Will quantum computing kill crypto?

[crypto33]

With the steps forward that quantum computing is making will it mean the end of crypto as we know it once quantum computing become a reality?

I mean it effectivly makes encryption useless, someone with a quantum computer could just brute force a private key from a public key in no time. This will kill every crypto currently out there.

Do you think we will see new quantum cryptos released once the technology is ready? Or do you think Bitcoin will adopt a new layer of quantum security if that is even possible?

I'm by no means an expert on the subject but unless the good guys get their hands on some form of quantum computer before the bad guys it kind of puts a ticking timer on the whole crypto industry. That's if an extra layer of quantum encryption can even be implemented in some way for Bitcoin.

If not, then I guess we better time it just right and get the f**k outta here at the right time.

Thoughts?

[aliashraf]

With the steps forward that quantum computing is making will it mean the end of crypto as we know it once quantum computing become a reality?

I mean it effectivly makes encryption useless, someone with a quantum computer could just brute force a private key from a public key in no time. This will kill every crypto currently out there.

Do you think we will see new quantum cryptos released once the technology is ready? Or do you think Bitcoin will adopt a new layer of quantum security if that is even possible?

I'm by no means an expert on the subject but unless the good guys get their hands on some form of quantum computer before the bad guys it kind of puts a ticking timer on the whole crypto industry. That's if an extra layer of quantum encryption can even be implemented in some way for Bitcoin.

If not, then I guess we better time it just right and get the f**k outta here at the right time.

Thoughts?

It is not the way you put it. We have quantum resistant cryptographic algorithms out there, already:
https://en.wikipedia.org/wiki/Post-quantum_cryptography
I'm specially a fan of this one:
http://ieeexplore.ieee.org/document/6337933/?reload=true

Quantum computing is too immature to be considered a threat for at least this decade and when it happens to be ready, we are ways ready. Just don't panic.

[crypto33]

With the steps forward that quantum computing is making will it mean the end of crypto as we know it once quantum computing become a reality?

I mean it effectivly makes encryption useless, someone with a quantum computer could just brute force a private key from a public key in no time. This will kill every crypto currently out there.

Do you think we will see new quantum cryptos released once the technology is ready? Or do you think Bitcoin will adopt a new layer of quantum security if that is even possible?

I'm by no means an expert on the subject but unless the good guys get their hands on some form of quantum computer before the bad guys it kind of puts a ticking timer on the whole crypto industry. That's if an extra layer of quantum encryption can even be implemented in some way for Bitcoin.

If not, then I guess we better time it just right and get the f**k outta here at the right time.

Thoughts?

It is not the way you put it. We have quantum resistant cryptographic algorithms out there, already:
https://en.wikipedia.org/wiki/Post-quantum_cryptography
I'm specially a fan of this one:
http://ieeexplore.ieee.org/document/6337933/?reload=true

Quantum computing is too immature to be considered a vulnerability for at least this decade and when it happens to be ready, we are ways ready. Just don't panic.

Great resource! Thanks for sharing that. So I take it that if post-quantum cryptography is already being worked on in order to be prepared then that extra layer of security can be written into the Bitcoin code, even that far down the road?

Panic over I guess 

[ranochigo]

I mean it effectivly makes encryption useless, someone with a quantum computer could just brute force a private key from a public key in no time. This will kill every crypto currently out there.

No. If quantum computing does become a reality, the time taken to bruteforce a private key to a public key will decrease substantially but not to that much magnitude.

Do you think we will see new quantum cryptos released once the technology is ready? Or do you think Bitcoin will adopt a new layer of quantum security if that is even possible?

Yes.

I am not currently aware of any development on such an algorithm for now. With reference to my initial post, the security risk of this can be easily mitigated. As long as people do not reuse addresses, it is quite hard for anyone to profit using a quantum computer. Speaking of profits, the cost of operating one is quite expensive and not everyone can have their hands on it.

[aliashraf]

Great resource! Thanks for sharing that. So I take it that if post-quantum cryptography is already being worked on in order to be prepared then that extra layer of security can be written into the Bitcoin code, even that far down the road?

Bitcoin is inherently resistant to quantum computing as it does not disclose the public key, instead it hashes it twice! So the attacker literally has no chance to 'derive' the private key even armed to a super quantum computer like in a science fiction.

