pgp user trying to figure out bitcoin

[tdexxx]

I think I have a simple question.  My bitcoin client seems to be able to create bitcoin addresses.  Do those addresses my client creates correspond to addresses on the blockchain, or do they only exist on my computer?  And if my own addresses do correspond with addresses on the blockchain, how does the blockchain "know" when my bitcoin client creates an address?

Tom

[BurtW]

When you create an address on a client it only exists on the client.  You can create as many addresses as you want.

When the transactions to or from that address happen then the transactions all go into the block chain.

So, if you want to see your address in the block chain then you must send some BTC to that address.

[tdexxx]

When the transactions to or from that address happen then the transactions all go into the block chain.

Thanks for replying.  So you're saying that the addresses created by the bitcoin client don't exist on the blockchain until come coins are transferred from that address, and once coins are transferred the sending address will exist on the blockchain in addition to being on the client?  Does that address stay on the blockchain from then on?  Is there some mechanism that prevents two different clients from coincidentally making the same address?

[Kluge]

When the transactions to or from that address happen then the transactions all go into the block chain.

Thanks for replying.  So you're saying that the addresses created by the bitcoin client don't exist on the blockchain until come coins are transferred from that address, and once coins are transferred the sending address will exist on the blockchain in addition to being on the client?  Does that address stay on the blockchain from then on?  Is there some mechanism that prevents two different clients from coincidentally making the same address?

Right. The client gives "the blockchain" the public key when it's used, and that key is always out there from then on. There is no pruning in the full blockchain, but the number of people using full blockchains is decreasing as new pruning methods are introduced to the different clients (this is a moot point, though, given there are public, searchable, online blockchain copies). There are no mechanisms to prevent clients from making the same address. It's practically impossible to generate a specific address, but it is much more possible to discover already-used addresses when generating indiscriminately. There are programs out which generate enormous chunks of addresses, and check them against the blockchain to see if they've been used. If there's a match, the private key is added to a log. AFAIK, they have not yet been successful at stealing anything. You should generally not re-use addresses for significant amounts of coins because of this on top of a couple other reasons.

[cp1]

All addresses "exist", they're just not used.  Possible addresses are numbered up to 2^160.  There's no use thinking if an address exists or not, it's just a number.  If someone "sends" bitcoins to that address they can only be spent by someone who knows the private key.  The only thing that keeps a client from generating the same address that someone else is using is pure chance.

[cp1]

In fact, if your client generated an address that was already in use it should make a cha-ching sound instead of rejecting it.

[Gabi]

+1 what cp1 said

[BurtW]

It must be noted that the probability of generating the same address as someone else is so low that it is "impossible".  There are dozens of threads related to this issue.  It is not something that I worry about, that is for sure.

[BurtW]

Is PGP a currency?

No it is used to sign and encrypt messages

PGP uses RSA or other types of public/private keypairs
Bitcoin uses ECC public/private keypairs

So I think by "PGP user" the OP meant "I do know a bit about keys, keypairs, etc. so I am not a total noob"

[BurtW]

someone please explain pgp thanks

Ever heard of this new fangled thing called "Google"?

https://en.wikipedia.org/wiki/Pretty_Good_Privacy

BTW:   It was created by Phil Zimmermann in 1991, he lived in Boulder, I lived in Boulder, we met and I got a copy of one of the first versions on a floppy directly from the man himself!

That make me famous, right?

[canuck]

It must be noted that the probability of generating the same address as someone else is so low that it is "impossible".  There are dozens of threads related to this issue.  It is not something that I worry about, that is for sure.

Despite your use of the "i" word, this is still something of an understatement simply because it's just not dramatic enough. 

I like to think of using all of the sun's energy to generate addresses.  If you had a computer powered by the Sun, generating millions of addresses per second, statistically, the Sun would burn out before you generated an address used by some one else.

[cp1]

I like to think of using all of the sun's energy to generate addresses.  If you had a computer powered by the Sun, generating millions of addresses per second, statistically, the Sun would burn out before you generated an address used by some one else.

I can generate millions of addresses per second with my video card.  Well like 8 million.  It says it'll only take 10 years to find 1FAGABEEFE*

Apparently it'll take 10^48 years to find Avalon's address.  I better get started.

[Kluge]

I like to think of using all of the sun's energy to generate addresses.  If you had a computer powered by the Sun, generating millions of addresses per second, statistically, the Sun would burn out before you generated an address used by some one else.

I can generate millions of addresses per second with my video card.  Well like 8 million.  It says it'll only take 10 years to find 1FAGABEEFE*

Apparently it'll take 10^48 years to find Avalon's address.  I better get started.

I think of it like this:
You're about as likely to find Avalon's address in use as if Avalon stored their cash in a wallet buried in a landfill. By giving the public key, we know what the wallet looks like, but this is not very helpful. But - what are the odds of finding *a* wallet in any landfill with coins in it if we have highly-efficient garbage-sorting robots?

Let's say there are 500,000 wallets in landfills containing money. Let's say there are 100 "treasure hunters" with four garbage-sorting robots each, each sorting through 8m objects per second. In total, the treasure hunters are able to sort through a total of 3.2b objects per second out of a total of 2^160 objects. We know there are roughly 500k wallets in existence, effectively the wallet pool when trying to find *a* money-filled wallet to 2.92e+42 in our example, or 292,000,000,000,000,000,000,000,000,000,000,000,000,000 (+- a couple zeroes!), so our chance of finding a wallet-filled address at any second is 3,200,000,000/292,000,000,000,000,000,000,000,000,000,000,000,000,000, or ~1.095e-33(%).

Hooboy these numbers suck. Let's try monthly percentage. %/sec*60(to get to /min)*60(to get to /hr)*24(to get to /day)*30(to get to /month) = ~2.838e-27(%) or..... .000000000000000000000002838%/month (+- a couple zeroes, again).

Let's change our example up, though -- just for fun. Let's say miners have decided it might be worth more to start these kinds of "treasure hunting" pools once GPU-mining kicks the bucket for BTC. It gets REALLY popular, and there are now the equivalent of 10,000 treasure hunters with four 8m/sec garbage-sorting robots each. Bitcoin gets more popular, too, and there are currently 25,000,000 money-filled wallets in landfills.

(2.92e+42)/25,000,000=5.8460065493236116728147393308651e+40 (effective "landfill pool" [address pool] after factoring in # of cash-holding wallets)
5.8460065493236116728147393308651e+40/320000000000=5.4738221262688166832958186847263e-30 (%chance of pool finding address per second)
5.4738221262688166832958186847263e-30*60*60*24*30=1.4188146951288772843102762030811e-23 (%chance of pool finding address per month)

or..... ~.00000000000000000001419% (+- one zero),  0.00000000000000000017028%/year, 0.000000000000000008514%/50years, 0.000000000000008514%/500kyears

.... And all that math (none of which I'm sure of!) just goes to show..... shit's probably pretty safe... until dedicated ASIC address generators hit the market at 1/1,000 the price of what it'd currently cost to do the same work. Then it may only take a few billion years. 


(someone should correct my math)

[acne]

pgp is a big difference from Bitcoin, I wish you the best in figuring it out