Distributed Helios - Mitigating Denial of Service Attacks in Online Voting

One of many major issues that plagues Internet voting is the potential for a distributed denial of service attack on the voting servers. These denial of service attacks are harmful because they block voting during the downtime. In addition, most current online voting protocols are centralized with only one voting server, making such an attack likely to disenfranchise some voters. The question is how to combat these attacks. One solution is to distribute the servers in a parallel manner, so in case one server goes down, the others can still provide service to voters. Whereas many online voting systems assume the constant availability of the voting infrastructure, we focus on the event that a server becomes unavailable. We extend a previously established online voting protocol, Helios, by adding multiserver capability. These servers communicate using the Paxos protocol, an algorithm for fault tolerant distributed environments. An analysis of this solution concludes that a multi-server Helios network communicating through the Paxos protocol promises safety and robustness.