So far so good, BUT when one 'spends' his wallet, eventually has to disclose his/her public key and if s/he accidentally tries to use the same address again, well, from here on the alarming flags should be raised if there are powerful enough QCs commercially available.

Note:
In the limited interval between the time of the spend Tx even for the brand new addresses, until they get confirmed, there is a window for the QC attack to compromise the private key and generate another transaction with higher fee and priority and steal funds, taking advantage of this window needs very huge QCs to break the code very fast, not like few days, but few seconds. Such QCs not likely to be built ever.

Anyway, when it comes to upgrade, there will be a soft fork, implementing new address types and thus new cryptographic algorithms. After  the fork, all new transactions will be safe in heaven, the only weakness will be the elder UTXOs with used addresses, though it will be the holders' responsibility to renew their wallets asap.

Panic over I guess 

[crypto33]

I mean it effectivly makes encryption useless, someone with a quantum computer could just brute force a private key from a public key in no time. This will kill every crypto currently out there.

No. If quantum computing does become a reality, the time taken to bruteforce a private key to a public key will decrease substantially but not to that much magnitude.

Do you think we will see new quantum cryptos released once the technology is ready? Or do you think Bitcoin will adopt a new layer of quantum security if that is even possible?

Yes.

I am not currently aware of any development on such an algorithm for now. With reference to my initial post, the security risk of this can be easily mitigated. As long as people do not reuse addresses, it is quite hard for anyone to profit using a quantum computer. Speaking of profits, the cost of operating one is quite expensive and not everyone can have their hands on it.

Ok I understand, I guess it's always hard to predict the capability of future technology but even so sounds like it wouldnt be an issue/is easily overcome.

Thanks for helping me clear that one up in my own head!

[crypto33]

Great resource! Thanks for sharing that. So I take it that if post-quantum cryptography is already being worked on in order to be prepared then that extra layer of security can be written into the Bitcoin code, even that far down the road?

Bitcoin is inherently resistant to quantum computing as it does not disclose the public key, instead it hashes it twice! So the attacker literally has no chance to 'derive' the private key even armed to a super quantum computer like in a science fiction.

So far so good, BUT when one 'spends' his wallet, eventually has to disclose his/her public key and if s/he accidentally tries to use the same address again, well, from here on the alarming flags should be raised if there are powerful enough QCs commercially available.

Note:
In the limited interval between the time of the spend Tx even for the brand new addresses, until they get confirmed, there is a window for the QC attack to compromise the private key and generate another transaction with higher fee and priority and steal funds, taking advantage of this window needs very huge QCs to break the code very fast, not like few days, but few seconds. Such QCs not likely to be built ever.

Anyway, when it comes to upgrade, there will be a soft fork, implementing new address types and thus new cryptographic algorithms. After  the fork, all new transactions will be safe in heaven, the only weakness will be the elder UTXOs with used addresses, though it will be the holders' responsibility to renew their wallets asap.

Panic over I guess 

Of course, I didnt even think about the fact the public key is already hashed!

Glad to hear our Bitcoin will be safe from the world of science fiction.

I think a long Sunday afternoon must have taken it's toll, my imgination has been for a good wonder today...

Thanks for the info though!

[ranochigo]

Of course, I didnt even think about the fact the public key is already hashed!

Glad to hear our Bitcoin will be safe from the world of science fiction.

I think a long Sunday afternoon must have taken it's toll, my imgination has been for a good wonder today...

Thanks for the info though!

Unfortunately, in the earlier stages of Bitcoin, P2PK was implemented instead of P2PKH. The earlier transactions, specifically those that were mined to were vulnerable with the default implementation using P2PK.

That includes the genesis block and many addresses with transactions around that time.

Those addresses with 50BTC can potentially be vulnerable.

[crypto33]

Of course, I didnt even think about the fact the public key is already hashed!

Glad to hear our Bitcoin will be safe from the world of science fiction.

I think a long Sunday afternoon must have taken it's toll, my imgination has been for a good wonder today...

Thanks for the info though!

Unfortunately, in the earlier stages of Bitcoin, P2PK was implemented instead of P2PKH. The earlier transactions, specifically those that were mined to were vulnerable with the default implementation using P2PK.

