Enhanced User Authentication Based on Dynamic Port Knocking Technique

Abstract

Abstract—Port knocking is a passive authentication mechanism which aims to control firewall response using a sequence of connection attempts to its closed ports. Dynamic port knocking which varies in each session, faces many challenges which are knocking sequence synchronization between client and server, handling high load of normal requests, out of order knocks, lost knocks, knocking through NAT, and knocking attacks. In this paper, a proposed dynamic port knocking approach is provided. The proposed approach, with the help of intermediate IPS, enables client and target server to generate a unique dynamic knocking sequence based on a secured random seed. This process is executed only at first communication session. Next, client begins to authenticate himself by knocking the target service with different ports and different number of knocks each time a session is initiated. Client-Server knocking synchronization, lost knocks, and out of order knocks are considered for issuing a correct knocking. The proposed approach provides immunity against several network attacks such as DoS attack, replay attack, and brute forcing attack. Extensive simulation shows that the proposed work overcome other compared approaches in terms of response time, memory utilization, CPU utilization, and the number of provided features.