THE INTERNET, EXPLAINED
Practical, independent writing on DNS, HTTPS, networks and the tools behind modern websites.
NETWORKS · 4 MIN READ
Before a browser can load a page, it needs an IP address. DNS resolvers turn memorable hostnames into addresses and cache answers for a limited period called TTL.
Changes to DNS records are not necessarily instant: cached answers may persist until their TTL expires. Check the authoritative answer and the resolver your device actually uses.
WEB SECURITY · 3 MIN READ
HTTPS uses TLS to encrypt data in transit and authenticate the server's certificate. This protects against many network-level attempts to read or change the data exchanged with a website.
A valid certificate does not mean the information on a site is trustworthy. It establishes a secure connection to the named endpoint.
OPERATIONS · 3 MIN READ
Start with name resolution, then network access, then the application. Check the A or AAAA record, test whether the destination port accepts connections, and inspect the web server's response.
Separating DNS, TCP, TLS and HTTP failures narrows down the problem without unnecessary changes to a working system.