I'm reaching out to share the following which may be of interest:

Last year, OONI wrote a research paper ("Measuring DoT/DoH Blocking Using OONI Probe: A Preliminary Study") which was presented at the Network and Distributed System Security Symposium (NDSS'21) as part of the DNS Privacy Workshop. You can read this paper here: https://www.ndss-symposium.org/wp-content/uploads/dnspriv21-02-paper.pdf

This study involves an investigation of encrypted DNS (DoT & DoH) blocking in Kazakhstan, Iran, and China with a new OONI Probe experiment (DNSCheck). 

Today, we're publishing a blog post with a summary of findings (and video presentation): https://ooni.org/post/2022-doh-dot-paper-dnsprivacy21/ 

You can also find a summary of findings through this Twitter thread: https://twitter.com/OpenObservatory/status/1537764247442268161

You can help contribute measurements on encrypted DNS blocking by running OONI Probe: https://ooni.org/install 

Thanks,

Maria.