Ethereum: What is the equivalent of the “51% attack” wave?
The concept of controlling most network nodes or hash power in cryptocurrency can have devastating effects on the safety and stability of the block chain. Two notable examples are the “51%” “” attack by Bitcoin and Ethereum’s own implementation, which we will explore to understand what this means for decentralized networks.
Bitcoin: The 51% attack
In Bitcoin, a miner gains control when it has at least 50% of the total hash power in the network. This allows them to execute a double expense attack, where they try to spend the same amount twice in a single transaction without any previous agreement of others. This is done by controlling more than half of the computational resources of the miners.
If a miner gains control over more than 50% of the Power of the hash, it can:
- Block new blocks if there are less than two valid blocks before one.
- Spend coins that were not extracted in those first blocks, creating “double expense” attacks.
- Create false or forged transactions without any prior agreement.
The Ethereum equivalent: the threshold of 51% and the role of intelligent contracts
In Ethereum, the equivalent concept is a hard bifurcation, where a change in the rules of the protocol requires a certain threshold (in this case, around 50%) of the validators (miners) according to its implementation. However, unlike Bitcoin, Ethereum uses intelligent contracts.
A 51% threshold in Ethereum means that for any given blocking, at least 50% of the validators of the network must give their consent for its execution. This allows the attacker to control the majority of the computational power of the network and execute malicious transactions without being detected.
This vulnerability is more complex than the 51% attack of Bitcoin due to the decentralized architecture of Ethereum and the use of intelligent contracts. Smart contracts are self -jecution programs that automatically enforce certain rules, which makes it difficult for an attacker to exploit this weakness through traditional means such as double expense attacks.
Security implications
Both Bitcoin and Ethereum’s hard forks pose significant security risks. A 51% attack can lead to:
- Loss of trust: If a malicious actor gains control over the network, users can lose faith in the protocol.
- Financial instability: The sudden loss of control could interrupt the economic dynamics of the entire network.
- Increased vulnerability: once an attacker gains control, he can potentially execute arbitrary transactions, including those that do not have a previous agreement.
Mitigating risks
To minimize these risks, developers and users must be aware of possible vulnerabilities and take measures to protect their systems:
- Network Security : Regularly update software and accessories, use safe passwords and enable two factors authentication.
- Intelligent contract safety : Implement solid tests and monitoring for intelligent contracts, and consider the use of libraries or safe frames.
- Decentralized applications (DAPPS) : Be careful when you use DAPPs that store user funds or have a complex logic.
In conclusion, the concept of a 51% attack on the hard fork of Bitcoin and Ethereum serves as a reminder of the importance of network safety and decentralized architecture. While both examples highlight the potential risks associated with the control of most nodes or the power of the hash, understanding these concepts can help users take measures to protect their systems and guarantee the stability of the blockchain ecosystem.
