Topic: If mining gets unprofitable will it expose the system to 51% attacks? (Read 2426 times)

Difficulty results in mining becoming the least profitable it could possibly be while still working.  That means that it'll only be profitable for people who are established and have built up big businesses.

Basically, it'll still be profitable but that doesn't mean it won't leave the system more vulnerable to 51% attacks.  That's why Jihan Wu controls such a large amount of the hashrate (because mining becomes less profitable -> less people mine -> system is vulnerable).

Yes it would. With no profit means less players. Less players means easier to attack.

mining will never get unprofitable,there is this thingy called difficulty
it adjusts every two weeks on average,as soon as the mining gets unprofitable or marginally profitable
the hashrate drops,blocks are being found less often and the difficulty adjusts so that the blocks finding time is 10 minutes on average
thus leading to lower difficulty and more profit for your PoW stake,hence more people will start mining and adjust the difficulty again
it is a very adaptable system and it has proven to be working
besides even after all the halvings are done and there is no substantial block reward,miners will be profiting from the transaction fees

I'll correct you in that mining will never become unprofitable for the miners with the lowest energy cost. The system doesn't have to collapse for this to happen.

It will definitely work but i think only bill gates or people listed on forbes top billionaire can do that thing, Because no ordinary people will allow to destroy a currency where they invested, It requires a billion $ funds to able to destroy bitcoin. But i guess that billionaires will not gonna risk on investing in bitcoin since it is not a very stable investment for profit.

Bitcoin will be experiencing a big, big problem once it can get controlled by only a few people. Because we are all greedy and we all want to have the maximum profits we can get, things can get so messy and Bitcoin can took a hit from manipulations and wranglings. Human nature is something that is beyond technology to cure and we are bringing it into the Bitcoin table. This is one of the many reasons that Bitcoin may not be able to be very massive as compared to fiat money...right now the volatility rate is amazing.

Yes, but not only that. What Rockie1234 said was that it makes no sense for the big whales to spend their money and energy to do something which will put their capital at big risk. Even if they can attempt the 51% attack, why would they do that?

but we never had an hard fork debate that will eventually turn real in few week, like this one, in case of an hard fork the bigger fork, have all the reason to kill the small one to destroy its competitor

if the diff go too much down, it will be even more easy to do a 51% because any entity that have a low hash could do it, do you think the random dude care about supporting the bitcoin network, the majority only want more fiat money....

let's look into the history, we had bitcoin lower than $200, but to the best of my knowledge,
relating that to the electricity costs, mining will become a loss instead of profit
but to my knowledge we didn't see the 51% attack..
i am guessing the 'difficulty' implemented by mr nakamoto is a great filter for this kind of situation,
when there are no miner, the diff will go down, much much down even your android phone can do the mining..
and when the diff go down, a miner or two will start their miner to snap the profit as much as they could, automaticaly this will give the 'decentrilized network state',
thus preventing the 51% attack

This sort of idea is already happening in the system as we know it - however not quite as you described it.

Right now, any standalone miner at home using a Laptop will find quite quickly that it is not profitable -- whatsoever -- for him to spend his resources mining. Therefore, in essence, we can imply that the majority of mining power comes from large farms who could perhaps work together in order to force a 51% majority upon the blockchain nodes which could, depending on the fork, have a major and devastating impact on the community.

This, however, is an extreme measure and is not likely to happen. Mainly because the people who wish to do harm on the community will introduce a new, unreliable fork that most pools will avoid. If larger pools were to adopt a widely disliked fork, many miners would switch and that business would no longer be profitable. Additionally, Bitcoin pool operators are in the business of making large sums of money therefore they'd want to please as many miners as possible so that they can get as much business as possible.

Finally, nodes are located all around the world. While there are many mining farms in the US (and I mean many), it doesn't even compare to the other countries such as Canada, UK, but especially China. This means that opinions are widespread and thus a dangerous fork is not likely to gain much traction because there probably won't be any collusion between different companies.

But yes, in theory this could happen. It seems as if it is already happening with the whole BU situation, however that is FUD and it is actually quite the opposite. Satoshi designed the system so that it works for the individual user and thus this theory is not a probable situation.

