Original fictional timelines. No browser was used. No cache was measured.

Worked successful load
URL: http://note.lab.invalid/note
Scheme: http
Host: note.lab.invalid
Port: omitted, so 80 on this card
Path: /note

Order when nothing is reused from a cache
1. Read the URL.
2. DNS: resolve the host.
3. TCP: connect to the address and port.
4. HTTP: send GET /note.
5. HTTP: receive the response.
6. Render: the browser turns the response into the page.

A cache can skip a step that it can reuse. This card does not record a cache hit.
The later TCP-based HTTPS model inserts TLS after TCP and before HTTP.
HTTP/3 uses QUIC instead; this card models the TCP case.

Activity cards, uncached, in the order they were started
Card N: DNS name lookup, and this lookup fails
Card R: TCP connection, not started
Card Q: HTTP request and response, not started
Card P: render, not started

The failure stops the sequence at card N.
Check: the last started step is name.

Independent failure trace, separate from the activity
URL: http://shelf.lab.invalid/page
Uncached.
Name lookup: failed
TCP: not started
HTTP: not started
Render: not started