But the client probably won't know about both transactions until there is a conflict where a block comes in with the conflicting information.  This is because invalid transactions don't get relayed and for any node, one of those two will be considered invalid.

The client would need to connect to an external listening service to know that a double spend attempt had occurred.  No such service exists.   Though TransactionRadar.com, http://blockchain.info/double-spends, and elsewhere are tools in the same space.

What exactly would that indicate (other than the level of hashing occurring)?

I would bet the best opportunity where this relates to Bitcoin would be in areas where remittance payments are commonly received and there also exists is a mobile phone where domestic person-to-person payments is done without huge fees.  Thus in a village, for example, there would be demand for one or more individuals who could perform exchange from Bitcoin to the local mobile currency and then make the payouts to the recipient via mobile.

Perhaps in Asia  as well -- like the Philippines and elsewhere?

I like those odds!

I did specify that following proper precautions (i.e., no incoming transactions being one of them) will protect the recipient.  Using the bitcoin.org client following the default mode is not a proper protection against someone trying to perform a race attack.

I'ld consider taking you up on your bet if you are using default configuration -- i.e., the client determines which 8 nodes you get connected to.  That will likely mean you are not directly connected to any pool (and are at least one hop from a pool).

Then I will make a transaction with a spend to myself and only broadcast that to the top four pools.  A few milliseconds later I will, from another node with a copy of the same wallet, announce the double spend to a well connected node that is not one of those four with the hope that the transaction will get relayed to a node you happen to be connected to.  It will then be a race -- will the original transaction from one of the four pools reach you first, or will your client see the double-spend transaction first?  I wouldn't be surprised if following these steps that your client will show the double spend and the original transaction is what gets mined at least 33% of the time. [Update: Since those four pools only account for about 66% of hashing strength, I dropped the number for the double-spend success percentage guess to 33%.]


Does the client do anything different now?  I thought the client, having a double-spend transaction, just stays at 0/unconfirmed forever.  Yes, you'll probably notice that the transaction isn't confirming tens of minutes later but it isn't like seconds after receiving the transaction you get a red popup with a warning.


What I was trying to point out is that a merchant accepting on 1-confirmation can be just as vulnerable to the finney attack as the 0-confirmation should proper precautions (i.e., not allow incoming transactions, be well connected) not be implemented.

So, maybe we can learn something here.  I'ld like to see the results of an experiment that determines, using the default configuration for the client on a typical consumer network connection (w/UPnP), how successful the race attack actually is.

For the attacker this can be done using just two node instances each with a copy of the same wallet.  (i.e., probably don't even need to go the extra step of having a script running on each of four nodes, to ensure the transaction gets announced simultaneously to the four large pools.)  

I wonder if the site being unavailable has anything to do with this announcement.
 - http://www.downforeveryoneorjustme.com/p2pfoundation.net

And that is why there's really no comparison between the two.


If there were a change in the law or somehow the use of bitcoin was declared to be illegal in certain parts of the world, there could be a fantastic drop in value.  Barring that, any move would be telegraphed in advance.  For instance here:
 - http://blockchain.info/charts/n-transactions

That is not an accurate statement.  Unless proper precautions are taken, a 0/unconfirmed race attack can be successful -- maybe 50% of the time even.
The precautions include configuring the client so that there are no incoming connections allowed and to explicitly have outgoing connections to the top miners.

I've actually been surprised that there haven't yet been reports of anyone in the marketplace forum or on the #bitcoin-otc marketplace losing their bitcoins received to a double spend race attack yet.  It takes really no technical skill -- just use the same wallet in two places and try to spend from the same coin to two different addresses.   Eventually one of those times the one seen by the recipient will differ from the one seen by the miner who eventually gets that block.


There is a variation of the Finney Attack that could defraud just as easily with a 1-confirmation as with a 0/unconfirmed though the same recommendation above (to allow no incoming) prevents that variation from becoming successful as well.
 - http://bitcointalk.org/index.php?topic=36788.msg463391#msg463391

In some municipalities even putting up a doghouse requires a permit.

I do look forward to seeing the first solar-based FPGA mining operation run out of a HexaYurt in the middle of the desert:
 - http://hexayurt.com/

Fixed that for you.

Options with an April expiry are still opened throughout April.  So how, by March 30th, is the amount of needs for April known?  Or is it an estimate, and then exposure only up to that amount already secured are then sold?

When did the "SMS Phone Deposits" feature get added?

 - https://blockchain.info/wallet/sms-phone-deposits

The service now uses ZenDesk rather than e-mail for support.  That's a good move.  e-mail sucks for support once you try to support more than a dozen customers.

 - https://getbitcoin.zendesk.com/

Site is not responding.  Any update?

BTCrow is offline.  Is this a server issue?

Heh, it stresses mining as the way to generate funds to invest.

I'm not sure I was comprehending correctly.  Did that say investors ("angels") give up 80% of any profits from ventures that launch because those profits are then reinvested into future ventures ("validated ideas")?  I had a hard time understanding the flow, as far as what an investor has control of.

When I'm choosing to invest in a startup, I'm hoping for a big hit.  I understand the risks but I'm thinking I'm smarter than everyone else and will discover the 10 bagger that nobody else did.  That supports my thinking that even if four-out-of-five investments fail, I still gain big thanks to the one that hits it big time.  But if I'm having to give up 80% of the gains, yet eat the losses then my motivation to go this route goes away.  I guess I am saying I don't trust that reinvesting of the profits in new "validated ideas" is always going to be the best use of my funds.

Janet Tavakoli ... apparently not a fan of the CROWDFUND Act:


 - http://www.youtube.com/watch?&v=wTWKT3pZgT8#t=1157s

To be fair, I think Tavakoli's argument is with the provisions of the JOBS act regarding what it will now allow for "emerging growth companies" (those with up to $1 billion in annual revenue) and she isn't specifically criticizing the CROWDFUND act (for companies raising up to $2 million through crowdfunding).

Nice reply after asking how an investor of a crowdfunded business can sell shares purchased after the 1 year statutory lockup period for IPO'd shares expires:

- http://www.quora.com/Crowdfunding/How-does-an-investor-of-a-crowdfunded-venture-sell-the-shares

Since Forex sites don't add BTC, it would be good for there to be a chart resource that fills in the gap.

For instance, BTC/XAU (Gold) historic chart, BTC/XAG silver and BTC/OIL even.

I have some of that data here:
 - https://docs.google.com/spreadsheet/ccc?key=0AmcTCtjBoRWUdHJuUE1mUkFxa3A0eHBDQkxZLVVFZmc

The data is from Wikiposit
 - http://wikiposit.org

This is kind of what I'm thinking ... for BTC as the base currency:
 - http://finviz.com/futures_charts.ashx?t=SOFTS&p=w1

There is a corresponding blog post by Stossel:
 - http://www.foxbusiness.com/on-air/stossel/blog/2012/03/01/stossel-dollars

And as far as the allegation that private currency is illegal, the U.S. Attorney's political commentary after the Nothaus trial does not a law make:
 - http://mises.org/daily/5184

Most coin dealers will sell coin flips individually -- cost is probably a quarter or so.
 - http://coins.about.com/od/coinsglossary/g/coin_flip.htm