Topic: Creating same priv. key two times - page 2. (Read 2514 times)
There are more private keys than molecules of water on the Earth. If I picked a single molecule of water somewhere -- maybe in an ocean, or in a lake, or in the air, or in a puddle, or in my toilet -- you are more likely to guess which molecule of water I picked than to guess one of my private keys.
After I made a paper wallet for long-term saving,
I start thinking about posibility that somone can create same priv. key
in their wallet in the future.
I know that posibility for this is very small, but it exist.
If someone want to create billions and billions private keys,
he can generate someone address with positive balance.
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
I start thinking about posibility that somone can create same priv. key
in their wallet in the future.
I know that posibility for this is very small, but it exist.
If someone want to create billions and billions private keys,
he can generate someone address with positive balance.
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
A collision with any of the SHA algorithms has never been recorded. There are more possible private keys than there are grains of sand on every beach in the world. Don't be scared. Just keep you keys safe. The only theoretical issue is when quantum computing becomes a reality. But this is many, many years in the future.
hero member
Activity: 560
Merit: 509
I prefer Zakir over Muhammed when mentioning me!
The number of private keys in the universe is very big, and I've done the following calculation:
My computer have a hashrate of 4 MH/s, and it generate 650K private keys per second on vanitygen, so the estimation of private keys that can be generated by ALL the current hashing power in the world (let them be 400 PH/s for easy calculation), then the WHOLE world generate 6.5*10^16 private keys per second, compared to there are 2^160 (about 1.5*10^48) private keys that would ever exist and the 10^10 keys that may present if 10^9 people using 10 keys, then the whole world needs 4*10^22 seconds, or 1.3*10^15 years to generate a private key that someone owns, not to mention they are empty or not. So generating a duplicate private key is almost impossible.
My computer have a hashrate of 4 MH/s, and it generate 650K private keys per second on vanitygen, so the estimation of private keys that can be generated by ALL the current hashing power in the world (let them be 400 PH/s for easy calculation), then the WHOLE world generate 6.5*10^16 private keys per second, compared to there are 2^160 (about 1.5*10^48) private keys that would ever exist and the 10^10 keys that may present if 10^9 people using 10 keys, then the whole world needs 4*10^22 seconds, or 1.3*10^15 years to generate a private key that someone owns, not to mention they are empty or not. So generating a duplicate private key is almost impossible.
The number of private keys in the universe is very big, and I've done the following calculation:
My computer have a hashrate of 4 MH/s, and it generate 650K private keys per second on vanitygen, so the estimation of private keys that can be generated by ALL the current hashing power in the world (let them be 400 PH/s for easy calculation), then the WHOLE world generate 6.5*10^16 private keys per second, compared to there are 2^160 (about 1.5*10^48) private keys that would ever exist and the 10^10 keys that may present if 10^9 people using 10 keys, then the whole world needs 4*10^22 seconds, or 1.3*10^15 years to generate a private key that someone owns, not to mention they are empty or not. So generating a duplicate private key is almost impossible.
My computer have a hashrate of 4 MH/s, and it generate 650K private keys per second on vanitygen, so the estimation of private keys that can be generated by ALL the current hashing power in the world (let them be 400 PH/s for easy calculation), then the WHOLE world generate 6.5*10^16 private keys per second, compared to there are 2^160 (about 1.5*10^48) private keys that would ever exist and the 10^10 keys that may present if 10^9 people using 10 keys, then the whole world needs 4*10^22 seconds, or 1.3*10^15 years to generate a private key that someone owns, not to mention they are empty or not. So generating a duplicate private key is almost impossible.
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
This website also generate and publish private keys. www.coinfind.cf
New archive with 100,000 priv. keys are published every day.
But seems like this is for good reason, creator of that website
drop some BTC to 5 addresses for others to find.
directory.io is an old prank.New archive with 100,000 priv. keys are published every day.
But seems like this is for good reason, creator of that website
drop some BTC to 5 addresses for others to find.
it doesn't actually contain all of the private keys despite the fact that it might seems like it.
it creates private keys on the spot as you brows through the pages.
go to https://brainwallet.org/ and you can do this too, put 0000000000000000000000000000000000000000000000000000000000000001 in the "Secret Exponent" section and add +1 every time for bijillion times and you have all the private keys too.
p.s. stop visiting shady websites, you are going to be infected by malware or something.
This website also generate and publish private keys. www.coinfind.cf
New archive with 100,000 priv. keys are published every day.
But seems like this is for good reason, creator of that website
drop some BTC to 5 addresses for others to find.
New archive with 100,000 priv. keys are published every day.
But seems like this is for good reason, creator of that website
drop some BTC to 5 addresses for others to find.
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Its real, but you dont have to worry about it. They dont have a database with all keys (there is not enough storage space on the planet for that), they just generate them on the fly.
The chance is extremely low, you better worry how to keep your paper wallet safe & secure.
If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
So if two people have the same private key, they have the same wallet??If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
No, wallet is the software that handles the private keys for you.
Well you can use it to generate private keys if you want. Its also very informative with the right information and you can test yourself how likely it is to find a used private key.
