Bitcoin Forum

This is serious shit going down.
http://newsbtc.com/2014/06/08/bitcoin-community-abuzz-ghash-ios-uncomfortably-high-hashrate/

Ghash.io at 47% hashrate for the last 24 hours.
Currently between 39-42%.

Just knock off one of the other big pools and its FORKING TIME.

*holy shit*

http://i57.tinypic.com/23mvpe8.jpg

Um, it's currently between 39-42% on ghash...you may want to update your post.

Is it better now?

http://www.reddit.com/r/Bitcoin/comments/279sex/ghashio_double_spending/

here is the suggestion that it has been multiple times -

by colluding with other players , this makes perfect "Nash" sense.

Very likely and its time to invest in some altcoin :)

Ghash.io did turn off 'some' hashes to lower their network %.

there are others attack that don't require 51%, but they are not 100% guaranteed to work, less strong than 51% of course

Did I hear anything about decentralized mining?

Myriadcoin is here to fix that

https://bitcointalk.org/index.php?topic=483515.0

Thats a very nice facetted discussion on reddit.
I personally believe they already control more than 51%.
The implications of a double spend are minor, just to distract.

Such a stunt, such a FUD situation would create a win win short selling opportunity for which big player?
The leverage would be stellar, they could multiply their holdings in a couple of hours.

Not over. At 43% now again!
https://blockchain.info/pools?timespan=24hrs

Think twice. It not in their interest to attack bitcoin. Millions worth of hashpower they own, they will do everything to protect against 51% attack. Why are you affraid?

45% and rising. If it forks, price will drop like a turd, no doubt about that.
It would be in anybodies interest who is short the market.
And I'm not afraid, I'm actually looking forward to it.

bitcoin will be 69'd before its 51'd   :-*

I think you wait for something that will not happen. They had close to 51% multiple times before...

hahah that picture allways makes me laugh, alot of truth in there
but srsly, ghash.io has an awesome pool, but due to their insane growth, they should really make more servers, so that , even tho hash is with them, stays diversified, and prevents forking.
after all the bad news this year, we realy dont need a fork

Maybe not, but maybe yes. Murphy is watching you.
Anyway, it doesn't really fit my understanding of a secure blockchain any longer.
BTC's decentralized system is broken for a long time.
If it happens BTC will loose a leg of it's throne. An avalanche will be triggered.

http://www.saturdayeveningpost.com/wp-content/uploads/satevepost/Trapeze-Summer-1971_rd.jpg

These scare threads are stupid. "HURR DURR POOL HAS 51% OF MINING POWR" What are they going to do? It's not like miners will continue to support that 51% after an attack. The pool would be finished. There is no incentive whatsoever for a pool such as GHash.io to attack the Bitcoin network.

Dude, do you know who runs ghash.io and who owns it?
Check that out and come back later.

Hardware mining is fail. Use NXT.

You mean cex.io? Yes, I happen to have an account there. There is STILL no incentive for Ghash to attack the Bitcoin network because it would mean a serious loss of customers for CEX.

You guys are so cool.But the risk is there.
We have to "belive" in good on gihash?

I have to trust all my money in "they will never do that"?

doent'l like.

uh...no.

51% attack isn't a fork.

Does anyone KNOW what actual % Ghash owns? Anyone with half a brain knows that if miners see to much % at Ghash, they just point their miners at another pool. I just wish more miners would realize that bigger pools don't mean bigger payouts. MAYBE if you pool hop just right, but in the long run it all averages out.

Do you really think so? Join the party:

https://www.betmoose.com/img/57.png (https://www.betmoose.com/bet/ghashio-will-reach-51-or-more-in-the-next-month)___________

Ghash.io will reach 51% (or more) in the next month (https://www.betmoose.com/bet/ghashio-will-reach-51-or-more-in-the-next-month) Options: Yes (https://www.betmoose.com/bet/ghashio-will-reach-51-or-more-in-the-next-month#1) | No (https://www.betmoose.com/bet/ghashio-will-reach-51-or-more-in-the-next-month#2)

Someone else like Cloudhashing or another large-scale hosted setup would start getting close enough to ensure that 51% becomes impossible for GHash.io to pull off, in conjunction with, say, some of the smaller mining pools merging to better increase the chances of them getting shares. Things will gradually move towards share or contract-style setups due to economies of scale. A third or fourth pool of a similar size to both would in effect be increased insurance of the chance of 51% ever occurring.

