Fact does not help to make decision, because there are many facts regarding raising the block size and each of them have two sides: transaction capacity, network bandwidth requirement, block orphan rate, mempool size ... their importance are not the same because some of them would cause a fundamental change in the network's property, and each person have different opinion over the potential impact of the same fact

Many banks are still using their hardware/software developed during 90s, financial IT prefer no change over change, any kind of change can cause unpredictable risk. If there is any change, it should be as small as possible, and a very long period of follow up is a must. In this case, raise the block size to 2MB and observe it for at least 6 months is the typical approach in bank's IT strategy department


Currently spam transactions are those paying no fee and sending 1000 satoshi, at an extreme they could send 1 satoshi without fee, similar to satoshidice did in 2012, the amount of money required is neglictable. If you don't make a spam filter, even if you have 100MB block size, the spam will fill it in no time. But if you have an effective spam filter, you don't need to raise the block size yet

When banks are closed during weekend, no one panic. Similarly, when bitcoin network are being attacked by spammers, bitcoiners won't panic either. They will just wait until a new spam filter is published and apply it

The current problem is on the mempool, if the spam continues to build up, sooner or later all the memory on the nodes will be consumed, so a spam filter update is needed, it should be applied to majority of nodes to make the network resilient

Even the attack have some political implication, I don't think it will convince anybody to fork, a fork will just make the situation worse

Spammers can send millions of 0.0001 bitcoins without any fee to flood the mempool regardless of the blocksize. With a 20MB block, they will quickly raise the average block size to 20MB and heavily slowdown the network. On the contrary, it is safer to stay at current 1MB blocksize, so that spam can be analyzed thoroughly and dealt with

There are definitely lots of spam going on, these 0.00001 bitcoin transactions without fee happens quite often, don't know how did they managed to get into the blockchain. I remember that previous spam filter does not allow any transaction less then 5000 satoshi or something to be broadcasted

Exactly, there are many ways to spam the network, so there is no universal solutions, each type of spam can be identified through a pattern, and blocked through a protocol change, like anti virus /malware software update

Because majority of bitcoins are hoarded and used for large transactions, the spam will not impact too much, it will just reduce people's transaction frequency and increase the transacted amount each time (thus more fee is bearable). Only exchanges who do frequent transactions will be affected

At 7tps spam rate, 600K transactions per day will cost 60 btc at a fee of 0.0001 btc, that is $18000 at exchange rate of $300. even if the fee rise to 0.001 btc and blocksize increase to 10MB to make 70tps possible, that is $1.8 million, pocket change for banks. So if banks want to disable bitcoin, they can do it easily for a sustained period of time (FED can print 2.8 billion per day in QE). However, if bitcoin price rise another 10 times, fee rise to 0.01 btc and blocksize increase to 100MB, then banks need 1.8 billion per day to disable bitcoin, not practical any more, but then transaction will cost $30, just like an international wire, not suitable for small transactions any more

This could give legitimate users a choice to re-broadcast the transaction with higher fee or wait until another time. For attackers it does not matter since they are going to flood the network anyway

Again there is no universal solution against attacks. Chinese built a great wall, but the general that guarded the gate opened it for the enemy because of a woman

Reject high-frequency transactions from unknown source might be a better solution, but that means each node will be updated with a list for trusted high-frequency transaction entities, thus some kind of management scheme will be setup. Then there will be politics around who should or should not get into that list, will get complicated

Pure market driven solutions will not work due to some people who control large amount of resources will be able to attack for months while majority of users will not be able to compete with a higher fee. 1% of people having 99% of the resource is a fact

This test is very good on the live network, it showed us some interesting phenomenon and potential area to improve:

1. The cost for transaction is decided on the number of transactions, not how much bitcoin you send, so it will always benefit those who do large transactions, and people should do large transactions as much as possible, to make it economical

2. Larger blocksize like 20MB can not prevent this kind of attack/spam, it will just make it worse. Because carrying out such an attack is always feasible regardless of the blocksize: Spammers can send out 1 million transactions with very little fee, and the cost will be only 20x of this time, but the resulted congestion will be much more severe

3. Mempool will be overflow if the attacker just send millions of transactions, so there should be a mechanism to remove the transactions from the mempool if they are more than xx hours old

4. There is no universal solution to deal with the attack, it will be most efficient if the miners can find the source of the attack and block it, but if the attacker use a large network it will be very difficult to do that. Or, miners could register large exchanges (they typically have high transaction frequency), and only accept frequent transactions from those exchanges

The end of 2013, most risky time in bitcoin mining history, everything changed after the Chinese central bank announcement: Difficulty jumped and price crashed

The biggest problem is that price development is lackluster, if you could improve the exchange rate performance, make it rise 4x in a year, then the community will expand like supernova, all the other problem will be solved automatically 

I think Greece central bank indeed create euro, but not notes (I have noticed that each European country mint their own version of 1 euro and 2 euro coins, they are not the same look at different country. And they are inter-exchangeable: you can spend Spanish euro in France, etc...

