z

[Valen]

i have read that if someone has more than 50% of all the hashing power on the network they could essentially start screwing with the system and destroy it. if this is true i don't understand why smart people who know a lot about security such as steve gibson don't acknowledge or talk about this?


obviously it would take a lot of effort/money that probably only a government could pull off. but isn't it possible and if it is possible why don't people talk about it more as it seem to be the only real threat to bitcoin.

[1713876874]

1713876874

[1713876874]

1713876874

[Serge]

As far as we know there is no super-computer exists today that can play this game anymore.
I don't want to give false sense of security though. The risk exists. For any private entity who can beat network's hashing capacity it would be more profitable to mine instead of trying to corrupt the blockchain. Any pool close to or over 50% poses risk of being hacked for instance and screwing the system. Don't know what to say about authorities - would they want to screw with it in such a way instead of simply trying to outlaw it if they deem to do so.

[Valen]

you don't need a super computer

the power to do this can be purchased and set up. probably costing several million dollars but this amount is a joke to a government.

[Valen]

As far as we know there is no super-computer exists today that can play this game anymore.
I don't want to give false sense of security though. The risk exists. For any private entity who can beat network's hashing capacity it would be more profitable to mine instead of trying to corrupt the blockchain. Any pool close to or over 50% poses risk of being hacked for instance and screwing the system. Don't know what to say about authorities - would they want to screw with it in such a way instead of simply trying to outlaw it if they deem to do so.

outlawing it would have no effect. they would have to destroy it to stop it.


for an example of what i mean, look how effective outlawing drugs has been.

[andes]

Already discussed here:

Bitcoin's kryptonite: The 51% attack
http://forum.bitcoin.org/index.php?topic=12435.0

And 50% is not a magical number, hashing is a probability issue. For an effective sustained attack, you would need a high percentage of hashing power though.

[Valen]

Already discussed here:

Bitcoin's kryptonite: The 51% attack
http://forum.bitcoin.org/index.php?topic=12435.0

And 50% is not a magical number, hashing is a probability issue. For an effective sustained attack, you would need a high percentage of hashing power though.

thanks, i'll start reading it

[andes]

obviously it would take a lot of effort/money that probably only a government could pull off.

Right now you dont need a government, only a couple of tens of millions of dollars.

To put that in perspective, only in the USA right now, there are 1 million people that have a net worth of more than 10 million dollars. If a handfull of those wanted to harm bitcoin, they could.

Also the supercomputer argument is a known fallacy. Its a catchy phrase but does not make bitcoin less vulnerable to brute hashing attacks for the moment. The supercomputer argument is debunked in the thread above.

[Valen]

obviously it would take a lot of effort/money that probably only a government could pull off.

Right now you dont need a government, only a couple of tens of millions of dollars.

To put that in perspective, only in the USA right now, there are 1 million people that have a net worth of more than 10 million dollars. If a handfull of those wanted to harm bitcoin, they could.

Also the supercomputer argument is a known fallacy. Its a catchy phrase but does not make bitcoin less vulnerable to brute hashing attacks for the moment. The supercomputer argument is debunked in the thread above.

right, i should have said either a government or a person/corporation with substantial funds could do it

[peach]

I think you're confusing the Democracoin idea someone posted here last night and Bitcoin itself.

Bitcoin cannot be screwed with in such a way.

[andes]

Bitcoin cannot be screwed with in such a way.

Of course it can.

[Valen]

Bitcoin cannot be screwed with in such a way.

Of course it can.

i don't see how people don't discuss this more. it seems to be a fatal flaw in the whole system.


people talk about how the guy who wrote all this stuff solved all problems with it but he didn't.

[CurbsideProphet]

obviously it would take a lot of effort/money that probably only a government could pull off.

Right now you dont need a government, only a couple of tens of millions of dollars.

To put that in perspective, only in the USA right now, there are 1 million people that have a net worth of more than 10 million dollars. If a handfull of those wanted to harm bitcoin, they could.

Also the supercomputer argument is a known fallacy. Its a catchy phrase but does not make bitcoin less vulnerable to brute hashing attacks for the moment. The supercomputer argument is debunked in the thread above.

I'd rather see the number of Americans with LIQUIDITY in excess of $10 million.  Net worth factors in long term, illiquid assets.  I get your point though, I just think you're using the wrong metric.

[andes]

Bitcoin cannot be screwed with in such a way.

Of course it can.

i don't see how people don't discuss this more. it seems to be a fatal flaw in the whole system.

people talk about how the guy who wrote all this stuff solved all problems with it but he didn't.

It is a problem in fact. The only way bitcoin can survive in the long term, is with governments or powerful organizations protecting it. We should wake up to that reality.

This, of course is not an impossibility. In fact I see many governments allready supporting bitcoin indirectly.

[andes]

obviously it would take a lot of effort/money that probably only a government could pull off.

Right now you dont need a government, only a couple of tens of millions of dollars.

To put that in perspective, only in the USA right now, there are 1 million people that have a net worth of more than 10 million dollars. If a handfull of those wanted to harm bitcoin, they could.

Also the supercomputer argument is a known fallacy. Its a catchy phrase but does not make bitcoin less vulnerable to brute hashing attacks for the moment. The supercomputer argument is debunked in the thread above.

I'd rather see the number of Americans with LIQUIDITY in excess of $10 million.  Net worth factors in long term, illiquid assets.  I get your point though, I just think you're using the wrong metric.

I am not using the wrong metric. You can convert any asset to money given enough time. I am not saying they have to make an attack within a certain deadline. And I am being conservative, because you could even get a loan to make the attack, so even more people would qualify.

[CurbsideProphet]

I am not using the wrong metric. You can convert any asset to money given enough time. I am not saying they have to make an attack within a certain deadline. And I am being conservative, beacuse you could even get a loan to make the attack, so even more people would qualify.

It's just that net worth is a figure that's easier to fudge.  Cash is cash.  Assets can be over valued on a balance sheet or liabilities can be under valued.  I'm not really trying to argue with you, like I said I get your point, I'm just saying liquidity is probably a better measure as to someone's capacity to destabilize a market.  Good point about using leverage.

[andes]

I am not using the wrong metric. You can convert any asset to money given enough time. I am not saying they have to make an attack within a certain deadline. And I am being conservative, beacuse you could even get a loan to make the attack, so even more people would qualify.

It's just that net worth is a figure that's easier to fudge.  Cash is cash.  Assets can be over valued on a balance sheet or liabilities can be under valued.  I'm not really trying to argue with you, like I said I get your point, I'm just saying liquidity is probably a better measure as to someone's capacity to destabilize a market.  Good point about using leverage.

Yes, I get your point too, and I agree, but the problem is that liquidity is also a relative metric. Assets can be more or less liquid, but there is no precise cut line for "liquidity".

[ollybee]

The two scenarios that worry me are
1) bitcoin dosn't scale. I know i should do and I know that work is being done in this area. Ive also seen other systems that should scale fail when it came to doing it for real.

2) consolidation of hashing power. The top two mining pools combined have over 50% hashing power. this gives them too much influence. I'm not talking about straight double pending attacks but more general power and influence over the project.

[andes]

Did mods just deleted an ongoing thread called "Biggest Bitcoin threat" or something similar?

[Mod edit: It was merged into this one here: http://forum.bitcoin.org/index.php?topic=25026.0]

[andes]

Hugolp, a pm to the participants of an ongoing thread that suddenly dissapears would be polite. I lost 15 minutes and had to pm theymos to find out that you deleted an ongoing thread and merged it here.

[Alex Thornton]

Bitcoin grows too fast. 

This