Bitcoin Forum

I want to know is there any other service to check the claim by BlockChain.info ?

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

Following addresses are marked for Double Spending :-

1. https://blockchain.info/address/1AF4og9Epgw7Q7hVzNeDf8ZAvzRhJ8pQG

2. https://blockchain.info/address/1H5NvB7W5hGhf3aPACDZPam7vmy3bYuTDa

3. https://blockchain.info/address/1BX5YoLwvqzvVwSrdD4dC32vbouHQn2tuF

4. https://blockchain.info/address/1BwZeHJo7b7M2op7VDfYnsmcpXsUYEcVHm

5. https://blockchain.info/address/1A73ExsM2doRwTLp82rv5U36QHbBFmHD1X


Can it happen that GHash.IO is now actually 50%+, but they are not using all of their mining power ?

Why other pools are unable to compete with GHash.IO ? What is their X-factor ?

I used to know Bitcoin is trustless. Why should I trust GHash.IO more than Reserve Bank of India, my country's central bank ?

Update: I have changed the initial title from 49% to 51% as I can see it has now reached 51% !!!

Request to Mods: Please dont move it outside Bitcoin Discussion. I can see other GHash.IO threads are here too. Moreover, its not about GHash.IO, its about 51%, its about Bitcoin remains TrustLess.

You are looking at the 24h stats.

I think they took measures to lower their has rate down: https://blockchain.info/pools

Still, I think they are just hiding hash rate.

None the less I couldn't care less.
It would be stupid of them to attempt a 51% attack.

Double spends occur with all miners that have large hashing power.
Nothing new there.

It's a fuk;['ng problem, and everyone one here is closing their eyes and say "dont worry about your money ,they are good guys".
Wonderful.

1. They have little or no fees (0% last time I checked).

2. The cloud mining website CEX.IO uses (owns?) GHash.IO. When someone buys a cloud mining contract there, the bitcoins are mined using the GHash.IO pool.

I'm not an expert so I could be wrong but I think this is why it's so popular.

Hi,


this is possible. Here an exemple:

I have 10 GH/s Hardware power (connected to GHash.IO), and I have also 20 GH/s mining contract on CEX.IO (also connected to GHash.IO).

Since 20 minutes:
-> impossible hardware connect to GHash.IO  (so I changed now to BTC Guilde, works fine)
-> my 20 GH/s on CEX are turning only about ~ 15 GH/s since 15 minutes @ GHash.IO

... just some impressions of the moment from a little miner.

Best regards.

They're switching with 50% and 49%. It's dynamic.
But I believe it's gonna be okay for now. They should take care of it in some way though.

It's so popular just because of this reason. It's the biggest pool and everyone goes there. They find the most blocks.

Bro, Ghash is not for little mining system ... look at your DOA, it will be high with a "minimal difficulty to 8".
move to an other pool with variable difficulty (like slush's).

you win the same amount of money.

Ghash need to put in some fees and that would solve the problem..

Thank you Sir, I will look closely at

This is very bad imo. I don't think people realize what a 51% would do to Bitcoin.

and it's a useless way of mining ... a pool that win more block don't pay more !
you win BTC with a constant GH/s speed.

even in a little pool ... you win the same amount even if it don't find more than 5 block per day.

I know, I just wanted to say that people find that attractive and have the wrong opinions. That's what lead to these 50%.

They are working on option that will enable you to redirect their hardware out of their pool. So basicly you rent their hardware but you mine at pool of your choice.

So, CEX.IO is putting up tweets instead of actually doing something.

https://twitter.com/cex_io/status/477377921234264064

In a free market economy, u cant expect the leader to step down. The competitors should step up.

Or it should be regulated by authority (in this case bitcoin protocol itself). It should be possible to force anyone from amasing hash power like that on protocol side. It's not Ghas that should fix this, devs are ones that need to secure network on protocol level.

You can't just blacklist an entire pool.

You cant blacklist, but u can cease its mining power programmatically with protocol level modification. Please read the proposition => https://bitcointalk.org/index.php?topic=650778.0

But you talk about leaving it at 49%. That's still way too dangerous.

It can be set to any "max" level...even "only p2p" can be forced on protocol level.
Best and only way to protect network is portocol, not hardware.

Exactly and I dont understand why 49% is at risk, though its just a max variable that the community can decide upon. But whether a protocol level modification is possible and be accepted is a bigger question. I believe except for GHash.IO all other miners will accept it. Probably the independent participants at Ghash.IO too.

