Security Implications of Network Address Translation on Intrusion Detection and Prevention Systems

Network address translation (NAT) is a technology that allows multiple computers on a LAN to share a single public IP address for accessing the Internet. Without it, the IPv4 protocol´s limited number of available addresses would be pushed to its limits. However, NAT poses a big problem for security and especially for networks protected by intrusion detection systems (IDS) and intrusion prevention systems (IPS). The paper underlines the NAT´s implications on IDS and IPS and proposes a solution that includes the NAT technique in this security infrastructure.