Still I don't see that making the conference more attractive.

Go to the xyz Bitcoin conference and have a good time vs go to the Russian Bitcoin Conference and possibly end up arrested.

We have yet to see that.  We have yet to even see payment processors offer that as an option.  Given the near instant liquidity between BTC and copy cats a merchant is very unlikely to lose sales by not offering to accept payments in 928,390,238,120 different alt coins.  So the payment process gains a negligible amount in incremental sales.

There are also the logistical issues.  Services like bitpay lock an exchange rate in order to guarantee the merchant a certain amount in USD (or other currency).  BitPay takes the currency rate risk, you can only move/transfer risk not erase it.   Imagine what would happen if someone tried to buy $1,000,000 worth of mining rigs through a merchant using BitPay and decided to pay with say PeerCoin or FeatherCoin or TerraCoin or <insert flavor of week here>.  What would a $1,000,000 sell do to the market?

Could it happen?  Maybe.  However there is very little value and a huge amount of risk for the payment processor.  

Sure.  However most likely it is buy shares on exchange, turns out to be scam. You have bought nothing but air, have no legal right, and lose all your money.

Sellers of said shares (and the exchanges) may be violating US law but the buyer isn't breaking the law.  Still that is little comfort when you lose everything.  "Hooray all my bitcoins are gone but I didn't break the law".

I never said it isn't.  Please read what I wrote.  Eventually the pool of unspent outputs which are valid on both forks will aproach zero.

I must have taken it off some time ago for one reason or another.  Always good to reverify ones assumptions by experimentation.  In this case the experiment validated the hypothesis.  Also knowing Angry Mint this will likely span countless posts of baseless assumptions and blatantly incorrect technical details so I think it is back to ignore.  Life is too short, and you can't fix stupid.

Wait isn't the same thing as reject.  If miner waits until the next block then one of the tx will be confirmed.  Still there is no reason for a miner to wait on a paying tx.  Once again theoretical nonsense, based on a presumption that miners are idiots and will do dumb things you need them to.


Economics dictate miners won't be stupid.  If they are they will go bankrupt and be replaced by ones less stupid.


You say "send" and "propagation" as if they are different events.  How do you think the merchant LEARNS of the payment.  That is right it is propogated through the network.

So the merchants tx propagates rapidly within seconds, but magically the attackers tx only propagates to nodes that aren't linked to the merchant although the attacker has no way of knowing which ones those are.

Gotcha.

How can you get this wrong after being here so long.

1) The network will never reject BOTH transactions.  If the transactions are valid one will be confirmed.

2) To be included in the next block the attacker's tx will need to win the "race" of course if the merchant sees the attack tx it becomes very obvious that a double spend is being attempted and the sale can be halted.

Merchants (or their processors) can improve the odds by using listening nodes which communicate out of band width the merchants (or processor's wallet).  If a merchant had 8 geo located listening nodes with an average of 2,000 peers each that would be 16,000 peers.  Now if any one of those 16,000 peers are relayed the double spend the merchant will be aware of this.  The merchant can nearly instantly detect attempts to double spend.  The merchant can delay the sale by a few seconds to ensure good propagation and see if there are any double spends.

If the attacker waits until after the sale is complete, the entire network will already be aware of the merchant's tx and reject the attacker's as a double spend.
If the attacker sends both tx simultaneously within seconds some node connected to the merchants listening network will see it and a "DOUBLE SPEND. ASK FOR ALTERNATE PAYMENT" can be displayed to the cashier.

This type of detection would not be able to see Finney attacks however 0-confirm isn't suitable for all transactions and there are significant costs and complicates with pulling off a Finney attack in all situations.

It doesn't matter a given transaction over time will only be valid on one fork or another.

For example the coins from the first block after the fork would only be valid on the fixed reward fork.  Nodes on the the original fork would see it as invalid.

This also means any spend which uses those coins would also only be seen as valid on one fork.   Since the input of any tx is the output of prior tx it also invalidated all subsequent tx which use the change from that transaction.

While at day 0 most tx will be valid on both halves of the fork, like a metaphorical fork in the road, the two chains will diverage over time and eventually the vast majority of transactions will only be valid on a single fork.

This.  Sure anyone can make a new client which changes the Bitcoin protocol.  One way of looking at it is that altcoins are an example of this.   However nothing can force existing users to adopt the new "changed" client.   As long as they don't, their existing clients will reject blocks and transactions which violate their rules.

