Bitcoin Forum
December 15, 2024, 01:50:20 AM *
News: Latest Bitcoin Core release: 28.0 [Torrent]
 
   Home   Help Search Login Register More  
Pages: [1] 2 »  All
  Print  
Author Topic: Can you prove you sent someone a bitcoin?  (Read 2715 times)
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 01, 2011, 08:38:35 PM
 #1

Hi all, just a basic question really.... is it possible to prove that A sent X BTC to B?
Thanks Smiley
FooDSt4mP
Full Member
***
Offline Offline

Activity: 182
Merit: 100


View Profile
July 01, 2011, 08:40:21 PM
 #2

Blockexplorer.com

As we slide down the banister of life, this is just another splinter in our ass.
kokjo
Legendary
*
Offline Offline

Activity: 1050
Merit: 1000

You are WRONG!


View Profile
July 01, 2011, 08:40:50 PM
 #3

http://blockexplorer.com/

"The whole problem with the world is that fools and fanatics are always so certain of themselves and wiser people so full of doubts." -Bertrand Russell
error
Hero Member
*****
Offline Offline

Activity: 588
Merit: 500



View Profile
July 01, 2011, 08:41:44 PM
 #4

You can prove you sent bitcoins to an address by spending the change. You cannot prove who received the bitcoins without their cooperation.

3KzNGwzRZ6SimWuFAgh4TnXzHpruHMZmV8
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 01, 2011, 08:42:34 PM
 #5

You can prove you sent bitcoins to an address by spending the change. You cannot prove who received the bitcoins without their cooperation.
Hi, Can you explain more please? Thanks! Smiley
bitlotto
Hero Member
*****
Offline Offline

Activity: 672
Merit: 500


BitLotto - best odds + best payouts + cheat-proof


View Profile WWW
July 01, 2011, 08:43:23 PM
 #6

Not really. Unless:
-all your money is in one address in one wallet
-you announce you will send another amount to another address of yours and then do (has to be a pretty unique amount)
-but even then, someone else could see the announcement and send it again
-all that would prove is the from address is the same and was sent again after you announced

*Next Draw Feb 1*  BitLotto: monthly raffle (0.25 BTC per ticket) Completely transparent and impossible to manipulate who wins. TOR
TOR2WEB
Donations to: 1JQdiQsjhV2uJ4Y8HFtdqteJsZhv835a8J are appreciated.
error
Hero Member
*****
Offline Offline

Activity: 588
Merit: 500



View Profile
July 01, 2011, 08:43:39 PM
 #7

You can prove you sent bitcoins to an address by spending the change. You cannot prove who received the bitcoins without their cooperation.
Hi, Can you explain more please? Thanks! Smiley

Which part do you want to have explained?

3KzNGwzRZ6SimWuFAgh4TnXzHpruHMZmV8
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 01, 2011, 08:44:31 PM
 #8

You can prove you sent bitcoins to an address by spending the change. You cannot prove who received the bitcoins without their cooperation.
Hi, Can you explain more please? Thanks! Smiley

Which part do you want to have explained?
The "change" part... and how I find it and spend it. Smiley
John Tobey
Hero Member
*****
Offline Offline

Activity: 481
Merit: 529



View Profile WWW
July 01, 2011, 08:46:30 PM
 #9

You could come pretty close, but the software support is rather lacking.  With a patched client, you can sign a message with the key pair used in the transaction.  The message could say "Jack owns this coin".  That would be pretty good evidence, though there is always the chance the real owners gave you the key pair after they spent the coin, or you paid them to sign a false message.

If you haven't yet sent it, you could in theory create a transaction and send its hash to the recipient before you execute it.  Again, the current software doesn't help much here, but with the command line you can at least find the transaction hash after the fact.  The recipient could check the hash in a database like Block Explorer.

Can a change to the best-chain criteria protect against 51% to 90+% attacks without a hard fork?
error
Hero Member
*****
Offline Offline

Activity: 588
Merit: 500



View Profile
July 01, 2011, 08:48:00 PM
 #10

You can prove you sent bitcoins to an address by spending the change. You cannot prove who received the bitcoins without their cooperation.
Hi, Can you explain more please? Thanks! Smiley

Which part do you want to have explained?
The "change" part... and how I find it and spend it. Smiley

Send somebody some money. View your transaction in Block Explorer. You will see that your money went to your recipient, AND some more money went to another address. That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.

3KzNGwzRZ6SimWuFAgh4TnXzHpruHMZmV8
John Tobey
Hero Member
*****
Offline Offline

Activity: 481
Merit: 529



View Profile WWW
July 01, 2011, 09:05:58 PM
 #11

Send somebody some money. View your transaction in Block Explorer. You will see that your money went to your recipient, AND some more money went to another address. That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.

