260 Network basics [0.5d]

HTTP

• How do HTTP requests and responses look like? What are HTTP headers? What are they used for?
• Look at real-life HTTP exchanges:
  • Open makandra.com
  • Open the Network tab of your browser inspector.
  • Reload the page.
  • Inspect each request and look at its request headers, response headers and payloads.
• What is HTTP/2?

Digging deeper

• Use curl to save a copy of http://www.sueddeutsche.de/.
• Use curl to save the CSS stylesheet of sueddeutsche.de

SSL / TLS

• What is SSL / TLS?
• Why do we need it?
• How do SSL certificates work?
  • What is a "certificate authority"?
  • What's the significance of the "Common Name" entry in a SSL certificate?
  • What does "certificate chain" mean?
• Find out how you can see SSL info for this very website in your browser.
• Go to https://badssl.com/ Show archive.org snapshot . For a few of the broken SSL examples: See how your browser reacts. Try to understand what is wrong.

DNS

• What is DNS?
• What are A, AAAA, CNAME, MX entries?
• What are subdomains?
• Imagine an application that is running as https://www.moviedb2000.de. Now the project is renamed and should be moved to https://filmplexhq.com. Which steps are necessary to make this change? Are there any problems doing this?

Routing

• Use dig and traceroute to find out where www.makandra.com is physically located.
• What way does a package take when you request www.makandra.com from inside our offices? Actually name the physical places the bits visit during their trip.