Keep names and addresses separate
A name is a durable label. An address is one answer about where to try a connection. Treating them as separate observations makes a problem easier to describe.
The complete index
Notes
Seven readings about what a connection can tell us, and what still needs a separate check.
Names and identity provide a starting point. Latency, layers and caches explain why similar requests can produce different observations. The final two notes help keep a small investigation clear and proportionate.
What a verified connection tells you
A certificate check connects a secure session to the requested name. The page returned inside that session still deserves its own review.
Delay and throughput answer different questions
A quick first reply and a fast transfer describe different parts of an experience. A single number cannot stand in for both.
Read a failure one layer at a time
A connection can fail before a name is resolved, during a secure handshake or after a request arrives. Naming the layer narrows the next check.
Why a refresh can show an older page
A browser may reuse stored content instead of transferring it again. A refresh is therefore an observation about both the website and the browser's local state.
Give a small page a small request budget
The work of opening a page includes its supporting files. A useful page can remain rich in explanation while asking the network to do very little.
Leave a connection check easy to repeat
A short record of the question, conditions and result is usually more reusable than a large collection of unexplained output.