A quick overview of how the Web works, how the DNS works, and how our computers access and download websites.
- We use domains to access websites — but computers need IP addresses
- IP addresses are confusing for humans
IPv4 — 127.0.0.1
IPv6 — 2001:0db8:85a3:0000:0000:8a2e:0370:7334
(Domain Name System)
Maps Domains ⬌ IPs
Each registered domain has a bunch of information attached to it—here’s some important entries:
NS— The authoritative DNS information serverA— The domain to IP mapping for the hostMX— The email server locationCNAME— A subdomain or alias for the A record
- You type a domain into your browser—your computer needs the IP
- It contacts a DNS server asking for the the IP address of a domain
- The DNS returns the IP address to your computer (or forwards your computer to another DNS server)
- Your computer contacts the server located at the IP address directly and asks for the domain
- That server responds with an HTML page (or redirects your computer to another server)
- That HTML page triggers the browser render, downloads all the CSS, images, etc.
- Leasing a domain registers it in the DNS
- And points the domain to an IP address — the host
- Also points to where email is sent and received
Domain leases are not permanent—if you don’t renew on time you will lose the domain to a squatter.
Don’t buy your hosting, email & domains all from the same place!
- It may be convenient to start but will get really annoying
- Difficulty switching — if you want to change host, well, now you likely have to change all services
- Security — if one is compromised they all are