Bitcoin Forum

For those who have not read:

http://coinbrief.net/bitcoin-experts-51-attack/

Thanks for posting that. All of the fear here can get overwhelming.

So Gavin says totally not a threat, but I have some code for a hard fork laying around for when it becomes an emergency?

Well if you look at the original article the Bitcoinfoundation put out you can see that they still are concerned with it
Perhaps not afraid but concerned
https://bitcoinfoundation.org/2014/06/13/centralized-mining/

Sorry, but that post does not make my worries go away (not that i have many at the first place but sitll...).
There is nothing "definitely" in all of this explanations, nothing that can assure anyone. They are telling us that it's not probable that it would happen and that they have safety mesure but they wont use it until shit hits the fan. It's like knowing for hole in your system, but not deploying patch to fix it untill someone ectualy exploits it. I'm not software expert, but this really sounds so....not samrt (wont use that other much stronger word).

According to the article, they aren't afraid of a 51% attack because it'd be easy to address after the fact. It wouldn't undo the damage, it would just prevent it from happening again. So it's rational to not be afraid of that happening, because it will only happen to one/a few extremely unlucky merchants or services. I would worry if I owned a large-enough target though. Like SatoshiBet.

why let it happen and mar the reputation.. I guess in the future its a move for the devs to get some cheaper coins while the system is in a mess and the markets in panic.... I think its selfish and above all foolish..

Doug
d57heinz
In Bitcoin We Trust!

That article uses quotes from 2009. Recently, my brother reminded me that I claimed a 51% attack could not happen because people would desperately add hash-power to the network (even at a loss) to stop it.

With large miners claiming to be on Ghash.io for reduced variance, this is clearly not happening. Though I just checked: Antminer S1s (https://www.bitmaintech.com/productDetail.htm?pid=00020140107162747992Ce5uBuxW06D6) are currently out of stock.

Philip

I have seen recent news where petamine is pulling off ghash and multipool.us had it in there news recently that they were pulling off ..  That is some bs that those larger pools are hopping onto ghash..  ive moved to guild and im happy with the payouts.. although they aren't as lucky as ghash Id rather be getting something rather than support the demise of the entire network.  even if they don't have malicious intent its the fear of the "possibility" that causes market to crash.. 

Edit: Ohh and I also have read that the s1 is no longer going to be produced... so that should slow things down for the little guys but the big miners.. moving onto s2 for sure or dragons..

Doug
d57heinz
In Bitcoin We Trust!

Why Bitcoin Experts Aren’t Afraid of a 51% Attack
Anyone not concerned about, or afraid of a 51% attack shouldn't be in control of the code base or have major influence, imo.
We cannot have BTC ready to go mainstream with huge security risks.

How much hardware does GHash have, versus the hardware contributed by its users? Given that GHash's hash rate varies so much, I'd guess a significant fraction of its hashing power is decentralized. Thus, if GHash ever started to execute an attack, its users would immediately leave the pool, rendering it impotent. There is no problem.

I wouldn't bet all my money on that.
Users did not leave GHash as it was approaching 51% and not even when it got there.

That being said I will repeat myself.
The 51% we witnessed the other day was a demonstration of power.
For what reason I don't know, maybe it was a response to the 30% network rate of the Chinese and their meeting.

I remember a while back (around February I think) GHash closed registrations to new members and blocked miners as to not accumulate 51% of the network hashrate.

Why didn't they do it again?

My guess is that GHash has a lot more than 51% and they are just hiding it.

Then again I could be wrong.

So if the 51% is no big deal, why did the price go down nearly $100 and why is it going back up again now that the threat has passed?

I think it is a threat simply because people new to bitcoin react to it. I honestly don't think that Ghash would be stupid enough or corrupt enough to do an attack. I never said that - my line of thought is that nobody would join bitcoin if the risk is clearly possible, and those who do not completely trust the system (let's face it, these are many) would pull out as soon as the risk appeared. That, in my opinion, is the real question at stake.

The price of bitcoin was definitely on it's way to $700 US before this Ghash fiasco. Then it went down to the mid $500s. The fact that it's going up again now shows that this has nothing to do with the FBI coins.

On another note any flaw in the system detracts from the value of bitcoin. As we know, bitcoin has intrinsic value because of its qualities as a payment system. Flaws in the system lessen that value. These should really be addressed to improve that value.

+1

Clearly no pool has any incentive to mount a 51% attack so please can we forget about that?

The more significant threat posed by centralisation of mining is that it creates a small number of chokepoints . It thereby exposes the block chain to the risk of Court-mandated mining policies. If for example a US Court were to issue an injunction requiring the major pools not to mine any chain that includes transaction X, life could get very messy. In effect the result would be Court-enforced hard forks.  It is probably a very low order risk, but certainly more plausible than a 51% attack.

Fortunately pools do not as a rule own or control their own hardware. Thus it would be trivial for pool members to redirect their hashing power to another pool that lies beyond the jurisdiction of the relevant Court.

So, what *is* the incentive of ghash.io? They aren't charging any fees. Why are they paying for setting up a mining network that controls so much of the mining power out their own pocket and then just give it away for free? If anyone wants to do a 51% attack this would be the cheapest way to do it.

You need to go to their site and youll see that they are earning ton of money. But stilleven with that, we "have to trust em" and that's exactly opposite of what btc was made for.

Read their last announcement on that matter and you'll find out they're planning to launch a instant payment processor leveraging their massive hasing power.

Plus they are selling ghs for a very long time, and I can assure you that their prices aren't cheap.

45% bitfury hw owned by ghash.  55% customer hw that use ghash pool.

they've said a new feature will be released: people who buy hashing power from ghash.io could decide to point such power to whatever pool they want.

thats the question.

Al this fanboys post  says "don't worry,they are good guys and wil no do it"
wtf?? Thats's shit.