That includes the genesis block and many addresses with transactions around that time.

Those addresses with 50BTC can potentially be vulnerable.

Really, I wasnt aware of that. That would surely be profitable for someone if they could exploit that vulnerability in the early blocks. At least it wouldnt bring down Bitcoin as whole though....

[simik]

Also, the moment you spend bitcoins from an address you reveal that address's public key. Not a problem, if you never reuse an address (which is how most wallets work now, creating new change addresses for each tx). Although if quantum computers are fast enough to break a private key in a few minutes to an hour, you could potentially take any tx from the mempool with a fat public key, reverse its private key, build a new tx spending the funds to your address and replace the old one with replace-by-fee.

[CryptonomyCapital]

It wont be soon, to decipher the secret key for an acceptable time, you need to have a computer with 100 million qubits, and now only a computer with 49 qubits is being developed.

[legendsneednotags]

It's going to take some time.

[skyline247]

It is crazy just how many things scientists have considered "impossible", only for them to be achieved sometimes centuries earlier than predicted. One recent example is AlphaGO. With that said, I wouldn't put anything past the realm of possibility, but with the amount of money invested in Bitcoin globally it is unlikely that if this were to happen we wouldn't find a solution.

[aliashraf]

It is crazy just how many things scientists have considered "impossible", only for them to be achieved sometimes centuries earlier than predicted. One recent example is AlphaGO. With that said, I wouldn't put anything past the realm of possibility, but with the amount of money invested in Bitcoin globally it is unlikely that if this were to happen we wouldn't find a solution.

The main threat, as have been mentioned earlier in this topic, is an imaginary multi million qubit quantum computer being so powerful that can crack a disclosed public key while its container (a spend transaction) is stuck in the mempool (few minutes). It is mainly due to the fact  that this hypothetical crack wont compromise the wallet as a whole (we re-use our wallets).

HD wallets are de-facto standard and commonly used now and they secure the process in a way that  the attacker MUST complete its mission in the short time frame in which a transaction is publicly announced and not confirmed yet. The trick is that once the confirmation takes place, compromised public and private keys will become useless, the remaining balance has mowed to a fresh, although dependent, new public/private pair of keys which their master private key is well secured by the owner (hope so) and the master public key have not to be exposed ever.

For the fictional ultra-super quantum computer giant case, the solution is out there with quantum resistant cryptography, it is just about implementation and a soft fork for which we have a lot of time, say 1-2 centuries. It really takes that long with any measure to have multi million qubit quantum computers around.

Conspiracy theories have been proposed that NSA or CIA have access to much powerful QC tech than what is publicly disclosed, while it is disputable and controversial and one can ask that how far they can go, anyhow, in practice, they can't  use their hypothetical "super power" against bitcoin even once, because by doing this, they will disclose their access to such a technology and escalate competition and research for countermeasures.

[jackcole]

Good thought. Personally I think blockchains will be the way to go, since banks will probably lag in the update to quantum resistant security measures. Communities like these are faster at adopting such technologies.

[pey]

No, because quantum is still in early stage of development, and with quantum computing, also quantum cryptography will be developed.

[btctousd81]

it will not kill it, but crypto's will have to adapt to quantum computing.,

[crypto33]

Glad to hear most people think that Bitcoin will survive. I suppose its a bit of a guessing game but for now at least we are on top of any potential changes

[AK47-]

Quantum computing is still in its starting phase. It will still need couple of decades to become a threat to cryptocurrencies. I read it somewhere that at present quantum computing is focused upon only energy landscape issues and not on solving regular mathematical problems. We need a major revolution in our ability to build reliable qubit logic before we can even think about solving complex cryptography and that problem is nowhere near being solved at the moment.

[crypto33]

Quantum computing is still in its starting phase. It will still need couple of decades to become a threat to cryptocurrencies. I read it somewhere that at present quantum computing is focused upon only energy landscape issues and not on solving regular mathematical problems. We need a major revolution in our ability to build reliable qubit logic before we can even think about solving complex cryptography and that problem is nowhere near being solved at the moment.

Sure I get that but just look at where there internet has gone in the last 20 years. I'm sure if you went back in time 20 years today's reality would have been thought of as impossible. Technology moves at such a great rate that it would be hard to predict 5 years into the future let alone another 20.