Majority is not enough_ bitcoin mining is vulnerable _ springerlink online currency like bitcoin

• 32 citations

• 2 mentions

• 436 readers

• 5.2k downloads

Part of the

Lecture notes in computer science

Book series (LNCS, volume 8437) abstract

The bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security rests critically on the distributed protocol that maintains the blockchain, run by participants called miners. Conventional wisdom asserts that the mining protocol is incentive-compatible and secure against colluding minority groups, that is, it incentivizes miners to follow the protocol as prescribed.

We show that the bitcoin mining protocol is not incentive-compatible. We present an attack with which colluding miners obtain a revenue larger than their fair share. This attack can have significant consequences for bitcoin: rational miners will prefer to join the selfish miners, and the colluding group will increase in size until it becomes a majority.Online currency like bitcoin

at this point, the bitcoin system ceases to be a decentralized currency.

Unless certain assumptions are made, selfish mining may be feasible for any group size of colluding miners. We propose a practical modification to the bitcoin protocol that protects bitcoin in the general case. It prohibits selfish mining by pools that command less than \(1/4\) of the resources. This threshold is lower than the wrongly assumed \(1/2\) bound, but better than the current reality where a group of any size can compromise the system.

• 32 citations

• 2 mentions

• 436 readers

• 5.2k downloads

Part of the

Lecture notes in computer science

Book series (LNCS, volume 8437) abstract

The bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security rests critically on the distributed protocol that maintains the blockchain, run by participants called miners.Online currency like bitcoin conventional wisdom asserts that the mining protocol is incentive-compatible and secure against colluding minority groups, that is, it incentivizes miners to follow the protocol as prescribed.

We show that the bitcoin mining protocol is not incentive-compatible. We present an attack with which colluding miners obtain a revenue larger than their fair share. This attack can have significant consequences for bitcoin: rational miners will prefer to join the selfish miners, and the colluding group will increase in size until it becomes a majority. At this point, the bitcoin system ceases to be a decentralized currency.

Unless certain assumptions are made, selfish mining may be feasible for any group size of colluding miners. We propose a practical modification to the bitcoin protocol that protects bitcoin in the general case.Online currency like bitcoin it prohibits selfish mining by pools that command less than \(1/4\) of the resources. This threshold is lower than the wrongly assumed \(1/2\) bound, but better than the current reality where a group of any size can compromise the system.

• 32 citations

• 2 mentions

• 436 readers

• 5.7k downloads

Part of the

Lecture notes in computer science

Book series (LNCS, volume 8437) abstract

The bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security rests critically on the distributed protocol that maintains the blockchain, run by participants called miners. Conventional wisdom asserts that the mining protocol is incentive-compatible and secure against colluding minority groups, that is, it incentivizes miners to follow the protocol as prescribed.

We show that the bitcoin mining protocol is not incentive-compatible.Online currency like bitcoin we present an attack with which colluding miners obtain a revenue larger than their fair share. This attack can have significant consequences for bitcoin: rational miners will prefer to join the selfish miners, and the colluding group will increase in size until it becomes a majority. At this point, the bitcoin system ceases to be a decentralized currency.

Unless certain assumptions are made, selfish mining may be feasible for any group size of colluding miners. We propose a practical modification to the bitcoin protocol that protects bitcoin in the general case. It prohibits selfish mining by pools that command less than \(1/4\) of the resources. This threshold is lower than the wrongly assumed \(1/2\) bound, but better than the current reality where a group of any size can compromise the system.Online currency like bitcoin

• 32 citations

• 2 mentions

• 436 readers

• 5.7k downloads

Part of the

Lecture notes in computer science

Book series (LNCS, volume 8437) abstract

The bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security rests critically on the distributed protocol that maintains the blockchain, run by participants called miners. Conventional wisdom asserts that the mining protocol is incentive-compatible and secure against colluding minority groups, that is, it incentivizes miners to follow the protocol as prescribed.

We show that the bitcoin mining protocol is not incentive-compatible. We present an attack with which colluding miners obtain a revenue larger than their fair share. This attack can have significant consequences for bitcoin: rational miners will prefer to join the selfish miners, and the colluding group will increase in size until it becomes a majority.Online currency like bitcoin at this point, the bitcoin system ceases to be a decentralized currency.

Unless certain assumptions are made, selfish mining may be feasible for any group size of colluding miners. We propose a practical modification to the bitcoin protocol that protects bitcoin in the general case. It prohibits selfish mining by pools that command less than \(1/4\) of the resources. This threshold is lower than the wrongly assumed \(1/2\) bound, but better than the current reality where a group of any size can compromise the system.