China’s Great Firewall is a frequently mentioned but often misunderstood system. It stands as one of the world’s most advanced and secretive censorship frameworks, influencing how over a billion individuals access the global internet. This system affects the development of privacy tools globally and is ever-changing, presenting challenges to researchers, developers, and policymakers.
Jackson Sippe, a PhD researcher at the University of Colorado Boulder, studies the functioning of national censorship systems. Recently, Jackson co-led a pioneering study on a previously undocumented technique of the Great Firewall, which disrupted encrypted proxy protocols in China for over a year.
In this episode, Jackson talks with Gregor Vand about the technical workings of the Great Firewall, the blocking event from 2021-2023, the reverse-engineered popcount-based detection algorithm, the ongoing battle of censorship evasion, and the implications of these discoveries for the future of an open internet.
Gregor Vand is a technologist focused on security, with experience as a CTO in fields like cybersecurity and software engineering. Based in Singapore, more about him can be found on his website or LinkedIn.
Read the transcript of this episode [here](http://softwareengineeringdaily.com/wp-content/uploads/2026/02/SED1892-Great-FIrewall.txt).
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