Hierarchical Threshold Structure-Preserving Signatures
18th International Conference on Computational Intelligence in Security for Information Systems, CISIS 2025, Salamanca, Spain, 16 - 17 October 2025, vol.2807 CCIS, pp.68-77, (Full Text)
- Publication Type: Conference Paper / Full Text
- Volume: 2807 CCIS
- Doi Number: 10.1007/978-3-032-19770-2_7
- City: Salamanca
- Country: Spain
- Page Numbers: pp.68-77
- Keywords: Hierarchical Secret Sharing Keys, Structure-Preserving Signatures, Threshold Signatures
- Middle East Technical University Affiliated: Yes
Abstract
We introduce a digital signature scheme that combines hierarchical secret sharing with threshold structure-preserving signatures. In this scheme, a global signing key is recursively partitioned into layers, each protected by its own threshold, so that distinct subsets of the same participant group can exercise role-specific signing authority. Hierarchical Threshold Structure-Preserving Signatures (HTSPS) distribute two SPS signing keys across a hierarchy by interpreting each user’s share as a polynomial-derivative value, so higher-level users hold evaluations and lower-level users hold higher-order derivatives; any group of participants that meets the vector of thresholds can interpolate to obtain a valid SPS signature, while sub-threshold sets see only random group elements. Our design composes Tassa’s Birkhoff-based share system with the threshold SPS yielding signature protocol with a multi-layered access structure.