Block Depth Confirmation

Block depth confirmation is the practice of waiting for a specific number of subsequent blocks to be added to the chain before considering a transaction as settled. This waiting period is a defensive measure against the risk of chain reorganizations, as the probability of an attacker successfully rewriting a block decreases exponentially with each additional block.

The required depth depends on the security model and consensus speed of the specific blockchain. In financial contexts, deeper confirmation requirements provide higher security but increase the time required for settlement, creating a trade-off between speed and safety for high-value transactions.