The website is the Stanford Internet Research Data Repository, which provides a public archive of research datasets related to hosts, services, websites, and the internet. It is hosted by the Stanford Empirical Security Research Group but welcomes data from other researchers as well. The site offers a restricted noncommercial JSON interface for accessing data and encourages contacting them with any questions. They host two external datasets: Censys Universal IPv4 Internet dataset includes daily snapshots of public IPv4 hosts and their associated services, while the Censys Universal Certificate dataset contains x509 certificates found in public certificate transparency logs on the internet.
