulnerable too. This issue is definitely a concern to security experts around the world.
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