People keep calling it 51% attack which makes the impression that only 51% or more would allow the assciated attacks on the network.
However, it actually is a "more than 50%" attack, which can be done with as little as a consistent 50.00001% of total has power.

GHash.IO actually crossed 50% today. I saw it in the blockchain.info graph. But, it was below 51%. So it was not shown in digit. Would be interested to know whether any other portal is providing this graph of hash rate distribution ?

51% means that double spending would be at a 100% success rate. You could still endanger Bitcoin in such a way with 49% as well.

I'll again repeat myself and say that Ghash could keep all the hashing power if they were to split to independent pools.

Oops !!! Thats a problem I did not consider. Even a protocol level change cant stop it then. Only market competition can counter them.

It can further be used to lock down addresses by not processing transactions that are made from that address and by refusing all block that include transactions from that address.
Other miners would then be faced with either having to lose their mining reward (because GHash.io ignores their block and just builds a longer chain which will overrule the block with the transaction in question, or having to not include any transactions of addresses GHash.io says they won't build blocks on.
Ofc, with miners often being heavily invested in mining hardware, they would always want their reward and therefore obey GHash.io's rules (in order to at least get something out of their mining investment).
That would lead to the network adapting to rules set by GHash.io rather quickly and therefore making it impossible to switch back even after they lose their has dominance (because who wants to step out and have his blocks refused by the network first?)
It's a dangerous situation and I do not like it =/

Or just change diff for any entity that has hash rate above certain percentage of whole network hash rate. Than pools and miners would be forced to split to smaller groups and pools.

They can still lock down addresses by not processing the Transactions and not building on top of blocks including said Txs. It they have the same rules it does not matter if they appear to be any amount of pools, their efforts are going to be pooled

Have they started double spending yet?

you cannot automatically double spend just by holding 51%. you have to have code that allows it, meaning that they have to intentionally change the rules to allow it.

a 51% attack = 51% dominance + intent to attack.

many believe GHASH has no intent to shoot themselves in the foot by doing anything nasty

so now the future of everyone holding bitcoin depends on some anonymous guy not doing anything nasty?
if they continue holding more than 50% of hashing power for a few more months im personally converting all my btc to gold.

I believe, they actually hold more than 50%, but is not using a % of their capacity. But I disagree that the future of Bitcoin holding is in their hand. Even if they hold 100%, the cant sign a transaction. So they cant ever move Satoshi's stash or yours. They merely have the choice to chose Tx to be included in their mined blocks. So, if they include a double spend and can mine 6 blocks consecutively, u may assume that would be permanent in the n/w. But, as soon as they come down below 50%, u can again use coins w/o risk.

Moreover, they are not fully anonymous. Jeffrey Smith is Cex.io’s Chief Information Officer as per http://www.cryptocoinsnews.com/news/bitcoin-mining-pool-ghash-io-is-unapologetic-risk-theoretical-51-attack/2014/06/12

It's too bad that other pools can't compete with Ghash.io

I don't think that it's the people's fault. It's an open market and they're providing a better service. No matter if you like it or not, that's the way it is. Because besides all the bad things being heard about them. It's obvius that there has been much work put into their service.

they almost had 6 blocks in a row, lucky discuss fish slipped one in there

Run to the fucking hills! SELL!!! RUN!!! FIRE!!! SEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEL!

So Ghash are just securing/gaurding the network against other malicious attackers

It sure looks like that  ;D
If bitcoin was about finding central power that secures whole network, ghas would be it.

Some suspicious double spend attacks were recorded lately but we can't tell if it was them for sure. But it doesn't really seem like this is causing large scale problems so far.

as long as they control a majority of hashing power they can rob exchanges by sending bitcoins to an exchange, converting them to litecoin/fiat and then canceling the bitcoin transaction.
bitcoin is going nowhere if we have to trust someone else not to erase transactions.

Yes because those are every day happenings. It happened before it will happen again...even if no pool has more than 10% hash power.

I'm not sure about other harms the miner may cause with 51%, but the one u r suggesting is not possible. Remember, exchange is big player, just like a miner. They wont allow a miner to play in their ground w/o 6 block confirmation and once u get 6 block confirmation, its almost impossible to reverse even with 51%. So, robbing exchanges with 51% is not possible.

It's not, it would take 301 Blocks or a bit more than 2 days of mining on top of ones own chain instead of the currently highest one in order to reverse a a 6 conf. Tx.

