Performance Evaluation of Secure and Privacy-preserving DNS at the 5G Edge

With the improved network performance and efficiency, 5G has been a very appealing alternative for various applications and devices, including but not limited to Industrial IoT (IIoT) applications. However, since IIoT applications require real-time transmission guarantees for time-critical data, optimizing the 5G network performance has attracted much research recently by pushing critical services to the 5G edge. One of such services is Domain Name System (DNS) which is typically offered by ISPs to serve 5G networks. However, due to its heavy role on Internet traffic, DNS has seen many attacks in the past in terms of its authenticity of records and exposure of user requests. Therefore, there have been many variants of DNS protocol such as DNSSEC and DNS over TLS (DoT) to address these security and privacy issues. As such these new protocols need to be integrated into 5G edge and their overhead should be investigated for their potential use in time-critical applications. In this paper, we consider deploying secure and privacy-preserving DNS to the 5G base stations and investigate the feasibility and performance of such an edge computing approach. To this end, we utilize SDN capabilities and forward packets to a local SDN controller for extracting and processing DNS queries. Thus, the DNS packets are served at the 5G edge with optional security and privacy features without being forwarded to remote ISP servers. Our approach is implemented in a virtualized 5G testbed network, and we present various DNS performance results via different metrics and scenarios.