Topic: Transactions Withholding Attack - page 11. (Read 27579 times)

Cartel doesn't need to get the transactions into the Bitcoin block chain asap, for the reason I explained in my prior post.


You appear to be ignoring the game theory of a cartel. A cartel grows because it hurts competitors who don't join the cartel.

I explained the game theory upthread, and I will repeat a summary again.

As the cartel gains more and more of the Bitcoin network hashrate, it can delay non-cartel transactions by an ever increasing delay, i.e. asymptotically infinite delay.

This forces non-cartel entities to join the cartel else lose their businesses.


Thanks. Fundamentals are a genre of peer review that has high utility IMO.


I am not entirely following your logic here. Are you referring to mining them on the Bitcoin chain?

I will say this which might cause you to conclude that your line-of-thinking could be irrelevant. The cartel's incentive is the value of all the business that is not already in the cartel.

Could you clarify your logic further? I think I may understand, but I don't want to try respond until I am sure I understand your point.

So, again, you have two cases:

1) Cases where the cartel cares about double spends, in which case it must get transactions into the block chain as soon as possible.

2) Cases where the cartel doesn't care about double spends, in which case, they don't need the block chain because this is the only service it offers.

Any cartel large enough to successfully make this attack work would have to handle a large enough fraction of Bitcoin transactions that it would just do them off the block chain. All the cartel would do is keep for itself transaction fees it wouldn't need to pay anyway.

But there's another reason this attack can't possibly work that's even more fundamental. The cost to the cartel of mining its own transactions would equal the benefit of not paying transaction fees on its own transactions. This attack is only sensible if zero-fee transactions rarely, if ever, make it into blocks. That means blocks will typically be full of fee-paying transactions. That means every transaction of its own that the cartel mines is one fee-paying transaction it gives up the chance to mine. So what's the point?

i belive offchain, dont know why u dont

There are (at least) two orthogonal cases of risk from double-spends.

1. Cartel is in race to protect against a rapidly issued double-spend which is trying to achieve this by propagating two spends where one ends up orphaned. Or where cartel is trusting a 0-transaction spend.

2. Cartel permanently accepts a Bitcoin as a cartel coin, without ever requiring the spend in the Bitcoin blockchain, thus the customer could at some point in the future also spend the Bitcoin and the cartel coin separately.

It doesn't seem like #2 makes much sense as a cartel strategy, so I assume we both agree it won't be employed.

So let's focus on #1.

The customer is not going to shop only one time on the cartel, because it is a cartel meaning the cartel covers a wide range of the commerce the customer encounters.

So the cartel doesn't have to worry about case #1, because they can ban the customer if the customer issues a double-spend.

The the cartel can accept 0-confirmation transactions and wait until the cartel's miners solve a block, to add the spend to the Bitcoin blockchain.

Thus my attack works perfectly well as I have explained throughout this thread.


Sorry you presented no cogent, logical argument to support that opinion.

I wrote downloadfast.com back in 2001. I did payment processing for software authors back when we had to devise our anti-fraud strategies in-house. I know these issues very well.

Joel I have had several months to think about this. I have a very high IQ. You are not going to win this. But please keep trying. I want to accept all challenges just to make sure I didn't miss something.

You can't have it both ways. If you need protection from double spends on the regular block chain, then you need to get your transactions mined as soon as possible. If you don't need protection from double spends, then you can conduct your transactions off-chain. This "attack" just doesn't make any sense.

Constant money supply is bad for crypto-currencies for more than one reason:

https://bitcointalksearch.org/topic/m.3615848

Retail cartel != MtGox

MtGox owns the Bitcoin on the Bitcoin chain

Retail cartel owns nothing on the Bitcoin chain, instead has issued the customer a Cartelcoin in exchange for the Bitcoin which was never received.

JoelKatz proposed that, not me.

Actually he may not have even proposed that. He may have implied that cartel issues Cartelcoins in exchange for Bitcoin which was received but never uses Bitcoins again after that.

Sigh.

lolz  , I am getting quite bored of this as well, we are going around in circles.

I will concede that you can't explain to me how a customer can double spend or benefit from sending coins to MtGox.

Done.

Which word of "give up" do you not understand?

You've forgotten what I already explained to you upthread. You will get no more hand-holding from me. Sorry. I like to help people, but you have to be willing to not forget what you've already been told.

Excellent, at least we agree that bitcoins cannot be double spent off-chain, unless the system has a grave error.


Which party is spending the coin again?

MtGox has a pool of coins, the coins aren't linked to any customers.  When I send those coins to my MtGox wallet, MtGox now control them.  They could spend them straight away, do whatever they want, it has no effect on the customer.