The result would be that at a consistent 51% you would get 154 blocks of 301 blocks with the rest of the network getting 147 blocks, which is a difference of exactly 7 blocks. Since the rest of the network had a 6 blocks headstart (remember you waited for 6 confirmations), you are now 1 block ahead. Release the chain (which is the currently longest) and the 147 plus the 6 blocks headstart including all their transactions are now void including your transaction with 6 confirmations (which actually had 153 confirmations by the time you released your chain).

And that is only if you start your attack after 6 confirmations had already taken place.
If you start accumulating blocks and withhold them, you will always have the longest chain because you have more hashpower. Now you wait for the Tx to get 6 confirmations (avg. of 1 hour), trade your coins at the exchange, get a payout, and release your chain, which is longer than the 6 conf chain on average (on average you won't have 7 blocks yet, but you are going to find your 7th block before the rest of the network and overrule the 6 conf Tx.

Note that this is all based on averages. It might take longer or shorter, but on an average, this is how long it will take.

you are wrong, with 51% you can reverse any amount of confirmations.

When you have Bitcoin dev Peter Todd dropping half his coins because he thinks this is a real problem, I am minded to think this is a real problem. :-\

http://www.reddit.com/r/Bitcoin/comments/281ftd/why_i_just_sold_50_of_my_bitcoins_ghashio/

"'If you can keep your head when all around you have lost theirs, then you probably haven't understood the seriousness of the situation" - David Brent (fictional character, The Office)

Exactly. The rule of thumb is to take the amount of confirmations you want to reserve times 500 plus 1 will be the amount of minutes it takes to reverse the transaction if the attacker has a consistent amount of exactly 51% of the hashpower.
That translates to around 20 blocks eradicated per week (if they are in the past). For future blocks the attack can be instant after a amount of X confirmations is reached (like 6 conf. deposit requirement on an exchange. After its reached it can be reversed right away if the attacker planned the attack before the first confirmation happened).

You are considering it only from technical angle. From that angle, by an intermittent 51% attack, the whole blockchain can be re-written. But bitcoin is not only a tech product, but also a financial one.

Lets say, if their holding GHash.IO can buy an island now. But, the moment they try to rewrite 6 blocks for 2 days, the purchasability of their holding will come down to a cup of tea on that island.

That is why 6 blocks will never be re-written.

the amount of damage a single 6 block rewrite can do is massive, they could steal tens of millions from an exchange in a single week as a last bonus before they disappear into early retirement.

Just because you can rewrite the blockchain does not mean you have access to the private keys. So you cant actually steal coins. You can however spend coins more than once, but you must own them in the first place.

1. send bitcoins to exchange
2. convert bitcoins to litecoin/fiat
3. pull litecoins/fiat from exchange
4. double spend the bitcoins back to yourself,
5. you now have your original bitcoins plus litecoin/fiat, your money has doubled.
6. go back to 1.

i call this stealing coins.

Your coins have doubled just in number, not in its purchasability. Before the double spend, if u could buy a harley-davidson with your coin's FIAT value, after the double spend u'll be able to buy a plastic motorbike at a countryside fair with your coin's FIAT value.

Value comes from acceptance. The moment one starts mass double spending with 51% power, the moment they lose their coin's value. This is the same reason a government does not print FIAT as much as they wish.

One of the biggest innovations Bitcoin brings to the world is a way to conduct commerce without the need to trust other human beings.  By passing 50% (one could argue even 40% is too much), ghash.io changes this equation and now requires that we trust the person(s) running them -- whoever they are.  Apologists for ghash.io claim that it is not in their best interest to do anything to compromise the network, but it does not take much imagination to see that there are many scenarios in which this supposed conflict of interest does not prevent malicious mischief from taking place.  This flies in the face of everything that Bitcoin once stood for.

I believe I read recently that some of the core developers (including Gavin) are of the belief that there are no proactive measures they can take (as developers) to effectively stop a 51% attack and must instead wait until it occurs before introducing defensive changes to the code.  While there may be many technical reasons which support such a viewpoint, this should not make anyone who is s stakeholder in Bitcoin feel confident.  One can only imagine the selling frenzy and resulting price drop when the first significant double spends are confirmed.  Bitcoin has enjoyed a first mover advantage since the first altcoins appeared on the scene many years ago, but this is exactly the sort of thing that could erode its lead.

