mediumConceptEntry
What happens when you type a URL and press Enter? Give me the version you would give in a campus viva, then tell me where you expect me to push.
Six steps in order: the browser checks its cache, DNS resolution turns the hostname into an IP address, a TCP handshake opens a connection, a TLS handshake authenticates the server and agrees keys, an HTTP request fetches the page, and the browser renders it. Panels push on DNS, the handshakes and certificates.
4 min readUpdated 2026-10-10Target archetype: Enterprise Captive
Answer
Short answer
It is six steps, each depending on the one before. The browser parses the URL and checks its cache. DNS resolution turns the hostname into an IP address. A TCP handshake opens a connection to port 443, a TLS handshake authenticates the server and agrees encryption keys, an HTTP request fetches the page, and the browser parses and renders it, fetching images, scripts and styles the same way.
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Likely follow-ups
- The DNS answer is cached. Name every place it could be cached between your browser and the authoritative server.
- Why would two packets not be enough to set up a TCP connection?
- Your laptop has the server's IP address. How does the first packet reach your router on the local network?
- What does the browser do if the certificate is valid but issued for a different hostname?
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