Parallelization Attack

Definition ∞ A parallelization attack is a method by which an adversary attempts to speed up a computationally intensive task by distributing it across multiple processors or machines. In cryptographic contexts, this attack aims to reduce the time required to solve a problem that is designed to be sequentially slow. It directly challenges the time-lock properties of certain cryptographic primitives.
Context ∞ Parallelization attacks are a specific concern for cryptographic schemes like Verifiable Delay Functions (VDFs), which are designed to be inherently sequential. If a VDF can be significantly sped up through parallel computation, its core security property of a fixed time delay is compromised. Defenses against such attacks involve designing VDFs with algebraic structures that resist parallel speed-ups.