There are other ways to mitigate the problem.  One that has been already tried but appears to be ineffective is to appeal to the community to move their mining power to other pools.  Certainly there are other measures which I haven't seen discussed yet.  In the past, I have seen pools, even large ones, shut down for days at a time by large DDOS attacks.  Perhaps watching their mining revenue drop to near-zero for a couple of days might influence the owners of ghash.io to modify their ways.  Billions of dollars of market value are potentially at stake here compared with a much smaller loss in revenue for ghash.io of they are forced to limit themselves to less than 40% of mining.

What's their business model if they charge 0% ?

This. So much this.

Anyone who overlook what happens today is oblivious. It's a very serious problem.

We should see CEX.IO's statement and see what they are going to do.
Depending on how that unravels, it wouldn't be a bad idea to DDoS.

Yes, if it's not an impending catastrophe, then at the very least it's certainly a bad precedent and not the direction we want to go.

In 2012 Gavin suggested a solution to 51%, but that's probably a move towards centralization.

http://gavintech.blogspot.de/2012/05/neutralizing-51-attack.html

We need other players in mining business to cut down their profit to stay afloat.

They have CEX, where "investors" who apparently can't do math will buy mining shares for twice their NPV.

This will be ready soon?
The plan sounds like a real, lasting, "peaceful" solution.  :)

They could redirect anytime they want.

Ultimately if a single entity control the hashpower, it is centralization.

Here's another potentially likely GHash scenario:

• GHash sells most of its available bitcoins for fiat
• GHash achieves 51+% on purpose knowing it will trigger a selloff
• GHash buys back the bitcoins at a greatly reduced price
• GHash points its miners to other pools to alleviate the threat
• Bitcoin price rises again and GHash realizes a large profit from market manipulation

This seems like a low-risk strategy, generates a tidy profit for GHash, and can probably be done several times before the community catches on so long as they wait long enough between runups.

If you believe that they are so beneficent that they would never try anything like this, then perhaps you'd like to buy some shares I have in the Golden Gate bridge for sale?

But DDoSing or Booting a service wouldn't really call anything in our favor. Bitcoin and other cryptos have a special feature, one that many currencies don't have. People aren't denied to mine, or have it. Nobody can confiscate it.

If we DDoS CEX/GHash just because they're mining, and yes, they might be getting close to 51%, that's still not a excuse to say, "Yeah. They're getting close to doing something dangerous. Let's make a exception." Because if that was the case, I don't think Bitcoin would be were it is now.

That's highly misleading, a pool that solves more blocks, has lower variance, and miners LOVE low variance. Because a small pool that has high variance can possibly not solve any block for several days, and then difficulty may go up at this point, and you essentially has lost money.

btw, it's completely pointless to rally against GHash.io, since it charges 0 fee and provides good service, eventually all miners will flock to it, as any miner that does not use GHash.io is essentially losing money and will lose the mining competition. The only option is to build another pool with good service and 0 fee, and rely on community donations for operation cost.

We are not talking about denying anyone the ability to mine here.  We are talking about ways the community can proactively take action in order to reduce the risk of another market crash.  Arguing that taking an action which some people might consider unethical in response to a credible threat to billions of dollars of market capitalization just to protect the interest of a few, mostly anonymous individuals at GHash.io doesn't make any business sense at all.  The community has already appealed to GHash.io to voluntarily restrict their mining (as did BTCGuild before them) in order to avoid going over 40%.  They made their intentions very clear by their actions and so it is time to consider other options.

If you are worried about high variance and loosing money start using PPS pools like polmine or eligius, nice and steady income.

Can u plz explain this high variance thing in simple term ? What does it mean ?

Exactly. You can't just trust them. Who are they? Nobody knows who's behind CEX and GHash.
We could and should react if they keep doing this.

I just found one behind CEX.IO. Jeffrey Smith, Chief Information Officer at CEX.IO => http://uk.linkedin.com/pub/jeffrey-smith/30/76b/ba3

He's just their public relations person.

Public relations person will know the employer... right ? We need the missing link.

Detailed Discussion: https://bitcointalk.org/index.php?topic=647561.0

Why don't you just email him then? :D
You won't find out the owners that easily. Not unless they step out of the shadow.

I'm still surprised that they are holding this much hashrate. What are the miners thinking? If a 51% happens, all their trouble will be worth nothing.

I'll just add this here: http://www.reddit.com/r/Bitcoin/comments/27lotn/people_dont_realize_how_serious_a_50_attack_is/

People do realize, but a sudden unjustified change may paralyze the system.

