What is PoW and PoS?

In PoW blockchains, consensus is reached through computational proof of work, and the main goal is to prevent malicious actors from consuming or attacking the network in a dangerous way. This consensus method requires a large amount of computing power to create new blocks, but it is very simple for others to verify that work. This is why PoW is said to be an asymmetric strategy.

In PoS blockchains, the goal is the same, to create blocks and reach consensus, but in PoS, a power of processing is not as large as in PoW. On average, PoS consumes less than 1% of the energy of PoW. In PoS, miners are called validators. While in PoW, the one who gets the reward is the one who solves the mathematical puzzle first, in PoS, the validator who will win the reward is chosen randomly, but giving a greater probability to those who meet certain criteria. The Bitcoin community is very reluctant to PoS because it is easier to get a large amount of the currency in question than more than 51% of processing power. Therefore, PoS are more vulnerable in terms of security. But here each case is a case and it is necessary to analyze each currency.

PoW blockchains tend to be more decentralized while PoS are more centralized, not only in access, but also in operation. More than half of Ethereum validators are on Amazon's cloud. PoW blockchains present major challenges in operational scalability, often requiring second-layer (L2) solutions, while PoS have much more flexible scalability mechanisms. PoW algorithms are much simpler to implement than PoS and, therefore, less susceptible to errors. A good example is the PoS of Ethereum that was being implemented since 2018.