Privacy Gateway: a privacy preserving proxy built on Internet standards

Privacy Gateway is a service that relays encrypted HTTP requests and responses between a client and application server, improving end-user privacy by preventing the server from seeing sensitive information like IP addresses and TLS fingerprints. It is based on Oblivious HTTP (OHTTP), an emerging IETF standard built upon standard hybrid public-key cryptography. Deployed for Flo Health Inc., Privacy Gateway encrypts all request data, preventing the application server from seeing users' IP addresses and Cloudflare from seeing the contents of that request data. It enables applications to collect user telemetry in a privacy-respecting manner and allows users to visit healthcare sites without worrying about their IP address being tracked.