How Is ‘Nonce’ Used in the PoW Mining Process?
The nonce, or 'number only used once,' is a variable in the block header that miners iterate through to find a valid block hash. Miners repeatedly change the nonce and re-hash the block header data until the resulting hash meets the network's current difficulty target (e.g. starts with a certain number of zeros).
Finding the correct nonce is the "work" in Proof-of-Work, which proves the computational effort was expended.
Glossar
PoW Mining
Consensus ⎊ Proof-of-Work mining represents a decentralized computational process securing blockchain networks, fundamentally reliant on expending energy to validate transactions and create new blocks.
The Nonce
Variable ⎊ The Nonce is a variable data field included in the header of a Proof-of-Work (PoW) block, serving as the sole element miners are permitted to adjust during the computationally intensive mining process.
Block Header
Genesis ⎊ A block header, fundamentally, encapsulates metadata pertaining to a specific block within a blockchain; it serves as the block’s identifying signature and is critical for maintaining chain integrity.
Finding the Correct Nonce
Computation ⎊ Finding the correct nonce is the central computational task in Proof-of-Work consensus, requiring miners to repeatedly hash the block header with different nonce values until the resulting hash satisfies the network's difficulty requirement.
Difficulty Target
Constraint ⎊ The difficulty target is the numerical constraint that defines the required threshold for a valid block hash, directly controlling the rate of block discovery.