What happens when a URL is entered into a browser? Describe the process from DNS query to page rendering.
sobes.tech AI
Answer from AI
When entering a URL in a browser, the following process occurs:
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Parsing the URL — the browser breaks down the entered address into parts (protocol, domain, path).
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DNS query — the browser contacts the DNS server to obtain the IP address of the domain.
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Establishing a TCP connection — the browser establishes a connection with the server via IP and port (usually 80 or 443).
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TLS handshake (if HTTPS) — a secure connection is established.
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Sending an HTTP request — the browser sends a request to the server (GET, POST, etc.).
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Receiving the HTTP response — the server returns data (HTML, CSS, JS, images).
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Processing the response — the browser starts parsing HTML, building the DOM.
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Requesting additional resources — the browser detects links to CSS, JS, images and requests them.
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Executing scripts and styling — the browser applies CSS, executes JS, which may modify the DOM.
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Rendering the page — the browser displays the content to the user.
This process may repeat during dynamic page updates or navigation.