A supply cap is the maximum amount of an asset that a protocol is designed to allow. In a blockchain or digital asset system, this limit is enforced by the protocol rules, not by a promise from a company or administrator. The cap may be fixed from genesis or bounded by issuance logic, and every valid transaction must keep the asset total within that limit.
In cyber security, a supply cap matters because it protects monetary integrity. If attackers find a flaw in validation, consensus, or invariant checking, they may try to create tokens beyond the allowed amount, effectively “printing money.” Defenders look for impossible state changes, verify on-chain supply against protocol rules, and audit code paths that enforce issuance limits. A broken supply cap can damage trust in custody systems, exchanges, and any service that relies on ledger finality.