Smart Card for Cryptographic Key Distribution

Eduardo Miguel Arez Claudino

Key information

Authors:

Eduardo Miguel Arez Claudino (Eduardo Miguel Arez Claudino)

Supervisors:

Ricardo Jorge Fernandes Chaves (Ricardo Jorge Fernandes Chaves); Alberto Manuel Ramos da Cunha (Alberto Manuel Ramos da Cunha)

Published in

October 29, 2024

Abstract

This thesis proposes and implements a secure key distribution system supported on smart cards, aiming to address the challenge of securely transferring cryptographic keys between physically distinct locations. Secure key distribution is a critical part of cryptographic systems, as the security of the system depends on the security of the distribution process. Traditional internet-based key distribution solutions, though convenient, expose the system to a large attack surface, inherent to online communication. By employing secure physical transportation, this work strives to reduce the attack surface, as intercepting the keys would require physical access to the medium used. This is achieved by using a secure smart card as the physical medium where keys are loaded for transportation. The main contributions of this work include the design of a key distribution system and the functional implementation of this solution across multiple layers: application, middleware, and applet. The applet is the software that is loaded on the smart card, which is responsible for protecting the keys while in transit. Smart cards were chosen as the physical transport medium due to their programmability, security features, and wide availability. Additionally, the thesis provides guidance for future developers, including a Java Card applet development guide and detailed Javadoc documentation, which can aid in the further extension of the system. The results demonstrate that the system is both functional and practical, achieving the key distribution goal while meeting the security requirements under various scenarios.