What is 51 Percent Attack? A 51 percent attack is an attack on a blockchain by a group of miners who control more than 50% of the network's mining hash rate. Let's take a closer look.
What is 51 Percent Attack?
A 51% attack is the term given to a cryptocurrency blockchain attack carried out by a group of miners who collectively account for more than 50% of the network's mining hash rate. The controlling parties have the ability to change the blockchain because they control 51% of the network's nodes.
By preventing new transactions from receiving confirmations, the attackers would be able to stop payments between some or all users. Additionally, they would have the ability to undo activities that were taken while they were in control. Reversing transactions would enable them-spend to do coins, which is one of the problems that proof-of-work consensus systems were intended to prevent.
How Can You Prevent a 51% Attack?
There are numerous potential protections against 51% attacks. One is changing the blockchain's underlying approval algorithm from PoW to delegated proof-of-stake (DPoS). DPoS uses multiple delegates that change over time to validate each new block. In a DPoS blockchain, 51% of attackers must control both hashrate and the delegates, making attacks more difficult and unlikely.
Another alternative is the use of Modified Exponential Subjective Scoring (MESS). Block reorganizations are analyzed by MESS, and ratings are given to show how trustworthy the reorganization is. The majority of 51% attacks are driven by large-scale reorganizations, which MESS views as fundamentally untrustworthy.
Today, ETC uses MESS to protect its network from 51 percent attacks. According to ETC, a 2020 attack that required only a $3,800 computer to initiate would now cost approximately $20 million.
By using delayed transaction approvals and fines to deter miners who seem to be preparing an attack, some currencies, such Horizen and Komodo, are protected against 51% attacks.
What is 51 Percent Attack? How Can You Prevent a 51% Attack? - Hopefully, this article can help you to get some knowledge.
