On August 7th, ETH Co-founder Vitalik Buterin has proposed a new kind of consensus algorithm which requires control over 99% of nodes to carry out an attack. Vitalik called it as "observer nodes" and with the implementation of this idea, ETH can become the most secure public blockchain in the world. With this consensus algorithm, 51% attack can be the thing of past!
How it works:The new algorithm introduces a new kind of validator nodes called as the “independent observer nodes”. These nodes observe the chain in real-time and detect inconsistencies in when the message appears. This works because, Double Spend attacks are slightly quicker (or slower) compared to normal transactions, and the special nodes in Vitalik’s solution detect just that.
Ethereum developer
Conrad Barski further explains,
“Usually, all blockchain consensus[algorithms] care about is what the validators (i.e. miners) of a chain do. Vitalik is proposing that if an independent observer of the network traffic (i.e. just the blockchain client a user is running, not a miner/validator) watches what’s happening in real time and pays attention to when messages appear, they can detect ‘foul play’ by miners performing a 51% attack and this can provide additional safety guarantees that can protect against such an attack. This is similar to this is somewhat similar to how merchants are already checking for 51% attacks themselves, only Vitalik’s version is more large-scale and complex“
Link to Vitalik's paper: https://vitalik.ca/general/2018/08/07/99_fault_tolerant.htmlNews Source: https://blockmanity.com/news/ethereum/vitaliks-new-consensus-algorithm-make-51-attack-obsolete-requires-99-nodes-attack/Vitalik has always been my favorite guy in the world of Blockchain. Even though the paper is fairly complex and didn't yet understand it completely. But this algorithm has the capability to change the ETH blockchain into the most secure public blockchain in the world. It is just a proposal and implementation has not yet decided.