True... if you have not already spent it and its descendants... and if the transaction did not happen to come out even (without change).

I think in the future transaction creation will be separate from execution, and sending the transaction hash first will be the straightforward solution in cases where you know beforehand that you will need proof.

Can a change to the best-chain criteria protect against 51% to 90+% attacks without a hard fork?
Stephen Gornick
Legendary
*
Offline Offline

Activity: 2506
Merit: 1010


View Profile
July 01, 2011, 09:07:59 PM
 #12

Hi all, just a basic question really.... is it possible to prove that A sent X BTC to B?

Related:
  - http://forum.bitcoin.org/index.php?topic=4411.0

Unichange.me

            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █
            █


jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 01, 2011, 09:27:49 PM
 #13

Send somebody some money. View your transaction in Block Explorer. You will see that your money went to your recipient, AND some more money went to another address. That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.
Thanks! Just out of interest, how long does it take for a transaction to appear in BlockExplorer? Smiley
kokjo
Legendary
*
Offline Offline

Activity: 1050
Merit: 1000

You are WRONG!


View Profile
July 01, 2011, 09:38:49 PM
 #14

Send somebody some money. View your transaction in Block Explorer. You will see that your money went to your recipient, AND some more money went to another address. That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.
Thanks! Just out of interest, how long does it take for a transaction to appear in BlockExplorer? Smiley
it appears when it confirmed, and included in a block.

"The whole problem with the world is that fools and fanatics are always so certain of themselves and wiser people so full of doubts." -Bertrand Russell
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 01, 2011, 10:06:28 PM
 #15

Send somebody some money. View your transaction in Block Explorer. You will see that your money went to your recipient, AND some more money went to another address. That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.
How do I spend that particular coin?
koin
Legendary
*
Offline Offline

Activity: 873
Merit: 1000


View Profile
July 01, 2011, 11:03:43 PM
 #16

That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.
How do I spend that particular coin?

how do you spend your change?  the ability to spend the change never left your wallet, so you can just spend using the bitcoin client as normal.
oh, i hadn't read back to see what you are trying to do.

the bitcoin client chooses for you which coins to use in spending.  there is a patch that you can use to help though: http://forum.bitcoin.org/index.php?topic=23354.0
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 02, 2011, 12:55:40 PM
 #17

That is the change, and it returns to your wallet at a newly generated address. You merely need to spend that particular coin.
How do I spend that particular coin?

how do you spend your change?  the ability to spend the change never left your wallet, so you can just spend using the bitcoin client as normal.
oh, i hadn't read back to see what you are trying to do.

the bitcoin client chooses for you which coins to use in spending.  there is a patch that you can use to help though: http://forum.bitcoin.org/index.php?topic=23354.0

Thanks for that, although I sent the payment using a web-based client (mybitcoin.com) and would this therefore not work in my case?
bitlotto
Hero Member
*****
Offline Offline

Activity: 672
Merit: 500


BitLotto - best odds + best payouts + cheat-proof


View Profile WWW
July 02, 2011, 02:39:09 PM
 #18

Thanks for that, although I sent the payment using a web-based client (mybitcoin.com) and would this therefore not work in my case?
That's correct. You would have to have access to mybitcoin's logs as well.

*Next Draw Feb 1*  BitLotto: monthly raffle (0.25 BTC per ticket) Completely transparent and impossible to manipulate who wins. TOR
TOR2WEB
Donations to: 1JQdiQsjhV2uJ4Y8HFtdqteJsZhv835a8J are appreciated.
FreeMoney
Legendary
*
Offline Offline

Activity: 1246
Merit: 1016


Strength in numbers


View Profile WWW
July 02, 2011, 06:04:40 PM
 #19

Someone being able to spend the change is not sure proof of sending the original tx. What you read as change could be another payment made simultaneously using SendMany. You need to see the person use the IN address again.

None of that is needed just to show that the tx happened though, just look in block explorer.

Play Bitcoin Poker at sealswithclubs.eu. We're active and open to everyone.
jack102938 (OP)
Full Member
***
Offline Offline

Activity: 141
Merit: 100



View Profile
July 02, 2011, 06:52:39 PM
 #20

Another really n00b question, apologies... can someone explain to me how to read BlockExplorer.com... like which addresses mean what? For example, on http://www.bitlotto.com it says you can send a payment (the winnings) back to the person who sent the winning ticket bitcoin... so I assume another address is created which is associated with the sender of bitcoins? so confusing Sad
Pages: [1] 2 »  All
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!