Or for what do they use private keys than?
They dont store any private keys, thus they cant use them. Thats the "fake" part others are talking about. You go to a specific page e.g. 1 and have there listed the private keys from #0 to #19 because they show 20 (the actual number is probably different) keys per page. If you pick the 3rd key from the top of page 42 you have the private key that is representing the number 20*42+3 = 843. Private keys are just that, numbers. Your chance to find a used private key while browsing that page is very low. The keys on the first few pages are the exception because some people thought it was a smart idea to use the private key #1 or #8 or #13 or #17 or #42 or #666 or any other number humans tend to apply higher meaning to.
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Its real, but you dont have to worry about it. They dont have a database with all keys (there is not enough storage space on the planet for that), they just generate them on the fly.
The chance is extremely low, you better worry how to keep your paper wallet safe & secure.
If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
So if two people have the same private key, they have the same wallet??If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
No, wallet is the software that handles the private keys for you.
Or for what do they use private keys than?
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Its real, but you dont have to worry about it. They dont have a database with all keys (there is not enough storage space on the planet for that), they just generate them on the fly.
The chance is extremely low, you better worry how to keep your paper wallet safe & secure.
If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
So if two people have the same private key, they have the same wallet??If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
No, wallet is the software that handles the private keys for you.
So you bought this account just recently?
...
Onkel Paul
...
Onkel Paul
No, its my account. I know about bitcoin for 3 years....
but never read / think before about this possible problem.
I was basically kidding you :-)
(although a bought account seemed like a remote possibility, too)
The info posted by Muhammed Zakir is pretty extensive and should answer all the concerns around "possibilities".
One thing that must be understood about low probabilities is that astronomically low probabilities (for example, for private key collisions) are for all practical purposes equal to "can't happen", but mathematically they are still not zero. This often confuses people who never deal with really large numbers.
Onkel Paul
So you bought this account just recently?
No way you could have been a bitcointalk member for 2 years without ever reading this frequently (asked/answered) question.
No way you could have been a bitcointalk member for 2 years without ever reading this frequently (asked/answered) question.
I have been on the forum a long time, have seen this brought up frequently. I KNOW the standard answer is "extremely unlikely". It doesn't mean I am convinced by this standard answer. "Extremely unlikely" doesn't bring much sense of safety to be honest.
I understand why OP is suddenly worried after 2 years of using bitcoin. Because 2 years is about the time when he accumulates enough bitcoin to be worried about loosing it.
So is it his website real or just fake?
Do we have to worry about is?
Do we have to worry about is?
It's fake. I have read from somewhere that the site only calculates the address from keys when someone click on the link.
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Yes, this site is real.
Do we have to worry?
maybe yes, maybe no
You have acces only to ballance in that address, not all bitcoins
from addresses placed in same wallet
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Yes, this site is real.
Do we have to worry?
maybe yes, maybe no
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
Yes, this site is real.
Do we have to worry?
maybe yes, maybe no
Given your example of 1 billion users at 10 addresses each:
There are 2^160 or about 1,460,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 possible addresses
In your scenario, 1,000,000,000 people are using 10 addresses each for a total of 10,000,000,000 possible addresses
10,000,000,000 / 2^160 should yield the probability of a collision occurring
10,000,000,000 / 2^160 = 0.00000000000000000000000000000000000000684
So the chances of a collision occurring in your scenario are approximately 0.000000000000000000000000000000000000684%
See why we don't consider collisions an issue?
There are 2^160 or about 1,460,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 possible addresses
In your scenario, 1,000,000,000 people are using 10 addresses each for a total of 10,000,000,000 possible addresses
10,000,000,000 / 2^160 should yield the probability of a collision occurring
10,000,000,000 / 2^160 = 0.00000000000000000000000000000000000000684
So the chances of a collision occurring in your scenario are approximately 0.000000000000000000000000000000000000684%
See why we don't consider collisions an issue?
The probability of a collision is found by a standard formula: p = 1 - k! / Nk-1(N-k)!, where k is the number of hashes generated (100x1010x103) and N is the number of possible hashes (2160).
This is a difficult number to calculate, but there is a good approximation: p = 1 - e-k(k-1)/2N
But even that value is difficult to compute because of the precision needed. Here is another approximation p = k2/2N.
So the answer is that the probability of at least one collision is approximately 7x10-19 or 0.00000000000000007%
See: http://preshing.com/20110504/hash-collision-probabilities
This is a difficult number to calculate, but there is a good approximation: p = 1 - e-k(k-1)/2N
But even that value is difficult to compute because of the precision needed. Here is another approximation p = k2/2N.
So the answer is that the probability of at least one collision is approximately 7x10-19 or 0.00000000000000007%
See: http://preshing.com/20110504/hash-collision-probabilities
Ok, new data, will recalc everything:
is my math roughly correct now?
If so, I can say: "Finding a collision is about as likely as being struck by lightning while taking a crap every year for 17 years in a row".
- probability of getting struck by lightning in any given year: 1/280000.
