At Gerus-lab, we build systems for clients across Web3, AI, and SaaS — and a recurring theme in our infrastructure conversations is network reliability in restricted environments . Recently, a piece of research from the Russian internet community caught our attention: a full technical teardown of how whitelist-based internet filtering actually works at the packet level. We read it. We rebuilt the mental model. And we thought the western dev community needed to hear this. Because this isn't just a Russia story. It's a playbook that authoritarian governments worldwide are copying — and understanding it makes you a better infrastructure engineer anywhere. The Shift From Blacklists to Whitelists Classic internet censorship runs on blacklists : a list of forbidden domains (YouTube, Twitter, etc.), everything else passes. It's reactive, easy to bypass with a VPN, and constantly playing whack-a-mole with new proxies. Whitelists flip the model entirely: Everything is blocked by default.…