TL;DR, the odds will shrink in the future of a 51% attack occurring through consolidation and competing services.

47%  :o

How would you verify that? an attacker keeps their hashing secret until they release their private copy of the chain.

people should leave Gash... its too big.

Slushies miner here.. but I only have 720 G/hs..

I think it should be common pratice to leave any pool at 35%.

+1.

or even 33 or 30%.

...

Non-expert OROBTC would like to see a Discus Fish, a Slush, a BTC Guild, an Eligius, or others make it easy and profitable to cloudmine for those of us not ready for primetime, but who want in.

Then droves of people like me would sign up! 

"AMF" to GHash.IO worries!

What´s say other mining pools? 

Make it worth our while, maybe you will get rich(er?)!!!

Even if gigahash was at 75% it doesn't mean Bitcoin has been forked or 51%ed. It just means that they would have that option. I'm certainly not saying this is ideal or good and I personally believe in p2p pools, but there would be no legitimate reason for any pool to 51% Bitcoin unless their goal from day 1 was nefarious.  

All that being said, there are some other really nice pools (slush being my recommendation) out there besides gigahash.io, that might be worth a try for some of you to help even things out a bit ;)

It'll be interesting to watch the price of bitcoins if Gigahash goes over 51%.  My guess: it won't change much.  I suspect that the typical bitcoin user doesn't worry about a 51% attack all that much.  In any case, even if Gigahash gets 51%, unless they aren't legitimate miners and are someone with a vested interest in taking down Bitcoin, which I suspect isn't the case, it's in their own interest to not execute a double spend attack.  They have the most mining power and the coins that they're generating will be devalued if they do, because them hitting 51% might not affect the price of bitcoins much.  But you can bet them executing a 51% attack would definitely negatively impact the price of bitcoins.

Ultimately, I do agree with others who say that miners in Gigahash would be wise to switch to another pool until they get down to the 30% range.  Even if they have no intentions to do a double spend attack on the network, the mere possibility of them doing so might cause a bit of a panic if I'm mistaken and this is something that typical bitcoin users worry about.

Another thought. A real nice TODO for the next version of cgminer would be a pool hop function based of pool hash %.

So if pool A >= 30% move to pool B, etc...

It is not a good idea to let them have 51%.   They could decide at any time to engage in selfish mining and institute a monopoly.
51% power means they could solve 100% of the blocks by producing the longest chains and shut everyone else out...
IF they chose to do that.

I'll CONSIDER investigating NXT when the first google result isn't this: http://www.wwe.com/shows/wwenxt

Until then, YOU are the fail, and nobody cares.

Ah another fear mongering thread. All of the screeching does more damage than the infinitesimally remote chance that someone might destroy their own profitable business in order to hurt bit coin.

1) 51% by itself is not a problem. It becomes problem if person who is in control of those 51% does something silly which is highly not in their intrest

2) Fear of 51% attach should not be in "someone massing large amounts of ASIC hardware" or "someone attracting more than 51% of mining power". It's much easier to destroy bitcoin network. All NSA (for example) needs to do is to get to leaders of top 3-4 mining pools (somehow...some dark secrets etc.), and it's game over. As users switch from largest one to smaller pool, nothing change. They are still getting into controlled one. Person / system who would control those 3-4 people (and we all agree it's not hard to control 3-4 individuals) would be running bitcoin network as he wants and would have ability to undermine it so hard that it wouldnt come back up

3) Hardware is not protection of the network. Bitcoin is not strong because of ASIC's, it's strong because of it's protocol. So, if you need to protect software, you dont protect it with hardware, you protect it on software side. Soltions to "pool mining", "51% attack" etc. are out there. Devs just need to implement them inside code.

51% is totally a problem.
if someone has 51% of hashing power then we have to trust they aren't going to shut bitcoin down one day.
if you want a system where you need to trust someone then it already exists, its called a bank.