- probability of taking a shit at any given point in time: 1/(60*24) = 1/1440 (assuming you take a crap every day and the actual process takes 1 minute)
- probability of getting struck by lightning while taking a crap in any given year: 1/(280000*1440) = 1/1.47E11 = 2.48E-9
- probability of taking a crap while being in a situation where being struck by lightning can actually occur = 1/1440 = 0.25 = 1.74E-4
- probability of finding a collision: 1E-65
- getting hit by lightning while taking a crap for how many years in a row is equally probable as finding a collision: log(1E-65) / log(1.74E-4) = 17.3
is my math roughly correct now?
If so, I can say: "Finding a collision is about as likely as being struck by lightning while taking a crap every year for 17 years in a row".
-snip-
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
There is nothing to be scared of. Lucky guy get others' money. Isn't it cool?
Muhammed thank you for all this info =)
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
So is it his website real or just fake? but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
Do we have to worry about is?
So you bought this account just recently?
No way you could have been a bitcointalk member for 2 years without ever reading this frequently (asked/answered) question.
The risk is non-zero, but small enough that you don't need to bother (unless you're using software with a broken random number generator). If you bother about duplicate private keys, you should bother more about the possibility of being eaten alive by an ice bear or drowning in a soup bowl - both events are much more likely.
Onkel Paul
No way you could have been a bitcointalk member for 2 years without ever reading this frequently (asked/answered) question.
The risk is non-zero, but small enough that you don't need to bother (unless you're using software with a broken random number generator). If you bother about duplicate private keys, you should bother more about the possibility of being eaten alive by an ice bear or drowning in a soup bowl - both events are much more likely.
Onkel Paul
No, its my account. I know about bitcoin for 3 years....
but never read / think before about this possible problem.
Someone already create www.directory.io
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
but I think this site is only prank
Its good that guy who make this site didnt
implement address search option
The chance is extremely low, you better worry how to keep your paper wallet safe & secure.
If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
So if two people have the same private key, they have the same wallet?? If you worry about it, split your bitcoin to multiple addresses or using multi-signature address
hero member
Activity: 560
Merit: 509
I prefer Zakir over Muhammed when mentioning me!
Given your example of 1 billion users at 10 addresses each:
There are 2^160 or about 1,460,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 possible addresses
In your scenario, 1,000,000,000 people are using 10 addresses each for a total of 10,000,000,000 possible addresses
10,000,000,000 / 2^160 should yield the probability of a collision occurring
10,000,000,000 / 2^160 = 0.00000000000000000000000000000000000000684
So the chances of a collision occurring in your scenario are approximately 0.000000000000000000000000000000000000684%
See why we don't consider collisions an issue?
There are 2^160 or about 1,460,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 possible addresses
In your scenario, 1,000,000,000 people are using 10 addresses each for a total of 10,000,000,000 possible addresses
10,000,000,000 / 2^160 should yield the probability of a collision occurring
10,000,000,000 / 2^160 = 0.00000000000000000000000000000000000000684
So the chances of a collision occurring in your scenario are approximately 0.000000000000000000000000000000000000684%
See why we don't consider collisions an issue?
The probability of a collision is found by a standard formula: p = 1 - k! / Nk-1(N-k)!, where k is the number of hashes generated (100x1010x103) and N is the number of possible hashes (2160).
This is a difficult number to calculate, but there is a good approximation: p = 1 - e-k(k-1)/2N
But even that value is difficult to compute because of the precision needed. Here is another approximation p = k2/2N.
So the answer is that the probability of at least one collision is approximately 7x10-19 or 0.00000000000000007%
See: http://preshing.com/20110504/hash-collision-probabilities
This is a difficult number to calculate, but there is a good approximation: p = 1 - e-k(k-1)/2N
But even that value is difficult to compute because of the precision needed. Here is another approximation p = k2/2N.
So the answer is that the probability of at least one collision is approximately 7x10-19 or 0.00000000000000007%
See: http://preshing.com/20110504/hash-collision-probabilities
Ok, new data, will recalc everything:
is my math roughly correct now?
If so, I can say: "Finding a collision is about as likely as being struck by lightning while taking a crap every year for 17 years in a row".
- probability of getting struck by lightning in any given year: 1/280000.
- probability of taking a shit at any given point in time: 1/(60*24) = 1/1440 (assuming you take a crap every day and the actual process takes 1 minute)
- probability of getting struck by lightning while taking a crap in any given year: 1/(280000*1440) = 1/1.47E11 = 2.48E-9
- probability of taking a crap while being in a situation where being struck by lightning can actually occur = 1/1440 = 0.25 = 1.74E-4
- probability of finding a collision: 1E-65
- getting hit by lightning while taking a crap for how many years in a row is equally probable as finding a collision: log(1E-65) / log(1.74E-4) = 17.3
is my math roughly correct now?
If so, I can say: "Finding a collision is about as likely as being struck by lightning while taking a crap every year for 17 years in a row".
-snip-
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
What you people think about that? This can become a big problem
for Bitcoin in the future... no?
I am a little scared
There is nothing to be scared of. Lucky guy get others' money. Isn't it cool?
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