New lattice-based protocols for proving correctness of a shuffle

In an electronic voting procedure, mixing networks are used to ensure anonymity of the casted votes. Each node of the network re-encrypts the input and randomly permutes it in a process named shuffle, and must prove that the process was applied honestly. State-of-the-art classical proofs achieve log...

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Detalles Bibliográficos
Autor: Sánchez Torrón, Manuel
Tipo de recurso: tesis de maestría
Fecha de publicación:2020
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/328091
Acceso en línea:https://hdl.handle.net/2117/328091
Access Level:acceso abierto
Palabra clave:Algorithms
Electronic voting
Lattice-based cryptography
RLWE-encryption
Zero-knowledge proofs
Arithmetic circuit satis
Fiability
Benes permutation networks
Proof of a shuffle
Algorismes
Classificació AMS::68 Computer science::68W Algorithms
Àrees temàtiques de la UPC::Matemàtiques i estadística
Descripción
Sumario:In an electronic voting procedure, mixing networks are used to ensure anonymity of the casted votes. Each node of the network re-encrypts the input and randomly permutes it in a process named shuffle, and must prove that the process was applied honestly. State-of-the-art classical proofs achieve logarithmic communication complexity on N (the number of votes to be shuffled) but they are based on assumptions which are weak against quantum computers. To maintain security in a post-quantum scenario, new proofs are based on different mathematical assumptions, such as lattice-based problems. Nonetheless, the best lattice-based protocols to ensure verifiable shuffling have linear communication complexity on N. In this thesis we propose the first sub-linear post-quantum proof for the correctness of a shuffe, for which we have mainly used two ideas: arithmetic circuit satisfiability and Benes networks to model a permutation of N elements.