What is Sybil Attack? How Blockchain protected against it?

What is Sybil Attack?

Sybil Attack is a type of attack performed on a network by creating multiple fake identities or accounts to control the network.

This attack is mostly performed on the blockchain systems by creating active multiple node identities at the same time in the network to gain the majority of power access of the network.

The aim of this attack is to perform illegal activities in the network by gaining the majority of influence.

As almost all blockchain systems are decentralized and work on voting or controlled by a majority of nodes identities, that’s why attackers start influencing the network by creating multiple identities on the network to get the majority of access on the network.

How Blockchain protected against it?

  • By using different consensus algorithms like proof of work (pow), proof of stack (pos) to prevent blockchain from Sybil attack.
  • Cost of creating identities is also a very popular way to avoid the creation of multiple identities which give rise to Sybil attack.
  • Allocate the different power to the different members where members with different power level have different reputation level.
  • Use the validation process for new members joining the network where already established honest members will validate the new joiners in the network.

Bitcoin Blockchain is using the proof of work consensus algorithms which is ultimately strong protection against the attacks such as Sybil attack.

But Ethereum Blockchain is migrated to Proof of Stack from Proof of Work consensus algorithms due to expensive mining consuming high energy of electricity.

Also Read: What is a Replay Attack? How Can Blockchains Be Protected Against These Attacks?