~snip~
My point is any amount of mining power can't control how many coins they generated per block, spend other people's coins, reversing any transaction. thus there is none of 100% control. You are excluding nodes within the decentralization aspects.~
51% of mining power can control any and every aspect of blockchain with PoW concept.
Nodes are nothing.
No.
Let's pull up snipped information from the Bitcoin wiki:
Quote from: https://en.bitcoin.it/wiki/Majority_attack
Majority attack
If the attacker controls more than half of the network hashrate, this has a probability of 100% to succeed. Since the attacker can generate blocks faster than the rest of the network, he can simply persevere with his private fork until it becomes longer than the branch built by the honest network, from whatever disadvantage.
If the attacker controls more than half of the network hashrate, this has a probability of 100% to succeed. Since the attacker can generate blocks faster than the rest of the network, he can simply persevere with his private fork until it becomes longer than the branch built by the honest network, from whatever disadvantage.
Attacker has a lot of computing power
An attacker that controls more than 50% of the network's computing power can, for the time that he is in control, exclude and modify the ordering of transactions. This allows him to:
Reverse transactions that he sends while he's in control. This has the potential to double-spend transactions that previously had already been seen in the block chain, affecting all coins that share a history with the reversed transaction
Reverse confirmations for any transaction that had previously been seen in the block chain while he’s in control.
Prevent some or all transactions from gaining any confirmations
Prevent some or all other miners from mining any valid blocks
The attacker can't:
Reverse other people's transactions without their cooperation (unless their coin history has been affected by a double-spend)
Prevent transactions from being sent at all (they'll show as 0/unconfirmed)
Change the number of coins generated per block
Create coins out of thin air
Send coins that never belonged to him
~
Probably the most likely scenario where this attack would be employed would be for a government to try to get control over Bitcoin by acquiring a majority of hashing power (either directly or by enforcing rules on private miners within its borders). Then this government could use the transaction-censorship power listed above to do things like:
Prevent any transactions spending "stolen" coins, effectively destroying those coins. If the coins clearly are stolen, then there is a risk that this action will be accepted by the Bitcoin community, but this would set a very damaging precedent. If it becomes possible for coins to be blacklisted in this way, then it is a slippery slope toward blacklisting of other "suspicious" coins.
Prevent all transactions from unknown people, so everyone has to register with the government in order to transact.
An attacker that controls more than 50% of the network's computing power can, for the time that he is in control, exclude and modify the ordering of transactions. This allows him to:
Reverse transactions that he sends while he's in control. This has the potential to double-spend transactions that previously had already been seen in the block chain, affecting all coins that share a history with the reversed transaction
Reverse confirmations for any transaction that had previously been seen in the block chain while he’s in control.
Prevent some or all transactions from gaining any confirmations
Prevent some or all other miners from mining any valid blocks
The attacker can't:
Reverse other people's transactions without their cooperation (unless their coin history has been affected by a double-spend)
Prevent transactions from being sent at all (they'll show as 0/unconfirmed)
Change the number of coins generated per block
Create coins out of thin air
Send coins that never belonged to him
~
Probably the most likely scenario where this attack would be employed would be for a government to try to get control over Bitcoin by acquiring a majority of hashing power (either directly or by enforcing rules on private miners within its borders). Then this government could use the transaction-censorship power listed above to do things like:
Prevent any transactions spending "stolen" coins, effectively destroying those coins. If the coins clearly are stolen, then there is a risk that this action will be accepted by the Bitcoin community, but this would set a very damaging precedent. If it becomes possible for coins to be blacklisted in this way, then it is a slippery slope toward blacklisting of other "suspicious" coins.
Prevent all transactions from unknown people, so everyone has to register with the government in order to transact.
What do you think nodes are doing within the Bitcoin network? I supposed you think it has zero influence within the network?
Controlling any and every aspect of bitcoin is incorrect. See the point that attacker can't do as the above quoted message. The attacker surely can do those things, but all of the honest nodes will reject it since it does not adhere to the rules.
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