Will Quantum Computing bring Blockchain to its knees?

 

Blockchain is a decentralized network of computers/nodes that uses cryptographic encryption. And on the contrary, Quantum computing has been invented to solve very complex problems which cannot be solved by the conventional computers. Thus, do Quantum computing poses threat to blockchain? What if Quantum computing breaks the encryption methods used in the Blockchain?

Quantum computing is a technology that harnesses the laws of quantum mechanics to solve problems too complex for the average computer. While we are still years away from mass adoption, quantum computing could threaten the fabric of cryptocurrencies as we know them today. The computing power we have today does not pose a threat to encryption methods on major blockchains. However, within the next 10 to 15 years, quantum computing may be strong enough to cause sophisticated storage and transit attacks on major blockchains.

Current computing is limited to “bits” where a bit is used to carry out specified computations.

Today, bits cannot exist in two separate locations in two separate states. Meaning, a bit must always have a value of a 0 or 1. These bits can only have four possible configurations when working in pairs, 0-0, 0-1, 1-0, or 1-1. To solve complex problems with multiple variables, it would take more power and effort from a regular computer as it can only support a limited range of configurations. The Google-made 54-Qubit sycamore processor is able to complete a complex problem in a matter of 200 seconds, something that would take the most powerful classical computer up to 10,000 years.

Quantum Computing differs in that it can create qubits, or bits that can co-exist in states of both 0 and 1 at the same time. An individual qubit can exist in the four variations of 0 and 1 at the same time. With each added qubit, the processing speed of that computer grows exponentially by 4.

Now, what is the hurdle?

For instance, a storage attack is one way that a Quantum Computer can exploit the encryption and security of crypto wallets. A storage attack is when a hacker breaks the encryption behind a wallet with its private key on a public ledger.

It is estimated that it would take 1 billion qubits to be able to break the encryption behind a bitcoin wallet to uncover its private key, and the most powerful quantum computers can only handle 50-100 qubits.