I am terrified that SHA256 or ECC will be cracked and btc will become worthless

[Kprawn]

I am not too worried about that... If Bitcoin goes down with this, most banks / credit cards and secure sites on the internet will go down too.. and if they go down, nobody can only point a finger at us.

There are other options / stronger algoriths, but they have their own advantages and disadvantages.... eg. Speed. The nice thing about technology is it's adaptability ... A lot of resources will be thrown at a

solution, if plan A fails.  .... Do not lose too much sleep over this. 

[bieberluvr]

Obviously a question Snowden could answer

[7788bitcoin]

With growing computing power this may be possible in not very near future. I think I read somewhere that even so bitcoin can be upgraded to even stronger encryption (SHA512?).

[romjpn]

Changing algorithm, yep why not. But how about the mining industry ? All those ASIC becoming useless... GPU again ?

[quantumgravity]

This is a serious problem for bitcoin. The solution is to use a Quantum Random Number Generator instead on the non-deterministic algorithms that can only create pseudo-random numbers.

[shorena]

Changing algorithm, yep why not. But how about the mining industry ? All those ASIC becoming useless... GPU again ?

Firstly sha256 is not an encryption algorithm, its a hash.

Bitcoin mining is done with sha256d (sha256(sha256(data))). There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs. Lets just assume they are 100 times better anyway. What would happen? We would have a difficulty increase. For a short time blocks would be found quicker, afterwards everything would be back to normal. This is even true should QC be 2¹²⁸ times faster, but it might still be a good idea to jump to a different hash function if the difficulty becomes to high to grow further. In this case it would require new specialized hardware. I dont think we will ever go back to GPUs.

This is a serious problem for bitcoin. The solution is to use a Quantum Random Number Generator instead on the non-deterministic algorithms that can only create pseudo-random numbers.

Nope.

[quantumgravity]

There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs

There most certainly is.

Anyway, you missed the point of this thread - it is that computer's will becoming fast enough to crack the encryption that underlies the entire protocol - not anything to do with mining. And because these encryption keys will be cracked and the solution is a QRNG.

[mcplums]

Am I being paranoid?

All of the sun's electricity is not enough to power all the computers it would take to crack a single priv key before it runs out in billions of year.

So yes, absolutely and completely Paranoid. If some Omg super mega computer that was able to work at the speed of of a galaxy full of computer would appear, well our world would end, but if it did not, BTC would still be fine, the network would switch to a new ALGO, it would probably lose some value from the scare but whatever.

I think you misunderstand. When I say 'cracked' I do NOT mean computers brute forcing their way through like you describe. I mean some maths genius comes up with a shortcut so my home pc could get a private key from a public key.

[mcplums]

There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs

There most certainly is.

Anyway, you missed the point of this thread - it is that computer's will becoming fast enough to crack the encryption that underlies the entire protocol - not anything to do with mining. And because these encryption keys will be cracked and the solution is a QRNG.

I don't think he did miss the point. Although SHA 256 isn't technically anything to do with encryption as it's a hash, if it was 'broken' it could still be a bad thing- there could be billions of valid blocks produced per second. How would the system cope with that?

[ranochigo]

There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs

There most certainly is.

Anyway, you missed the point of this thread - it is that computer's will becoming fast enough to crack the encryption that underlies the entire protocol - not anything to do with mining. And because these encryption keys will be cracked and the solution is a QRNG.

I don't think he did miss the point. Although SHA 256 isn't technically anything to do with encryption as it's a hash, if it was 'broken' it could still be a bad thing- there could be billions of valid blocks produced per second. How would the system cope with that?

Remember, Bitcoin adjusts difficulty every 2016 blocks. The faster it is, the higher the difficulty will be. Bitcoin is not about breaking the encryption, it is about finding a hash that is lower than or equal to the target. If they do crack SHA256, the difficulty would increase proportionately. Theres some other more relevant concerns about SHA256 having collsions too. However, we are still far away from that. Before it gets broken, we are likely to be on another algorithm already.

[Furio]

If sha256 gets cracked, the switch to sha512 is easily made, yet sha2 hasnt even been broken yet, so we're safe for a while

[Jeremycoin]

It would take a long time. And in that time when someone trying to crack it, Bitcoin would be more secure.
So yeah, you are being paranoid.

[shorena]

There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs

There most certainly is.

Name one.

Anyway, you missed the point of this thread - it is that computer's will becoming fast enough to crack the encryption that underlies the entire protocol - not anything to do with mining. And because these encryption keys will be cracked and the solution is a QRNG.

