Proof of Work: what is it?

the Proof of Work (PoW), also called Proof of Work in the language of Molière, describes a system that requires computing power from the service requester to access it and use it in order to discourage malicious use or attacks. This method was first theorized with a view to creating a system capable of preventing spam and denial of service attacks on the system, making it extremely resilient to threat common on the web. In 2004, Hal Finney adapted it so that it could be used in a fully digitized monetary system.

How does Proof of Work work?

The primary characteristic of this system is the asymmetry of the computational cost: the requestor must provide a considerable amount of computing power while the work carried out is easily verifiable by the recipient or a third party. In the context of cryptocurrencies, the Proof of Work is used to validate transactions and mine new tokens, key tasks that require a high level of security and that give a cryptocurrency its value, in whole or in part. Bitcoin was the first network to widely adopt the Proof of Work. Today, a majority of calculations are done through hash functions like SHA-256 which generates 256-bit character strings, and this is also the hashrate, the amount of strings generated over a given time, which defines the computing power of the processors and graphics cards in mining frame.

Criticisms and limitations of Proof of Work

On a large scale, the Proof of Work requires enormous computing power but guarantees the integrity of transactions without the need for a trusted third party, a bank in the current economic system, since the system becomes this third party. Due to its enormous need for energy, the Proof of Work is increasingly criticized for its environmental impact and several cryptocurrencies as Ethereum abandon it in favor of the Proof of Stake, while others like chia prefer him Proof of Space-Time that use storage space rather than computing power.