Distributed Trust Empowerment for Secure Offline Communications

Abstract

Most of today’s digital communications over the Internet rely on central entities, such as certificate authority servers, to provide secure and authenticated communication. In situations when the Internet is unavailable due to lack of reception in remote areas, natural disasters destroying network infrastructure, or congestion due to large amounts of traffic, these central entities may not be available. This causes secure communication, even among users in the vicinity of each other, to become a challenge. This paper contributes with a solution that enables peers within the vicinity to communicate securely without a connection to the Internet backbone. The solution operates on the Wi-Fi infrastructure mode and exploits a private distributed ledger to ensure a trusted authorization among users without a third party. Moreover, the solution enables users to set up secure communication channels using mutual authentication for exchanging data securely. Finally, the solution is validated through a proof of concept application and an extensive experimental study aiming at optimizing system parameters and investigating the performance of the application is conducted. The results from these measurements indicate that the solution performs well on small to medium-scale networks.