TLS 1.3 on the Wire: What an Eavesdropper Can Still See Before Encryption Kicks In

Originally published at https://blog.pathvector.dev/protocol-lab-tls-09/ — part of the free Protocol Lab series.

This post is part of Protocol Lab, a free, hands-on series for learning networking protocols by building and breaking them in a container lab. All the lab material — topologies, configs, and scripts — lives in the repo: github.com/pathvector-studio/protocol-lab.

TCP gave us a reliable byte stream. TLS runs on top of it to add encryption and server authentication. This lab opens one TLS 1.3 connection and asks a precise question: what can an on-path observer see before encryption takes over?

Reading guide: rfc-notes/tls-handshake-certificates.md

Prerequisite: TCP Lab 07: One Connection, From SYN to FIN

TLS 1.3 on the Wire: What an Eavesdropper Can Still See Before Encryption Kicks In

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