Is a consensus algorithm in which the probability of obtaining the right to validate a block depends on the share of the network’s computing performance owned by the node. The algorithm is one of the earliest and most widespread, it underlies the Bitcoin network. Nodes are not required to provide opinions before a consensus is reached. Instead, the nodes use the hash function on the block repeatedly, changing one of its elements (NonCE field) in order to fulfill a certain condition, for example, so that the hash sum of the block begins with a certain number of zeros. The algorithm by which the Bitcoin mining network comes to a consensus, determining which of the mining nodes will write the formed block to the blockchain. PoW boils down to two main points:
- The need to perform a certain rather complex and time-consuming computational task
- Possibilities to quickly and easily check the result