Understanding the Performance and Challenges of DNS Query Name Minimization

As a promising solution to DNS privacy, query name minimization limits the unnecessary leakage of query name information in DNS requests. Due to the lack of detailed measurement study, there is little understanding of the performance, compatibility, and security implications of query name minimization. In this paper, we measure the performance of query name minimization. We find that query name minimization requires a significant query increase but NXDOMAIN optimization technique can alleviate the increase. We propose a DDoS vulnerability with query name minimization and evaluate its impacts and defenses using NXDOMAIN optimization. Broken empty non-terminals are measured and identified as the critical obstacles to the transition to query name minimization.