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Protocols

A visual, animation-first tour of the wire protocols that hold the internet together. Every protocol page is built from the same three interactive pieces — so once you know how to read one, you can read them all:

Zoomable packet diagram
The classic field "rectangles". Any box marked has sub-fields — click it to zoom in, use the breadcrumb to zoom back out.
Handshake animation
Step or play through the message exchange between the two endpoints. The 🔒 boundary shows exactly where traffic becomes encrypted.
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Decoders
Break a dense token (like a cipher suite) into its meaningful parts, one hover at a time.

Protocols

Ready SSL / TLS The record layer, the handshake, cipher suites, TLS 1.2 vs 1.3, and session resumption / 0-RTT. SoonTCPSegments, the 3-way handshake, sliding window, teardown. SoonIPIPv4 / IPv6 headers, fragmentation, addressing. SoonUDPThe minimal datagram header. Ready DNS The message format, the recursive resolution walk, record types, and transport (UDP/TCP/DoH). SoonQUICPackets, 0-RTT, streams over UDP.