The threat of quantum computers to Bitcoin

in #bitcoin7 years ago

I have read a couple of very interesting articles about the technological advance of quantum computing and its threats to cryptography. This should be of interest to all people using or investing in cryptocurrencies.
Currently, the development of quantum computers is still in an early stage but large companies like Google and also government agencies like the CIA are heavily investing in the technology. Experts say that there is a 17% chance of the singularity of a quantum computer emerging in the next 10 years. On the other hand technological advance is non linear, so theoretically the emergance of a quantum computer strong enough to pose a threat to bitcoin could be closer than we think.

Why are cryptocurrencies threatened by quantum computers?

The technology behind quantum computers enables much faster calculations compared to what we know from our regular PCs or even existing supercomputers. The threat to Bitcoin is that quantum technology could make it possible to derive your private keys from your public keys when you make a transaction. Once your private key is exposed, anyone who has access to it has control over your bitcoins.

How can Bitcoin defend itself?

First of all, there are different views about Bitcoins current capability to handle attacks from quantum computers. While some scientists say that the emergence of the first quantum computer will doom bitcoin, others are more optimistic. While a quantum computer could derive your private key from your public key, it would still have a hard time decrypting your public key, because this one was run through a number of one way hash functions, resistant to quantum computing. However nobody knows for sure what would really happen when the first quantum computer strong enough was used to decrypt bitcoin. Therefore, security experts suggest to upgrade the bitcoin protocol from SHA-256 to SHA-384, since the latter is a more secure form of cryptography.

In the end, as quantum computers evolve, so does the possibility to use them for safer encryption. Let's just hope that in case of an immediate threat, the bitcoin community can come to a consensus over establishing the necessary update 😅

Sources / further read:

https://medium.com/the-quantum-resistant-ledger/be-prepared-for-quantum-computing-era-bb1a9ec6cd35

https://news.bitcoin.com/is-bitcoin-at-risk-as-google-and-ibm-aim-for-50-qubit-quantum-computers/

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So far quantum computers haven't been a threat to Bitcoin but don't know about future.

I feel like the current state of quantum computing is fairly safe because these powerful computers are in the hands of somewhat benevolent companies that have no interest in stealing bitcoins. As quantum computers become ubiquitous and more people start having them, that's when the danger gets more real. I'm not terribly worried about it today, but 5 years out..yeah possibly.

Fortunately, I feel that algorithms are being developed today which will theoretically be quantum resistant. IOTA is one example of a team working toward that, granted it's still all theory.

-@mattboyd

I agree to a point. Quantum resistance will no doubt be worked on hard by a lot of people. I don't think that tech companies are necessarily going to be benevolent. Depends on their business model at the time I guess. Facebook for example could be directly threatened by things like steem. Google too. Just my humble opinion.

Actually, you made me rethink my point. I can see a path where companies will not be overly benevolent. Steem was definitely a good example. Cheers!

What about mining with quantum computers ? all blockchain algorith will slowly turn quantum

Steemit has been my first foray into the crypto-currency world. I have wanted to try before, but a couple of weeks ago I signed up. I have to admit that quantum computers have always been a worry to me. They way I see it is this...

If successful quantum attacks happen, they will be BIG news. It will collapse the system. Someone who wants to steal coin has a vested interest in the system staying intact. They will either have to stay under the radar, or not CARE about collapse. That is why I think it will be a state run program with a collapse being the actual goal. All governments see crypto-currency as a threat, so they would make a good candidate. Plus, they have the funds and science to potentially create a quantum computer capable of doing this. Food for thought. Good article.

Good point. Hiding some innovation as big as this probably won't work.

What about mining with quantum computers ? all blockchain algorith will slowly turn quantum