<p>The failed transaction won't get stored in a block on the blockchain, so it will be hard for an average person to find them.  I think most of the Bitcoin nodes will delete them from memory eventually.</p>

<p>Also, these sneaky undo transactions are probably not broadcast so publicly in the same way that normal transactions are; they are probably sent to a smaller network of miners who want to participate in this undo system.</p>

CC BY-SA 3.0
2014-05-25T00:17:17.443Z
But isn't it rather counter-intuitive? I mean for it to be undoed successfully it needs to be broadcasted to the *public* network right? Or is it such that this small pools of private networks actually have a non-insignificant chance of getting their transactions to win?
Pacerier
CC BY-SA 3.0
2014-05-25T02:56:40.173Z
Even if that's the case, it would be inaccurate to say that "nobody will be able to see it". The miners in question would see it.
Nate Eldredge
CC BY-SA 3.0
2014-05-25T06:57:51.347Z
Nate, actually, the BitUndo system doesn't have to distribute the actual undo transactions to the miners immediately, it can just distribute hashes of transactions.  Then when the miner succeeds in finding the block, they would have to query Bitundo and prove they have a block and ask Bitundo to fill in all the undo transactions in that block.  From my reading of http://www.bitundo.com/developer.html , it appears they are not doing it this way, but I think they could.
David Grayson
CC BY-SA 3.0
2014-05-25T07:04:06.367Z
Actually, only the public ones are available on the websocket server; I don't know how the private ones actually work but maybe it's something like I suggested in the last comment.
David Grayson
CC BY-SA 3.0
2014-05-25T07:16:48.103Z
@DavidGrayson, But that seems theoretical... I mean practically speaking most miners don't do that right?
Pacerier
CC BY-SA 3.0
2014-05-24T23:17:49.070Z
2014-05-24T23:17:49.070Z
David Grayson
<p><a href="http://www.bitundo.com/undo/index.html#/proceed" rel="nofollow">BitUndo private transactions</a>:</p>

<blockquote>
  <p>If you choose to make your undo transaction private, <strong>nobody will be
  able to see that you tried to undo a transaction, unless it succeed</strong>.
  You have to know that a private undo transaction has less chances to
  succeed, as is not distributed in the whole bitcoin network.</p>
</blockquote>

<p>From what I know, for a undo transaction to even stand a chance of competing with the main transaction, it has to be broadcasted to the <em>public</em> network.</p>

<p>If so, then how does Bitundo "private transactions" work?</p>

<transactions><blockchain>
How can "undo" bitcoin transactions be "private"?
Pacerier
# How can "undo" bitcoin transactions be "private"?

(Asked by: username_0 on 2014-05-24)

[BitUndo private transactions](http://www.bitundo.com/undo/index.html#/proceed):

> If you choose to make your undo transaction private, **nobody will be
> able to see that you tried to undo a transaction, unless it succeed**.
> You have to know that a private undo transaction has less chances to
> succeed, as is not distributed in the whole bitcoin network.

From what I know, for a undo transaction to even stand a chance of competing with the main transaction, it has to be broadcasted to the *public* network.

If so, then how does Bitundo "private transactions" work?

**Tags:** transactions, blockchain


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## 1 answers

### Answer by username_1 on 2014-05-24. Score: 2

The failed transaction won't get stored in a block on the blockchain, so it will be hard for an average person to find them. I think most of the Bitcoin nodes will delete them from memory eventually.

Also, these sneaky undo transactions are probably not broadcast so publicly in the same way that normal transactions are; they are probably sent to a smaller network of miners who want to participate in this undo system.

> **Comments:**
> **username_0**: But isn't it rather counter-intuitive? I mean for it to be undoed successfully it needs to be broadcasted to the *public* network right? Or is it such that this small pools of private networks actually have a non-insignificant chance of getting their transactions to win?  
> **username_2**: Even if that's the case, it would be inaccurate to say that "nobody will be able to see it". The miners in question would see it.  
> **username_1**: username_2, actually, the BitUndo system doesn't have to distribute the actual undo transactions to the miners immediately, it can just distribute hashes of transactions.  Then when the miner succeeds in finding the block, they would have to query Bitundo and prove they have a block and ask Bitundo to fill in all the undo transactions in that block.  From my reading of http://www.bitundo.com/developer.html , it appears they are not doing it this way, but I think they could.  
> **username_1**: Actually, only the public ones are available on the websocket server; I don't know how the private ones actually work but maybe it's something like I suggested in the last comment.  
> **username_0**: @username_1, But that seems theoretical... I mean practically speaking most miners don't do that right?  

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