Preventing DNS Amplification Attacks Using the History of DNS Queries with SDN

Domain Name System (DNS) amplification attack is a sophisticated Distributed Denial of Service (DDoS) attack by sending a huge volume of DNS name lookup requests to open DNS servers with the source address spoofed as a victim host. However, from the point of view of an individual network resource such as DNS server and switch, it is not easy to mitigate such attacks because a distributed attack could be performed with multiple DNS servers and/or switches. To overcome this limitation, we propose a novel security framework using Software-Defined Networking (SDN) to store the history of DNS queries as an evidence to distinguish normal DNS responses from attack packets. Our evaluation results demonstrate that the network traffic for DNS amplification attack can completely be blocked under various network conditions without incurring a significant communication overhead.