Right now it is 48%. Soon Ghash.io will remove more of their own hash power and it will come down to 40%. But when they'll provide all power to deliberately reverse a certain Tx, it'll be almost 70%+. It is now indeed required to find out the real owners of Ghash.io or CEX.io (https://bitcointalk.org/index.php?topic=647561.0).

I feel uneasy about this.  All it takes is GHash.IO pool operators to turn "rogue" and double spending coins like crazy.  In theory, it'll hurt their Cex.io cloud business and yada yada but do we really know their true intentions?

Not panicking, but uneasy for sure.

I don't think they will undermine their own business model. How much can they make out of double spending before somebody detects it and bitcoin looses all its value due to the loose of trust?

They are not idiot. So they wont do double spending except for certain very specific transactions. That is not a big threat here. The threat is they are hiding their real power. By showing real power, they can force price drop at any point of time and again hiding it they can take the price up.

I doubt they would ruin the Bitcoin network with a 51% attack. CEX.io, who owns GHash would rather keep CEX.io open for an extra 10 years, etc... Since it would be more profitable than to suddenly run away with BTC gained from double spending.
That would be my opinion but cannot be guaranteed.

Mining monopoly (mining 100% of blocks) is bigger threat than double spend if entity gains 51%.  More damage .. more profits ...and arguably not even fraudulent or dishonest.

Make no mistake.   No pool should be allowed anywhere near 50%.

in the end greed always wins  :-\
trusting a company with your interests is not a decentralized system

Ehhh nothing bad happened yet. Although I don't like to 'trust them' to take care of the network - I am more concerned with the fact they're not slowing down and that they're still the best option for mining, thus, the problem is with the miners and their incentive structure.

Even if ghash gets over 51% of the network doesn't mean they would attack it via a 51% attack. They have an enormous amount invested in the BTC economy and if they were to successfully launch a 51% attack the confidence and price of bitcoin would be greatly reduced.

+1

Bitcoin is based on greed!

Greed winning means they don't do anything malicious with their hashing power because it is counter to their financial interest to do it. Yay for greed.

I strongly disagree that Bitcoin is based on greed.

Bitcoin is suppose to be a way to stop greed by decentralizing money. When you have central payment processors the payment processors will have an outsized level of profits.

Greed implies a vice of over selfishness.  You could say that miners have a rational self interest to earn block rewards, which is also in the best interest of the community because it provides network security.

*AWOOOOOGA AWOOOOOGA*

Deploying my 45GHs Jally & R-box to fight of the 51% horde...

*AWOOOOOGA AWOOOOOGA*

Exactly. It would be more accurate to say it is based on rational self interest.   

The dollar and other fiat are already 1%ed, nothing that bad can or will ever happen to Bitcoin.

Still at 48%. Again, I don't see double spending as a serious threat.
But a big dead certain bet on derivatives, followed by a fork panic selloff could have devastating effects.
And the most uncomfortable fact is, that there is no quick fix for it. They have you completely by the balls.

I think this is pretty serious.

I remember in October we had over 1k nodes, now we have 200.

GHash has mined 5 blocks in a row today.

Bitcoin is totally centrallized. Even if GHash is trustworthy it would be a walk in the park for the US or a US bank to take over GHash now and just destroy BTC.


If we don't fix this i don't think btc has a realistic chance.

Please educate yourself on this. Spreading overblown fear is worse for bit coin than Ghash.io

BTC combines the good features of capitalism and communism.

People work for the greater good by protecting the network (and thus their investment in mining hardware and bitcoins themselves) while still allowing a free market economy to flourish with near instant, secure, trust-less payments.

Disclaimer:

I shamelessly stole this from another thread in this forum.


Andreas Antonopoulis addressed this at 49:13 in this video:

http://www.youtube.com/watch?v=bTPQKyAq-DM#t=2942

That applies to Bitcoin, but not to it's new financial markets.
The more I think about it, the more similarities I find with cases where whole fiat systems were destroyed, or at least damaged to a degree,  with methods alike.
The perpetrator of those practices, whose name I don't want to drop here, took out billions with each of his coups.
Please stop denying the possibility, its there.