But the question is still organizational: What makes Greece central bank listen to ECB's directive? Maybe they are from the same banking family? Or they have some kind of contract that Greece central bank must follow if they want to join EMU?

And to make a new currency value stable is very easy, just back it use gold and assets, and it usually works very well: People don't exchange gold with the new currency, they feel confident about the new currency when they CAN exchange gold with it

Put a large sell wall of 10000 coins at 270 and small buying order of 100 coins at 269, after a while you can collect some amount of panic coins

Pump the price and ddos the exchanges, and use stress testing to slowdown the blockchain, so that no sell pressure can reach exchanges in the planned pump period

People's psychology is very strange, if you pump up the price by 50%, many of them will sell, but if you pump up the price by 10x, many of them will think that something fundamentally changed. They will hold and hope for a even higher price. So once price reached 10x higher, you have plenty of time to cash out the coin, it will never quickly drop back to the start point, due to that human are adaptive, they will get used to the high price after a while and buy during each drop from that high. At mean time the mining becomes extremely profitable and more miners will be produced and sold, the difficulty also skyrocket

In fact Greece people never need euro to do domestic transactions, since all the transactions only happens in bank's database, no euro is really moved. Only when they export/import goods/services to other EU countries, their bank need to provide real euro, and even that could be set up by a clearing house if the export/import is balanced, only significant trade deficit will drain their euro quickly

It is quite complicated higher up there, what he said could mean totally different things, no one can easily understand how such a financial system works based on debt

But one thing is for sure, the world governments are not able to repay the loan due to less and less consumption in post IT era (more and more jobs will be replaced by automation and robots, thus the total spendable income of human will keep going down. They must either borrow more money to pay the debt or seek debt relief

At least two group of people won't change their stance: Austrian economic school supporters and libertarian

In fact many miners are still learning theories about money creation (What they do is money creation), and I think many of them will realize that limited supply is the only way for a consensus based, voluntarily participated currency to succeed. Without this property, bitcoin does not stand any chance before the competition of fiat money (If both currency are inflative, then most of the people would rather use FED's notes instead of a group of greedy miners' coin, at least FED's coin is backed by the US national debt )

I don't really understand the organization structure of EMU. Does Greece central bank have the right to create euro? Who controls greece central bank? Why couldn't Greece central bank print some Euro to repay their IMF and ECB loan???

This is a currency crisis, not a political one

When the money is controlled by banks, all the political debate is meaningless, because without money any kind of policy will not work at all. Greece government can order police to raid the bank and confiscate their cash, but they will find out that there is nothing in their vault, most of their assets are just numbers registered in foreign financial institutions  This way of banks protecting themselves against violent from politicians are invented by Rothschild family and still works well today

All the transactions in the country are in bank's database, and those are only numbers, no money involved. If the euro clearing system does not honor a transaction from the Greek banks, their bank account will be useless outside of Greece

What if Greek banks start to print euro? 50 billion a month?

Bitcoin essentially is a consensus, a protocol that people voluntarily follow. You can't really break a consensus since there is nothing to break, it is supported by every participants, not enforced by an authority or military force

In a centralized system, you could change the policy as you want if you are the commander. But in a decentralized system, the participants are connected by a similar interest and consensus, many people join bitcoin community because they prefer limited money supply. If some participants do not like this monetary policy, they can leave and mine their alt-coin with whatever policy they like

If some large mining farm fork the coin and increase the coin amount, they will generate a fork of bitcoin with unlimited money supply, they can even maintain that chain to have enough strong hashing power. However, they can't force people to use their chain, and their chain will be called something else and become useless for bitcoiners, and bitcoiners will still use the original chain

People might never understand what central bank is doing, but bitcoin is open source, even a line of code is changed, it will be examined by many developers. On internet, people won't be fooled like in fiat money system

The problem is not on the banks, it is the government officials who set up this anti-money laundering/terrorist financing, know your customer law and applied it to financial institutions like exchanges and banks (banks are essentially an exchange)

Regulators put a heavy fine on those institutions who does not follow this law. If anyone can trade bitcoin like buying grocery, there will be many criminals use bitcoin to launder money (money comes from hacked bank account, cheated victim, smuggling, drug dealing...), and once money enter bitcoin, it is not traceable anymore(at least beyond the current ability of law enforcement due to no regulatory framework at all on blockchain), so it is very difficult to reverse the loss like in fiat money system (In fact the law enforcements are more interested in reversing the loss, capture the criminal is less important since they never cease to exist)

So far the best practice is to treat it like cash, and limit each customers daily transaction volume like in an ATM

ECB is printing €60 billion per month, so it is a pocket change