Dishonest Majority

Definition ∞ A dishonest majority refers to a scenario in a distributed system where more than half of the participating nodes act maliciously. This concept is critical in understanding the security of consensus mechanisms, particularly in proof-of-work blockchains where it relates to a 51% attack. If a majority of computing power or staked assets is controlled by malicious actors, they can manipulate transactions or disrupt network integrity. Such an occurrence fundamentally compromises the trust and immutability of the blockchain.
Context ∞ The threat of a dishonest majority is a foundational security consideration in the design and analysis of decentralized networks. While often theoretical for large, established blockchains due to prohibitive costs, it remains a relevant concern for smaller networks or those with less distributed control. News occasionally reports on attempts or discussions surrounding 51% attacks, particularly following significant changes in network hash rate distribution. Ongoing research into alternative consensus mechanisms seeks to bolster resilience against such coordinated attacks.