Ommer Block
Web3 / blockchain technology
An ommer block, also known as an "uncle block," is a valid block that was mined or validated but not included in the main canonical blockchain due to network latency or competing blocks being selected by the protocol. In Ethereum's original consensus mechanism, ommer blocks represented legitimate work by miners that was temporarily orphaned when another miner found a competing block at similar heights. Rather than completely discarding this work, Ethereum's protocol rewards ommer blocks with reduced ETH payouts and includes references to them in subsequent blocks. This incentive structure encourages network participation and reduces the advantage of large mining pools. Example: During Ethereum's proof-of-work era, when two miners simultaneously broadcast blocks at height 5,000,000, one would be selected for the canonical chain while the other became an ommer block. The miner of the ommer block would still receive approximately 87.5% of normal block rewards, plus the including block's miner would receive a small reward for referencing it. Why it matters for blockchain technology: Ommer blocks represent an elegant solution to network fairness, ensuring that legitimate mining work receives partial compensation even when orphaned. This mechanism reduces centralization pressure by making small mining operations more competitive with large pools.
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