@inproceedings{13551df0d7314274a561f2f81047f604,
title = "Zero-Knowledge for Homomorphic Key-Value Commitments with Applications to Privacy-Preserving Ledgers",
abstract = "Commitments to key-value maps (or, authenticated dictionaries) are an important building block in cryptographic applications, including cryptocurrencies and distributed file systems. In this work we study short commitments to key-value maps with two additional properties: double-hiding (both keys and values should be hidden) and homomorphism (we should be able to combine two commitments to obtain one that is the “sum” of their key-value openings). Furthermore, we require these commitments to be short and to support efficient transparent zero-knowledge arguments (i.e., without a trusted setup). As our main contribution, we show how to construct commitments with the properties above as well as efficient zero-knowledge arguments over them. We additionally discuss a range of practical optimizations that can be carried out depending on the application domain. Finally, we formally describe a specific application of commitments to key-value maps to scalable anonymous ledgers. We show how to extend QuisQuis (Fauzi et al. ASIACRYPT 2019). This results in an efficient, confidential multi-type system with a state whose size is independent of the number of transactions.",
keywords = "Commitments, Key-Value map, Zero-knowledge",
author = "Matteo Campanelli and Felix Engelmann and Claudio Orlandi",
year = "2022",
doi = "10.1007/978-3-031-14791-3_33",
language = "English",
isbn = "978-3-031-14790-6",
series = "Lecture Notes in Computer Science",
publisher = "Springer",
pages = "761--784",
editor = "Galdi, {Clemente } and Jarecki, {Stanislaw }",
booktitle = "Security and Cryptography for Networks",
address = "Netherlands",
note = "13th International Conference on Security and Cryptography for Networks, SCN 2022 ; Conference date: 12-09-2022 Through 14-09-2022",
}