Cant resist the opportunity to post this:

https://i.imgur.com/09SeYBA.png

Here's a proper perspective on 51% attacks.

http://www.youtube.com/watch?v=bTPQKyAq-DM#t=2942

Well, basicly, you have to trust few individuals now too. Few owners of pools, or few individuals that pull code requests for BTC core etc. It's not as "no trust needed" as most think it is.

I suppose the developers could technically fix this with a software upgrade to the way mining is done, but it'd require a hard fork, which would be kind of a nightmare.  That's definitely one big advantage of Peercoin over Bitcoin though.  That and the power thing, the amount of power used to mine bitcoins is kind of insane.

Suppose, but it's failing partiali. ASIC's made it much more centralized than uncentralized. Not fighting mass pooling is making it even more centralized. Devs under paws of largest mining hardware companys, again not so uncentralized....
I love BTC, i hold BTC and i buy BTC and i use BTC, but let's not kid ourselves. We all should know how things really are. BTC is far from it's initial idea.

They could fool the network for a whole 10 minutes before being kicked out. The protocol would then be changed so that they cannot do it again. This is pointless fear mongering. Do we really want those same potential investors reading the constant panicked screeching on here about something that is just not at all likely to occur?

Not only that it CAN be done this way, but it SHOULD be done this way.
"Hm i have software problem...should i fix it by fixing software, or should i fix it by using hardware". Cmon now...we all know answer to that question.

First of all, it would take more than 10 min.
Second, something like that would ireversably criple, if not instakilled trust in BTC and it would never recover from that.
Furthermore, if you know you have possible point of attack, and if you wait for attack to happen to fix that hole you arnt that smart really. If you are aware of hole, you fucking fix it NOW when it's safe. You sit down, you plan, you test and deploy fix. You do not do it under pressure and in haste.

Or am i wrong?

All Andreas did was mention in this video the possibility of someone pulling off this attack for profit and why this is not feasible. That aspect is obvious and needs no clarification.

He didn't say anything of the possibility if a bad actor's intention was to destroy Bitcoin, but exactly that would be the real reason for a 51%-attack and it costs only a small fraction of money world banks have. Nipping the competitor in the bud and laughing how cheap and easy it is - that's where the real danger lies.

Not profitable, not feasible?

The max leverage for CFDs on Bitcoin is at 1:20.

- Create a nice little bull run, or wait for a bullish sentiment (just happened)
- Buy another coin for your BTC, so it won't hurt the exchange rate (just happened)
- Short as many as any broker lets you, or issue some paper yourself
- Pull your stunt
- Cash out and walk away

what does that have to do with 51% attack?

anyway, yes it possible but you need lots
of money and it could fail as your attempt
to create false positive sentiment can
turn into (or meet) real positive sentiment...
plus the fact that there's not much liquidity
for shorting Bitcoin right now.

What does this mean again?  Picture makes no sense.

$88mill @ $2/GH = 44 PH which is < 88.19303 PH network hashrate or roughly 49% not 51%

Close but no cigar.

Hello Neo, my name is Morpheus.

You have come far and have accomplished to be the major player in the GHash power.

I am letting you choose from 3 options:

Take the red pill, and crash Bitcoin together with all your fortune and investment you have made.

Take the blue pill, and pull a double spend here and there and hope nobody notices.

Take the yellow pill, Take NO PILL and KEEP FINDING BLOCKS ONE AFTER THE OTHER!!!!!


Make your choice but do it wisely......

What I don't understand about this is why miners wouldn't join another pool if they see their current pool is in such a large majority.  Who wants to be part of the downfall of the currency they are actively trying to mine?

They should be.  Like someone said, there should be a guideline to unjoin or not join any pool above 35%.

The danger is that if a pool got to be 51%, they could choose to shut everyone else out,
gain 100% of blocks, and then they would be the ONLY pool anyone could make money from.

If we're all 69'd before, during and after it's 51'd, not many may consider 86'ing is my 57'd (think Kerry) thought of the day.

Before I penned the above, I asked my 7-sided dice if I should do such, whereupon the single rolled answer was 42, hence you're ability to now appreciate my 21,193rd post.

Is it sad that made perfect sense to me?

Oh hi.
I had enough of those pills actually and decided to stay cool and keep mining.

