Short Integer Solution

Definition ∞ The Short Integer Solution (SIS) problem is a fundamental computational problem in lattice-based cryptography, which forms the basis for constructing various cryptographic primitives. It involves finding a non-zero integer vector of small length that, when multiplied by a given matrix, results in a zero vector modulo a certain integer. The presumed difficulty of solving the SIS problem is a cornerstone for the security of many post-quantum cryptographic schemes. This problem is considered hard even for quantum computers.
Context ∞ In discussions surrounding post-quantum cryptography and the security of digital assets, the Short Integer Solution problem is a key concept. News reports about new quantum-resistant signature schemes or encryption methods often refer to the SIS problem or related lattice problems as their underlying security foundation. Understanding the hardness of SIS is essential for evaluating the robustness of cryptographic systems designed to protect blockchain transactions and digital communications from future computational advances.