Well that's what we're hoping for at least: 1. Pools compete with each other enough to not have one of them take over 51% of the capacity 2. price does not fall below profitability. That's why the recent FUDs having an actual impact on prices and the bitmain complex being opened up is so worrying.

If mining gets unprofitable, than there is a risk of what you said but also there is another side. Mostly to my mind if mining gets unprofitable, than we will receive higher bitcoin price in result because of that. At the same time it's truth that bitcoin mining is now private business because it's hard to start mining with nowdays ROI and everyone who was in this game already years ago, can to continue without problems. Maybe we won't be in front of this problem.

You can also control it if you have enough capital.

so sooner or later china and bitmain will controll bitcoin

I agree with that. It costs a lot of money to build large farm.

keep in mind that the miners consumption is very low, take a antminer s9 for example, at 0.05 cent electricity and 1400 watt it only consume $50 a month in electricity

this is the money they need to cover with electricity, now just scale it and you will clealry see that they have huge margin

but since the competition is ferce i suspect that for the same earning they had before they are consuming far more than in the past

for example if an antminer earn you 0.008 currently, and consume $50 a month, right now they need at lest two of these antminer to always earn you the same amount(0.008) but consuming $100 instead of 50

this because they must stay in competition by adding miners equipment because of the diff, and this also result in incrementing their consumption without a higher return...

right now they are spending around $12M in consumtion per month to generate 1800 coins a day , which is $60M a month, ratio 5:1, this mean that bitcoin need to be 1/5 of today price to be unprofitable for them

You are right.
But everybody here trust in something different.

Does anyone expect any system with the financial impact of bitcoin to stay some little hobby thing? Its a multi billion dollar industry, of course businesses are going to crop up all around it. If companies were not investing in it do you really think the value of bitcoin would be where it is now?

Bitcoin mining is plenty profitable, just because you cant make ROI in 3 months with $0.15/kw power doesnt mean its not. Bitcoin mining is an industry now not a hobby.

As far as the 51% attack goes you also have to realize that the pools are made up of tens of thousands of miners and if any pool starts trying to attack the network people will just move their miners somewhere else. The 51% attack will never happen. It is just more FUD in an industry filled with it.

jeah that truly sucks what was once and looked like an idea of small people quickly became an issue of the corporate rich, bitcoin has been sold out and it will sooner or later face the fate of other bubbles

There are currently 5 major mining pools that are somehow miner manufacturers themselves and they thirst for each other's blood, they're constantly upgrading their hash power and will never let others to take over, even if they do it's in their best interest to stay honest and keep the wheels rolling.
And btw mining will never become unprofitable unless the whole system collapses and in an open source project essentially there are no collapses.

It's like the time line theory where the straight line goes for ever and you can't cross it or break it only you can fork and create a parallel time line in our case another version.

No, you are wrong. Blockchain can be manipulated. All we need is majority of hash power focused in the wrong hands.

If attacker controls more than 50% of the network's computing power then it is possible to modify or exclude transactions.
In that case transactions can be reversed, double spending is possible. Attacker could prevent other miners from mining blocks or gaining confirmations.

I guess it could work, but the question is why would anyone do that? If you had the power to do that, you would almost certainly own a ridiculously large amount of Bitcoin. Firstly, you would spend a lot of money, and you would essentially devalue and destroy your own currency, leading to millions of dollars lost. I can't see that ever happening.

Blockchain can't be manipulated. The spreading of the nodes around the world is securing the blockchain system. It makes there are no high trustability nodes.

It sure will and even more because a lot of home miners will lose out to the big farms and a community/country without jobs robbery prevails and the same will apply to this community if the miners lose their jobs.

Hi all

I'm new to Bitcoin and I try to find out more about how it works so please forgive me when my question is too stupid for you and try to explain me like I'm five.

As far as I understand mining is essential for the system to work, because without miners no new block can be added to the blockchain.
On the other hand mining gets more and more expensive so that only big miners with cheap electricity can afford it. That makes the bitcoin-system in my opinion extremely exposed to 51% attacks.
Since if only the big miners work on the blockchain they can manipulate the blockchain when the just big enough.

Am I right with my concern or did I made a mistake?
Please help me to understand it better, thx.