Sensitivity Analysis of Random Port Hopping

Although DoS (Denial of Service) attacks making the amount of network traffic increase excessively are threats to availability of communication services in our internet society, the complete prevention and avoidance are impossible because the conventional ways such as fire wall and packet filtering are still infeasible and incomplete. The random port hopping (RPH) by Badishi {it{et al.}} (2005, 2007) provides a robust communication protocol to decentralize influences by malicious attacks and to realize an exact packet filtering with light load. Since the utility and limitation of RPH against general DoS attack patterns are not clear, however, it has not been used yet as the standard communication protocol in the real world. In this paper, we carry out the simulation study and take place the sensitivity analysis of RPH in terms of the communication success rate. After pointing out a drawback of the existing RPH, we also propose a fine-grained RPH algorithm for more general DoS attack patterns.