Well it's hardly surprising. Miners are there for the profit and given that Cex offers the highest return with its 0% fee and reasonably good probability of solving blocks for lower variance they will simply move there because of greed. Nothing is going to happen until we get some form of backlash as people will simply just continuing mining like this thinking that since nothing has happened till now nothing will happen which may not be in fact the case.

I would like to say miners aren't stupid but perhaps they are all greedy and want to use a 0% pool that reveals the most blocks
That said it is a problem and I guess the miners think ignorance is bliss

Every miner including GHASH.IO should run distributed P2POOL and make it more than 70% of network hashing power to solve this problem permanently, I think that will be the major task for miners in the coming years

I also think that bitcoin foundation have the responsibility to advertise the use of P2POOL at large scale

This is the solution to centralized mining:

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


Join us and create a decentralized cryptocurrency instead of one that will be controlled by a few big corporations. Myriad is still before the first halving so it's definitely not too late!

Dont try to lure people to some Shitcoin. People discussing 51% are not newbie and are well aware the shitcoin's pump & dump schemes. At every problem of bitcoin, u people jump in to encash the opportunity, but u failed, fail and will continue to fail to dethrone the undisputed king of crypto currency.

No this is not a solution. This is an alternative coin. I'll rather stick with Bitcoin.
Try suggesting something that can be implemented into Bitcoin.  ;)

Bouncing from 42 to 38 and back it appears like they are hopping or someone with some big hashing is.

Has anything bad happened with this? I've been out of the loop for a week or so. I read a 51% attack could be pretty devastating.

just fud which in itself can be bad.

The truth is that there is no fix to bitcoin that will solve this problem, as seen in this thread and the other 1000 that also take up this issue.

I believe bitcoin will be the leader either way, but it will eventually be controlled by a few people meaning it will not decentralized - like it or not, that's the truth.




Exactly like this..

Nothing will be done to solve the issue because the people who decide don't want to 'fix' it (nothing is broken in their pov)




Even one the bitcoin devs can see where this is going..
https://bitcointalk.org/index.php?topic=651056.0


I don't understand how people cannot take this seriously.. having more than 50% is a disaster, anything even close to 40% is bad.

GHash.IO achieved 51% of the total n/w hash power, as u'll find in the first page of this thread, but they did not attack the n/w. They simply switched off some their machines to show good faith to the community and no attack took place. Now, will we trust them or not is an altogether different question.

Yeah, I don't quite get why they don't do this already......

When will miners figure out they are losing profits by mining at Ghash. Seems pretty obvious it's effecting the btc price.

Why will they ? It is free market buddy. Decentralization needs to be controlled at protocol level. U cant expect another human to act for your benefit, while doing business.

It amazes me they worry about "dust" ddos so they micromanage that but won't do anything
let alone address the issue of a pool taking over more than half the networks hashing.
At this rate the datacenters will become the new central banks.
BTC will be relegated to the history books.

PS: ghash isn't making the price decline, it was declining before this issue popped back up.
It might not be helping it get back into the 600's but w/e

Price is declining probably because the US is going to dump the Silk Road coins at some market in next few week + Dish n/w is dumping their earning to pay liabilities in FIAT.

p.s. Big traders know, even if GHash.IO reached 50%+, they wont do anything at least now to allow double spend.

So you undestand this much.

Yet you think that there will somehow just appear a magical solution that will fix all the centralization problems with bitcoin?

It has been discussed for years and there is no easy fix - that's why people are looking into alternatives. And ontop of that it will just become more difficult to change anything with the bitcoin protocol the longer it goes.

agree
I don't think they would do anything like that but if they could capture over 60% they could indeed manipulate the market
their way.

Yes, I understand this and I also understand how an open source project works. Most of the shit coins are launched by people to make quick profit by pump & dump. After Bitcoin, there is only one true innovation in the crypto world, i.e. Ethereum.

Anyways, coming to the point, there are already 2 suggested solutions to counter 51%...

1. Getblocktemplate (https://en.bitcoin.it/wiki/Getblocktemplate)

2. Neutralizing a 51% attack by Gavin (http://gavintech.blogspot.de/2012/05/neutralizing-51-attack.html)

wow they just dropped down to 24 ph/s
If that was all them from 24 to 44 ph/s that is a lot of power in one place.

They said Ghash is 45% their ASIC and 55% independent miners.

one of only 2 pools with 0% fee, as well as including miner fees

the only pool who offers an all-in package of both cloud mining and personal mining. As well as having an exchange for the cloud mining.

