Cryptocurrencies and quantum computing
Many of the cryptocurrency and blockchain enthusiasts are people who are up to date with the latest technological advancements. They follow the news regarding new devices, inventions, and solutions. One of those ground-breaking technologies is quantum computers. Last year, during our visit on Web Summit we had a chance to see a prototype machine. These computers are considered by many blockchain supporters as a threat to the whole environment. Are they right to state so?
Is quantum Computing a threat to Bitcoin?
1. What is quantum computing?
The quantum computers are true game changers for processing data. Their processing power and speed is way beyond capabilities of most (if not all) traditional computers, including the supercomputers we currently have. The main difference between traditional computers and quantum ones is that the first ones process data in the binary system (either 1 for "on" or 0 for "off"), while the latter one has so-called quantum superpositions (both at the same time). This raw computing power can be used for number of purposes. When we asked the IBM representatives during the Web Summit for giving us examples, they claimed that main uses for now are:
- processing big data
- virtual experiments for entities related to chemistry, healthcare, biology or even agriculture
- making forecasts and predictions
2. Can blockchain be force hacked?
Yet with this enormous computing power, many cryptocurrency users are afraid that this could mean blockchain can be secure no more. From the very beginning, blockchains are designed to be encrypted on such advanced level, that it is physically impossible to be hacked. But with such computing power, technically quantum computers can be capable of breaking the encryptions by brute force (so-called force hack).
And this is where Satoshi Nakamoto whitepaper was a step ahead of its time and predicted such thing happening. If a quantum computer would indeed be able to break into the blockchain it could not change the data in the whole blockchain, due to the mining pool records spread among the mining rigs. The only way to do so would be via 51% attack, and apply only to new transactions, not old ones which usually are hard-coded into the cryptocurrency software. This means the quantum computers at this moment would need to hack 51% of mining rigs at the same time. Bitcoin, therefore, is safe, by the pure amount of mining rigs is resistant to such hack.
Nevertheless, a different thing could apply to private keys and wallets. There is theoretically a small timeframe during which quantum computers could be capable to calculate a private key from the public key and replacing forged signed transaction. As well, the quantum computers could be able to break the private keys to wallets and empty them. Still, with the current level of protection of Bitcoin encryption, the quantum computers will become capable of doing so in no less than a decade. One should bear in mind that these computers are not available to the public, and cost per unit is usually multi-million one. They require specific infrastructure and usually are just rented on producers premises (like IBM does) to selected parties. Potential hackers therefore are not expected to have access to them for the next few decades.
3. What methods of protection against quantum computers are available now?
Luckily, we already have a number of projects and companies working on countermeasures for quantum computers to make Bitcoin secure.
One of them (and the easiest one) would be to simply use a different public key for each transaction. Then, the extremely limited time available for breaking the address (namely between the moment of sending transaction and putting it into a block) would be an effective form of defending from quantum computers.
Quantum Resistant Ledger Project style. The main goal of it is to provide a user with one public key, yet each private key is a single use generated one.
Another one would be the solution already provided in IOTA blockchain - where each pair of public and private keys is unique.
4. Can we use quantum computing for securing blockchain?
Another is to go further by introduction quantum-secured blockchain. This would mean the total hard fork of Bitcoin based on quantum mechanics using advanced quantum cryptography, by such solutions as quantum key distribution (by the very nature of qubits the third party cannot copy or even look on the information without destroying it). Another thing where quantum computing can help is the fact that only these devices can generate truly random numbers, without detectable patterns. And each day there are new projects and solutions being introduced in that field.
5. Is buying Bitcoin safe now? Can I store my BTC safely?
As we mentioned above, the Bitcoin whitepaper has predicted the number of possible future threats for its blockchain from the very beginning. Bitcoin developers are as well aware of new solutions being introduced and continuously update the BTC blockchain with forks including not only transaction speed updates but as well the safety measures.
And as of now, you can easily and safely buy BTC online, and send it to the wallet you want with no threat from quantum computers stealing your money. Although as always - Linkkoin online cryptocurrency exchange recommends you to send your Bitcoin once you bought it to your cold or hardware wallet.