Development of an API for financial data exchange between multiple parties using homomorphic encryption

• Ano de defesa: 2025
• Autor(a) principal: Siqueira, Yaissa Campos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: CKKS; Criptografia homomórfica; Homomorphic encryption; Open banking
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/45/45134/tde-17062025-165647/

This work explores the use of homomorphic encryption to address privacy and security concerns in cloud-based financial applications, particularly within the context of Open Banking in Brazil. Motivated by the rise of cloud computing and the associated privacy risks, the study focuses on the CKKS homomorphic encryption scheme due to its ability to handle real numbers, a crucial feature for financial transactions. The paper provides a background on the mathematics underlying homomorphic encryption, including lattice-based cryptography and the Learning With Errors (LWE) problem. It then details the design and implementation of an API that leverages the CKKS scheme to enable secure and private transactions within an Open Banking app. The API allows users to manage multiple bank accounts and execute transactions through a single platform while ensuring data confidentiality. The performance of the API is analyzed, and its advantages and disadvantages are discussed. The research highlights the potential of homomorphic encryption to enhance privacy and security in the financial sector, paving the way for more secure and trustworthy data sharing practices in the era of Open Banking.