Watson Jia will present his MSE talk "QUICstep: Circumventing QUIC-based Censorship" on Friday, April 28, 2023 at3pm in Sherrerd Hall 306. The members of his committee as as follows: Prateek Mittal (adviser) and Jonathan Mayer (reader) All are welcome to attend. Talk abstract follows below. Abstract: Governments around the world limit free and open communication on the Internet through censorship. To reliably identify and block access to certain web domains, censors inspect the plaintext TLS SNI field sent in TLS handshakes. With QUIC rapidly displacing TCP as the dominant transport-layer protocol on the web, censorship regimes have already begun prosecuting network traffic delivered over QUIC. With QUIC censorship poised to expand, censorship circumvention tools must similarly adapt. We present QUICstep, a censorship-resilient, application-agnostic, performant, and easy-to-implement approach to censorship circumvention in the QUIC era. QUICstep circumvents TLS SNI censorship by conducting a QUIC-TLS handshake over an encrypted tunnel to hide the SNI field from censors and performs connection migration to resume the QUIC session in plain sight of the censor. Our evaluation finds that QUICstep successfully establishes QUIC sessions in the presence of a proof-of-concept censor with minimal latency overhead.