Damn, it's 44% in the last 24 hours.

https://blockchain.info/pools?timespan=24hrs

This is really dangerous, boycott GHASH.IO!

No, there are too much interest to make an attack to the bitcoin block chain.

I don't think you got the last part of that right.  However, I guess it's a matter of balancing overall best-interest of your community versus personal best intrerest.  I'm not a miner but I guess as individuals everyone has incentive to join the pool with the best deal/offer.

Even if Ghash.io has the best intentions in the world, the potential for a hacker or rogue employee to gain control of the mining pool and conduct an attack is significant.  The whole premise of Bitcoin is not to TRUST a single entity anyway ..

Why isn't it right?

I suppose that as soon as that happened, miners would leave...but they could certainly take full control for as long as they had the majority.

So true. So what are possible solutions?

People must leave gash. Already happening .bitfury pulling out. Hopefully others to follow.
More 0% pools should start too.

I am worried along with Peter Todd, Mike Hearn, etc.
There is scenarios were it wouldn't matter what the miners, Ghash, etc do.
It is 100% possible...and if you don't believe it then you should consult for btc core developers.
The problem isn't the double spend...you get 51%, hard fork, and an entity could change the rules for miners and how they are confirming transactions. Please see below.

Check out this great interview with Peter Todd who goes through the process of a hard farking.
https://www.youtube.com/watch?v=lX0imwGHK0A

I don't think it would be any 1 pool that would do this for other than monetary purposes...but just that it is possible is concerning and a weakness in the scalability of btc.

I still love you bitcoin :-)

Any update on this scenario?  There was a lot of talk about this two weeks ago.  Did anyone pull out of ghash?  Can no one compete with them?  What's the current situation looking like?

Even if ghash were to get hacked there would be nothing to stop the miners from simply leaving the pool in mass in the event ghash/a hacker were to use ghash's hashpower to launch an attack

Is there a .info site I can look at to see the current distribution?  I'm trying to find out an update to this topic but I don't know where to look for the latest mining pool stats.  Any suggestions?

*blub*

I like Bitcoincharts.com (https://bitcoincharts.com/bitcoin/), but they appear to just use the Blockchain.info (https://blockchain.info/pools) data.

NXT is proof that no one really buys anything with Bitcoin. It's mainly for speculation.

Well done - down to 38% so far
Where's that dude that was supposed to be starting P2Pool?

that made no sense.

and NXT is irrelevant.  right now it doesn't even have a Wikipedia page.

The 51% stuff is overrated. No one would kill what they have control, and what can give them billions of $. A 51% atack in the bitcoin network would be the equivalent to an action movie like Olympus Has Fallen happening in real life.


Even the effects of the 51% attacks are overrated. It would be the biggest trollage made, but with few real effects.

Don't you judge me because I drink and post! I was so wasted that night that I don't even remember what I was thinking when I wrote that. lol

While there are many other threads on this, the key thing is that if Ghash hits 51% then bitcoin ceases to be decentralized.  There are lots of things they can do that don't destroy bitcoin but make it much less pleasant for other miners.  While they can't take our coins, they can act in a very opportunistic manner towards other pools.  The people over at Hacking Distributed have written on this quite a bit and proposed a solution they seem to think will work but it would require a hard fork.

I am concerned by this, though not in a panic.  I hope someone else, maybe the bitcoin foundation, will start a no fee pool until someone comes up with a business model that can match Ghash.io.

I was surprised to learn that the original white-paper (https://bitcoin.org/bitcoin.pdf) addresses this to a certain extent:

That implies that Satoshi expected this to happen on occasion (and it has in the past, some other old-timer mentioned Slush, Deepbit and BTC-guild). It also implies that he expected the mining industry to be very competitive by the time the mining reward drops to 0.

What is different this time is that most of the hashers pointed at Ghash.io don't seem to understand why it is a problem. While it it true that incentives mean this is not an emergency, it is still not a good long-term situation.

What is supposed to happen now is that people seeing the risk of centralization add more hash-power, and hashers (which I think Satoshi did not anticipate) point their hardware elsewhere.

I'm more worried about some idiot starting a nuclear war than a 51% attack.