ActiveDNS: Is There Room for DNS Optimization Beyond CDNs?

Domain Name System (DNS) converts domain names into IP addresses. The specific IP it returns to a client has significant implications for optimizing user experiences on web services. The establishment of Content Distribution Networks (CDNs) facilitates the spread of content across diverse cache servers, thereby enabling quick responses to user requests. But not all distributed Internet services have sufficient budget or resources to deploy CDN servers. For these services, is there a cost-efficient way to enhance users’ access experience to them? In this paper, we build a data-driven DNS resolver system named ActiveDNS. We conduct a historical analysis of billions of DNS request-response logs from a public DNS resolver. Inspired by these findings, we probed dozens of public DNS servers to obtain available IPs behind carefully selected target domain names and measure their performance metrics. We built a domain ip performance database of 2.9 million records that can be easily incorporated into the open-source DNS framework BIND via DLZ technology. ActiveDNS has been deployed in real-world scenarios and the evaluations reveal promising results. Compared to currently used DNS resolver, the 75th service round-trip time (RTT) for the IP returned by ActiveDNS decreased from 67 ms to 43 ms.