Anyone can fork Bitcoin, nobody can fork force you to use that fork.

MtGox left the door "open" when their nodes started writing garbage non-compliant transactions.  Prior to v0.8 most of MtGox garbage tx were still relayed by other nodes.  With prompt relaying it becomes very difficulty to modify the tx and then win a race.  As the number of v0.8+ nodes started increasing, transactions created by MtGox started having a harder and harder time propogating the network.

Like a critical cascading failure this flaw exposed other flaws in MtGox "GOX SPECIAL v0" client they hacked together without basic knowledge of the protocol.  Their client would attempt to create tx without sufficient tx fees (despite charging users 10x the min mandatory fee). Their client would attempt to spend immature newly mined coins.  Rather than fix issues they simply modified the client to spend older and larger "coins" first.

This really came to a critical level in the last 30 days when the percentage of legit withdraws became massive.  By now most of the network was v0.8+ so they were just dropping MtGox tx, the need to continually recreate withdraws over and over not only provided the attacker with "cover", it also exhausted their pool of old, large coins, exposing the the other issues with insufficient fees and spending immature coins. The flaws in their design compounded upon each other to create this massive (at one point >2,800 tx and anecdotally more than 50% failure rate) backlog of broken withdraws.

My guess is someone figured out they could take the garbage tx non-compliant tx, clean it up and get paid faster.  From there it was only a small leap in logic to "wait a second, MtGox servers still show the old tx hash.  I bet I could tell them I haven't been paid and blend right in with the thousands upon thousands of legit reports of broken transactions". 

Of course if the ONLY problems MTGox had were non-canonical signature, spending immature coins, double spending their own payments (race condition?), and paying insufficient fees the attacker STILL couldn't have stolen funds.  Like I said this just opened the door.  That combined with relying on tx ids and resending payments without investigation after a report on non-payment is what made the attack profitable.

Margins on mining are low (possibly negative), you have absolutely no pricing power, brands are worthless (a hash is a hash regardless of who makes it), and your profitability is largely determined by what other people (not you) do.   Does that sound like a business model that Google would be interested in?

I would find it much more likely that a Google would attempt to buy a company like BitPay then get involved in mining.

I expect someone to eventually pull off a Sybill attack against a poorly connected merchant node.  There is no guaranteed defense but you increase your resistance by using multiple listening nodes.  Then again maybe I am just crypto-paranoid.

People who believe MtGox gave most of their bitcoins to the attackers and are now insolvent.  If that is true (and I am not saying it is) then they may believe holding dollar "debt" in an insolvent Japanese company is better than holding bitcoins as AFAIK there have been court cases in Japan regarding the standing of bitcoins in a situation like this.  If you believe MtGox is insolvent, being owed USD "may" be safer than being owed BTC.  If enough people believe that sell BTC to hold dollars then you would see the price distort as it has.

Simple Version:
The exchange rate on MtGox may no longer represent the value of a bitcoin, but instead reflect the relative value of a MTGox IOU for USD vs a MtGox IOUT for BTC.

The statement by the administration is a bunch of legal nothing.

Summarized.  "We won't prosecute you, but it is still illegal and at any point in the future for any reason we could suddenly and without warning decide to prosecute you.  Also there is no legal defense or safe harbor on actions you take now even if you decide to suspend them in the future if/when our policy changes."

How likely do you think banks (and companies like BitPay) will see this as the legal clarity they need to move forward?

Can't help you if you dial the wrong phone number.   The phone number on the website has never been disconnected or busy.  The site offers secure (SSL protected) chat for customers so if you have specific questions the fastest response is to create an account and click on help at the bottom of any page.

Yeah that is like saying "Keep toasters exactly like they work now except they also solve cancer".

The later.  MtGox doubled paid attackers for who knows how many times and this has could have been going on for a month.  How many Bitcoins does MtGox owe customers?  How many do they have?

Learn what mining actually does, why it is needed, and how the current solution works without centralized control.

Once you do that it is obvious why your idea makes no more sense than designing a toaster which also cures cancer and paints your house.

I just saw zapwallet.  Nice solution.  Kill all tx records and then rescan to pickup only the confirmed ones. Smart.

Why do people still buy preorder rigs from BFL?