No, a difference source for random numbers is not the solution to a good algorithm that can caluclate the private key from a public key. If you have a good source of entropy and generate a private key with it,but I am able to find any private key given the public key. How is that going to help you?

[Lauda]

Firstly sha256 is not an encryption algorithm, its a hash.

Bitcoin mining is done with sha256d (sha256(sha256(data))). There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs. Lets just assume they are 100 times better anyway. What would happen? We would have a difficulty increase. For a short time blocks would be found quicker, afterwards everything would be back to normal. This is even true should QC be 2¹²⁸ times faster, but it might still be a good idea to jump to a different hash function if the difficulty becomes to high to grow further. In this case it would require new specialized hardware. I dont think we will ever go back to GPUs.
-snip-

It seems to me like every 2-3 months someone comes up with this topic; it's starting to look suspicious if you ask me. I'm not even sure why the forum allows this because technically they are duplicates and there are many of these "quantum is dangerous, and I'm scary threads". It is becoming tiring saying the same thing over and over again.

There most certainly is.

Not before either: 1) You die; 2) Bitcoin becomes obsolete.

I think you misunderstand. When I say 'cracked' I do NOT mean computers brute forcing their way through like you describe. I mean some maths genius comes up with a shortcut so my home pc could get a private key from a public key.

This doesn't happen overnight or else nobody would even consider using any of these algorithms. The chances of a meteor wiping everyone out are probably higher than the chances of a "genius" destroying SHA256 in the next 50 years. Should you be scared and panic? No. Focus on what is important, not on what might be.
Update:

-snip-

I didn't really mean forbid in general; there are threads about quantum related things that are only a few months ago and one could easily just ask their questions there and the discussion would become active again. However, I do understand your point as well and I do agree with you. I didn't want to write an additional post since this might be a bit off-topic to the actual thread so hopefully you will notice the update.

[teddy5145]

Am I being paranoid?

You are being completely paranoid that's all
It will take hundred of years to crack one single private key with today's technology
Maybe in the future where technology will be so advanced that computer can crack Bitcoin algorithm
But when that time come i think Bitcoin would be upgraded to something more advanced

[DannyHamilton]

- snip -
I'm not even sure why the forum allows this because technically they are duplicates and there are many of these "quantum is dangerous, and I'm scary threads". It is becoming tiring saying the same thing over and over again.
- snip -

I find that more than 99% of all new posts on this forum are just duplicates of old threads that have already been discussed and explained.

If such threads were not allowed, this forum would be a much more useful and interesting place for those of us that have been around for a while and that understand most of the basics already.

However, if such threads were not allowed, it would force newbies that actually want to learn to put effort into searching through thread history and finding answers on their own.  Newbies generally aren't that motivated, and those that already have misconceptions wouldn't even know that they have reason to go look things up.  This would result in far less people learning and understanding, and far more persistent misconceptions and misinformation being spread and not corrected.

So while all these boring and repetitive discussions make this forum much less interesting and nearly useless to me, I recognize the benefit that it provides for those that need or want more knowledge.

[jonald_fyookball]

Many threads discuss before in detail.  Search forum.

Non issue.

[maokoto]

Everything can be broken! SHA256, your credit card credentials, and even the safe in our banks. Economy even gets broken every now and then.

Question would be if SHA256 is relatively safer than most means that store value, and comparing to that I'd say it is still pretty safe.

[quantumgravity]

There is no reason to believe that quantum computers are more efficient at calculting sha256d than ASICs

There most certainly is.

Name one.

Anyway, you missed the point of this thread - it is that computer's will becoming fast enough to crack the encryption that underlies the entire protocol - not anything to do with mining. And because these encryption keys will be cracked and the solution is a QRNG.

No, a difference source for random numbers is not the solution to a good algorithm that can caluclate the private key from a public key. If you have a good source of entropy and generate a private key with it,but I am able to find any private key given the public key. How is that going to help you?

Here, just read this: https://en.wikipedia.org/wiki/Quantum_computing#Potential

It will clear up any confusion about what I'm saying, hopefully.

[DannyHamilton]

Here, just read this: https://en.wikipedia.org/wiki/Quantum_computing#Potential

Ok, I read it.  Perhaps you didnt?

It will clear up any confusion about what I'm saying, hopefully.

Nope.  It doesn't say anything about SHA256, RIPEMD160, or really any other hashing algorithm at all.