Comparative Analysis of the DoT with HTTPS Certificate Ecosystems

The Internet’s Public Key Infrastructure (PKI) has been used to provide security to HTTPS and other protocols over the Internet. Such infrastructure began to be increasingly relied upon for DNS security. DNS-over-TLS (DoT) is one recent rising and prominent example, whereby DNS traffic between stub and recursive resolver gets transmitted over a TLS-secured session. The security research community has studied and improved security shortcomings in the web certificate ecosystem. DoT’s certificates, on the other hand, have not been investigated comprehensively. It is also unclear if DoT client-side tools (e.g., stub resolvers) enforce security properly as modern-day browsers and mail clients do for HTTPS and secure email. In this research, we compare the DoT and HTTPS certificate ecosystems. Preliminary results are so far promising, as they show that DoT appears to have benefited from the PKI security advancements that were mostly tailored to HTTPS.