2026-04-17T05:23:13Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/4222922025-07-22T19:13:20Zcom_2072_1033col_2072_452951

Evaluating a mixnet based on threshold cryptography regarding its resilience-cost trade-off Pérez I Castillo, òscar Àrees temàtiques de la UPC::Informàtica::Seguretat informàtica::Criptografia Data encryption (Computer science) mixnet cryptography Xifratge (Informàtica) Implementation of a mix based on threshold cryptography and evaluation of efficiency as well as improved resilience when composed into a mixnet A mix network (mixnet) is a type of anonymous communication network that aims to enable its users to send messages anonymously to each other in the presence of a global network adversary. Mixnets are composed of mixes arranged in different topologies, which prevent correlating the input and output of messages by altering and reordering the flux of messages. However, they are vulnerable to a static adversary being able to compromise a full path of mixes that a message takes through. We introduce and evaluate a new approach for the core building block the of mixnet, the mixnode. By replacing each mixnode by a cluster of mixnodes and by the usage of threshold cryptography we are able to reduce compromise probabilities by between 50% and 99% with minor additional cryptographic overhead due to the additional cryptographic operations and a maximum x10 decrease in the throughput of each mixnode. The work includes a compromise security analysis for designing this new building block, building blocks implementing cryptographic operations and a proof of concept model evaluating throughput and latency parameters. 2024-05-21 Master thesis S'autoritza la difusió de l'obra mitjançant la llicència Creative Commons o similar 'Reconeixement-NoComercial- SenseObraDerivada' Open Access Universitat Politècnica de Catalunya