Design and Security Analysis of SDN-Based IoT-Oriented Blockchain Protected E-Voting System

The electoral system is one of the fundamental pillars of democracy, but the traditional voting system suffers from several limitations such as fraud voting, vote tampering, impersonation, and inefficiencies. To overcome these limitations, several research works have been initiated to design a blockchain-based e-voting system. These designs addressed the loopholes of the existing ones to a limited extent. Here, a novel multi-level blockchain-secured SDN-based IoT enabled e-voting system has been proposed. The proposed system consists of booth, district, state, and country level systems. Here, a voter needs to be authenticated at the booth-level and then this valid vote data can be propagated to the upper hierarchical levels and stored there after signing and encrypting it using ECDSA and ECC respectively. Man-in-the-middle attacks, DoS/DDoS, unauthorized access, and impersonation attacks are avoided using flow rules in SDN controllers and firewalls installed in the servers. Furthermore, blockchain technology provides security for voting data stored at all levels. The security strengths were tested at different levels (e.g., programming, operating system, and network level) using open-source tools (i.e. scyther, nmap, metasploit, etc.). The performance of the proposed architecture was evaluated satisfactorily in a testbed. It also performed satisfactorily under both normal and stressed conditions in a scaled-up environment.