syn | syn-ack | ack
👤 clickity-clacks FQDN into a web browser on a computer 🖥️
🖥️ checks local hosts file 🗂️ not found ❌
🖥️ checks local DNS cache 🗂️ not found ❌
🖥️ makes DNS request to DNS resolver 🌐
🌐 checks local DNS cache 🗂️ not found ❌
🌐 is a lazy non-recursive DNS resolver
🌐 tells 🖥️ “do your own work, buddy!”
🖥️ makes DNS request to root DNS server 🌍
🌍 replies with authoritative DNS info 📜
🖥️ makes DNS request to the authoritative DNS server 🏢
🏢 replies with IP address 🔢
🖥️ opens TCP connection (SYN) to 🔢
🔢 replies TCP (SYN/ACK) to 🖥️
🖥️ replies TCP (ACK) to 🔢
THREE-WAY HANDSHAKE completed 🤝
🖥️ sends HTTP request to 🔢
🔢 replies with HTTP response to 🖥️
WEB PAGE DISPLAYED ✅