Packet to Prompt
Follow a request across the network one step at a time: start by opening a website at home, then follow a question to an AI at work.
Your request starts inside your home. The laptop joins the Wi-Fi, finds the router, looks up the website's number, and the router sends the request out under the one address your whole house shares.
The laptop joins the Wi-Fi
Before anything else, the laptop joins your Wi-Fi. It proves it knows the password without ever sending it, and the two sides agree a fresh secret key. From then on, everything sent over the air is scrambled.
Like a secret knock at the door that also hands both of you a new code word for the conversation inside.
Show the technical detail
Done by Home Wi-Fi access point, WPA3-Personal. Layers 1 and 2: the radio is the physical layer, and association and its keys belong to 802.11, the data link. Nothing above it exists yet.
| Field | Before | After |
|---|---|---|
Link stateBeyond | not associated | associated to SSID HomeNet (changed at this hop) |
Pairwise session keyBeyond | (none) | derived by the four-way handshake (changed at this hop) |
Data frames on the airBeyond | (none yet) | encrypted with CCMP-128 (changed at this hop) |
wlan0: STA 3c:22:fb:1a:2b:3c WPA: pairwise key handshake completed (RSN)
The access point logs which device joined and when, and nothing about what it then does. On WPA2-Personal, anyone who knows the Wi-Fi password and records this handshake can decrypt the session afterwards; WPA3 SAE closes that, because each session key cannot be rebuilt from the password and a recording.
Test yourself with one question
What does the four-way handshake give this laptop?