Weighted Threshold Encryption with Silent Setup

Guru-Vamsi Policharla

Paper 2026/2148

Weighted Threshold Encryption with Silent Setup

Guru-Vamsi Policharla, Commonware, Inc.

Abstract

We construct the first non-trivial weighted threshold encryption scheme with silent setup. The CRS and each public key consists of O(W) group elements, where W is the maximum committee weight. Both the weight assignments and the threshold for decryption can be dynamically chosen at encryption time. Each partial decryption is a single G1 element computed non-interactively with one scalar multiplication, independent of the party's weight. The CPA ciphertext is two G_1 elements, improving upon the shortest known unweighted scheme, and CCA security costs two additional field elements. We prove security in the generic bilinear group model.

Metadata

Available format(s): PDF
Category: Cryptographic protocols
Publication info: Preprint.
Keywords: Silent Setup Batched Threshold Encryption Weighted
Contact author(s): guruvamsi policharla @ gmail com
History: 2026-09-22: approved; 2026-09-22: received; See all versions
Short URL: https://ia.cr/2026/2148
License: CC BY

BibTeX

@misc{cryptoeprint:2026/2148,
      author = {Guru-Vamsi Policharla},
      title = {Weighted Threshold Encryption with Silent Setup},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/2148},
      year = {2026},
      url = {https://eprint.iacr.org/2026/2148}
}