I never wrote that Bitcoins could be double-spent off-chain. Can't you read above what I wrote?

I said that the offchain coins would not be protected against a double-spend, meaning that the Bitcoin chain could still spend the coin again, which was also "spent" into the offchain.

The double-spend notion comes from the fact that the customer has gained double value from one original Bitcoin, the offchain coin and the Bitcoin coin.

If you still don't get this, please give up. It would mean you are hopelessly retarded. I tried to be nice to you for a few posts, but you just go on and on with your inability to grasp a simple concept.

Again readers, the above is JoelKatz's suggested attack, not the attack I described in my OP.

You missed my point entirely. 

My off-chain transaction debate has nothing to do with your theoretical attack.

I'm calling you out on how the hell I can double double spend bitcoins off-chain as you said here:

Exactly. That is what JoelKatz suggested. I never suggested that attack. It has nothing to do with my attack. You are conflating what JoelKatz wrote with the attack I have described. Please stop doing that.


You don't have sufficient understanding. The others here understand that I do make sense. They may disagree with whether the attack I described is likely or not, but they don't say I make no sense.

JoelKatz's attack is not likely in my opinion, so I don't know why you continue to discuss it in my thread.


Agreed in JoelKatz's attack. But that is not the attack I described in my OP. Go talk to JoelKatz about his attack in another thread. That is not the attack I described.


Trust me, there are many people here reading and they understand you don't understand. It is very obvious you don't understand. You think JoelKatz's attack is my attack.

If we aren't sending them to the blockchain ever then we are using Cartel-Coins, not bitcoins.

Look, you don't make any sense.  If I send bitcoins to my cartel wallet, I don't control those bitcoins anymore.  What I have now is a claim for those bitcoins from the cartel.

P.S I'm not cluttering this thread, your theoretical attack is baseless at best.  You proclaim to be the expert and look down upon other people, yet you can't even understand off-chain transactions.

JoelKatz implied or asked if cartels might prefer to not send the transaction to the Bitcoin blockchain ever. And keep them offchain. Did you get it now?

P.S. I don't think they would choose that strategy, so please stop cluttering this thread with this off-topic discussion on not understanding the Bitcoin technology and terminology (e.g. offchain). If you still don't understand, please send me a PM and I will explain there. I am not angry, I appreciate your posts, but please in PM so I can explain without burdening the thread okay.

Why do I still own these coins if I have spent them?

I was expecting you to say that

You are confused.

And I know exactly what your confusion is, because I used to do techsupport.

Listen up. When the customer spends on the cartel, the offchain transaction would happen at that point. So the Bitcoin blockchain still shows the customer owning the coins. Whereas for your MtGox example, the Bitcoin blockchain shows MtGox owning the coins. So you are comparing two different things, apples-to-oranges.

It has nothing to do with ineptness once the coins are inside the cartel or MtGox. Both are managed correctly and no double-spends. The double-spend is due to the Bitcoin chain showing the customer still owns the coins in the cartel case, so customer can issue a Bitcoin chain spend again even while spending the coins in the cartel chain simultaneously. Whereas for your MtGox example, the Bitcoin chain shows MtGox owns the coins, so the customer can not issue a Bitcoin chain spend again.

Let me remind readers that this offchain discussion has nothing to do with my OP and the attack I described. It a unnecessary tangent we are discussing here.

The other reason I think it would be better implemented in an altcoin, is because there are differences of opinion as to whether this attack will really occur or be successful. Because this attack involves economics on a wide-scale, not just a localized protocol game theory.

I am of course fairly worried that cartels will be the natural mode of outcome for commerce if they are not prevented from it with the protocol. Yet some of the others here in this thread think it is not likely. I disagree of course.

So I am thinking it is better to let people vote on their opinion of this issue by buying the altcoin or not.

And because I thus think you can't make this fix in Bitcoin without pissing off too many people. Which would hurt Bitcoin more in the short-term, which is what matters most to your investments.

However the argument against an altcoin would be that the cartels won't use it if Bitcoin is vulnerable to the attack they will prefer Bitcoin.

But personally I am fine with that. I just want something I can use that isn't cartelized for the non-cartel merchants. I just want freedom-of-choice when I am 70 years old.

They sure were, but now my balance is with MtGox, not the blockchain.  Your argument is that MtGox's systems are so inept that I can buy something off them and then send those bitcoins somewhere else (non-cartel).  I'm pretty sure those programmers would be fired.

You can't because #1 was recorded onchain, not offchain.