Decoy Analysis

Decoy analysis is the practice of evaluating the set of fake inputs or signatures used in privacy-preserving protocols to mask the true sender. In protocols that use ring signatures, the actual input is hidden among a set of decoys.

Decoy analysis involves examining the distribution, age, and characteristics of these decoys to determine which one is most likely to be the actual spender. This is a statistical game where analysts look for "leaks" in the privacy set caused by poor selection algorithms or user behavior.

If a user consistently selects decoys that are unlikely to be spent, they reduce their own anonymity set. This analysis is critical for understanding the true effectiveness of privacy protocols against sophisticated adversaries.