Definition ∞ Sponge functions are a class of cryptographic primitives that process input data of arbitrary length to produce output of a desired length. They operate by “absorbing” input blocks into a fixed-size internal state and then “squeezing” out output blocks from that state. This construction allows them to serve as versatile building blocks for various cryptographic applications, including hash functions, stream ciphers, and message authentication codes. Their security relies on the underlying permutation function and the rate at which data is absorbed and squeezed.
Context ∞ In blockchain technology and digital assets, sponge functions, notably Keccak (SHA-3), are critical components for hashing data, generating addresses, and ensuring transaction integrity. Their efficiency and robust security properties make them suitable for resource-constrained environments and protocols requiring verifiable computation. Ongoing research focuses on developing new sponge constructions optimized for zero-knowledge proofs and other advanced cryptographic schemes within decentralized systems.