Verifiable Delay Function
A verifiable delay function is a mathematical function that requires a specific amount of sequential time to compute, but can be verified instantly by anyone. This is used in blockchain protocols to introduce randomness that is both unpredictable and fair, as no one can rush the computation to gain an advantage.
Because the time required is fixed, it prevents attackers from manipulating the outcome of a process, such as a lottery or derivative settlement. The verifiability ensures that the output is correct and was produced according to the protocol rules.
VDFs are a crucial tool for ensuring fairness in time-sensitive decentralized processes. They bridge the gap between deterministic code and the need for controlled, verifiable delays.
This is an advanced technique for creating robust, tamper-proof systems.