Opening a web page feels instant, but a chain of steps happens in a fraction of a second. Knowing the chain shows you where speed is won or lost and which part your hosting controls.
The journey, step by step
- You enter a URL such as
https://example.com/shop. - DNS lookup: the browser finds the server's IP address, usually from a cache. See how DNS resolution works.
- Connection: the browser opens a connection to the server, over TCP (HTTP/1.1 and HTTP/2) or QUIC (HTTP/3).
- TLS handshake: browser and server agree on encryption and the browser checks the SSL certificate. See SSL/TLS and HTTPS explained.
- HTTP request: the browser asks for
/shop, sending headers and cookies. - Server work: the web server checks its cache. On a cache hit it returns the stored page at once. Otherwise it hands the request to PHP, which runs the application code, queries the database and builds the HTML.
- Response: the server sends the HTML, compressed with Brotli or gzip.
- More requests: the browser reads the HTML and fetches CSS, JavaScript, fonts and images, many in parallel over the same connection.
- Rendering: the browser builds the layout and paints the page; scripts make it interactive.
Where time is spent
| Stage | What helps |
|---|---|
| DNS and connection | Fast DNS, a server location near your visitors (latency), HTTP/3. |
| Server processing (time to first byte) | Page caching, a fast web server like LiteSpeed, NVMe storage, up-to-date PHP, enough CPU and memory. |
| Downloading assets | Optimised images, fewer and smaller scripts, browser caching, a CDN. |
| Rendering | Lean themes, deferred JavaScript, stable layouts. |
What your hosting controls
The host is responsible for the server side: network, web server, storage, PHP versions and server-level caching. MdmHost uses LiteSpeed with NVMe storage, which pairs with the LiteSpeed Cache plugin for WordPress. The front end (theme, images, scripts) is up to the site itself.
Next steps
- LiteSpeed web server explained
- Speed up WordPress
- Choose a server location