One of the few pools who offers merged mining on multiple coins.

Offers APIs and a clear overview of your hashrate and mined coins at any time

Offers not only automatic cashout but also automatic cashout split between multiple addresses (which no other pool offers, and is really handy when you share a physical miner and don't want to split the earnings manualy all the time)

And why you don't trust your central bank ?

To be honest, I'm afraid that GHash is a well-made ponzi scheme.

Here in the topic, I read that miners joining GHash are only serving their own good which is the only reasonable thing to do.

Let's take a closer look at that statement.

- trying to maximize their profit, miners join GHash instead of another pool.

- GHash exceeds 51% hashing power.

- panic ensues and price of BTC goes down and therefore profits of the miners get lowered.

This short elaboration shows that miners joining GHash are actually not serving their best interest. There exists a math explanation for this. https://www.youtube.com/watch?v=2d_dtTZQyUM


So to really serve their best interest, miners should voluntarily distribute themselves between several quality pools so that none of the pools can reach 51%.

If in this case the Nash equilibrium can be achieved with spread of information and voluntary decisions, good. Otherwise the bitcoin protocol will need to be somehow adjusted, I think.

Here is a little modification of your process to show how the profit is actually made...

- trying to maximize their profit, miners join GHash instead of another pool.

- GHash exceeds 51% hashing power.

- panic ensues and price of BTC goes down and therefore profits of the miners get lowered. and they buy more from the market.

- GHash.IO stops some their mining machine to get down to 30%.

- Market rises again and they book all the profit.


p.s. ...and anyone can ride this tide. This is how traders make profit more than miners w/o investing in mining, but by analysing the fact & figures with proper logic.

I could be wrong but I don't think they will do it. A serious company (which, I imagine, GHash is) wouldn't trade its long-term prospects (which are closely connected to public loss of trust) for some short-term profit.

Besides, big strains to make bitcoin volatile are harming towards it. By making its price stable, its value would rise much faster (I guess some volatility would remain), than by making it volatile. And who the fuck needs to manipulate the price of BTC when all you have to do is buy and HODL anyway?

Unless they steal someones coins ala gox'd I seriously doubt the community at large would care that much.
greed is the drive in this community.

When we will move to P2P pools?

Dont blame the bitcoin community. Greed is the driving factor of the homo-sapience community.

not blaming anyone. Just opining my perspective .

That's a little worrying that a 51%attack is so easy..

Reaching 51% hash power and making the attack is different like having nuclear bomb and dropping it on a country.

Just checked this out to see what ghash.io's network % is ( see https://blockchain.info/pools?timespan=24hrs )


is it really 32% now or does it just say such cause it is getting DDOS attacks

thanks

Searing

Its at 30% now and i hope it stays that way for a long time.

Time to change the title to ~32%, please promote accuracy instead of (intentional?) FUD.  :)

GHash.IO has dropped down to 33%,actually,the time of standing above 50% is very short.
 no worry about the 51% attack.

They should go below 30% and then the crisis is averted. As long as they don't point the miners to "unknown".

No worry ....if u think Bitcoin is a bubble. But for us, who think Bitcoin is here for the long term to fight out the current monetary system, this is a weakness to be dealt with. DeepBit & GHash.IO are the 2 that have reached 51% till date, but no attack has taken place. DeepBit has gone to oblivion and probably one day GHash.IO will vanish too. But a new player will emerge and 51% will need to be addressed.

The biggest concern is that someone makes a service so efficient that everyone will flock to it
Gigahash was the closest by far by acting both as an exchange and a location for coins to be mined in addition offering different pool choices besides bitcoin and offering lower fees are a great combination.

That said it brings about the risk of an exchange and security crashing if everyone flocks to the network
A different approach such as Proof Of Stake acts as incentive to avoid a 50% attack but as Bitcoin is just proof of script we will always need to be concerned about a network hitting 51% concentration.

That and the decreasing number of full nodes as ASIC mining becomes centralized and the people who use full nodes to relay the block chain independently and decentralization of nodes starts to decrease.

These are concerns that I think Bitcoin has not addressed well and will need to find solutions to while we still have time to modify and adapt the system...

That or we will need to as a community one day accept a centralized mint in terms of hashrate and a few major nodes run by major mining companies that maintain the network due to the increasing size of the Blockchain and transactions.

The bolden part gives me the idea of how internet was initially designed and how it got under the control of ISPs.