Consensus mechanisms: what they are

Consensus mechanisms are the methods used in a decentralized system to reach agreement on the state of the system and to verify transactions. These mechanisms are critical to the operation and security of decentralized distributed ledgers, such as the blockchain.

Consensus mechanisms solve the double-spending problem and ensure that the transactions made on the system are valid and secure. Different consensus mechanisms offer different ways of reaching this agreement, and each has its own advantages and limitations.

The two main types of consensus mechanisms are Proof of Work (PoW) and Proof of Stake (PoS). PoW is the mechanism used by Bitcoin, while PoS is a newer mechanism used by other cryptocurrencies, such as Ethereum.

The Proof of Work (PoW) mechanism relies on solving a computational problem that requires a lot of computing power from "miners" to verify transactions. Miners compete to solve the problem, and the first to solve it earns the right to add a new block to the blockchain and receive a reward in cryptocurrency.

The Proof of Stake (PoS) mechanism works differently. In this mechanism, transaction validators are chosen based on how much cryptocurrency they hold. The more cryptocurrency someone holds, the greater their chance of being chosen as a validator and confirming transactions.

Consensus mechanisms play a critical role in the security, resilience and scalability of decentralized systems. Each mechanism has its own advantages and its own challenges. Choosing the right consensus mechanism depends on the system's requirements and goals.

Note: the text above is a simple introduction to consensus mechanisms and doesn't cover every detail and variant that exists. In upcoming articles we'll look at more consensus mechanisms.