Block Confirmation
Ledger Security, Transaction Finality
Block Confirmation refers to the process by which a new block is added to a blockchain and subsequently accepted by the network. Each additional block appended on top of it serves as a “confirmation,” making it exponentially more difficult to reverse or reorganize previous transactions. More confirmations mean higher security, as it would require greater computational power or control to tamper with the ledger. Block confirmations are critical in determining when transactions become irreversible and fully trusted.
Use Case: On Bitcoin, merchants often wait for 1–6 block confirmations before considering a transaction settled. With each new block added, the risk of reversal or double-spending drops dramatically.
Key Concepts:
- Irreversibility — More confirmations increase the probability that a transaction cannot be changed or undone.
- Settlement Finality — The point at which transactions are considered permanent due to sufficient confirmations.
- Consensus Mechanism — Protocol by which blocks are proposed, validated, and confirmed by the network.
- Validator Node — Node that participates in validating and confirming new blocks.
Summary: Block confirmation is the foundation of blockchain security. The more confirmations a transaction has, the more secure and final it becomes, enabling trust in digital money and decentralized systems.