Episode 121 - What happens when you type google.com into your browser address box and hit enter?
In this video I want to go through what really happens under the hood when you type google.com and you hit enter in a browser. This is inspired by alex’s github page below, it is a great detailed description of what happens. I did however add more details to certain areas and I removed some stuff like keyboard events and low level operating system like that. So if you are interested stay tuned! https://github.com/alex/what-happens-when 5:30 HSTS https://youtu.be/kYhMnw4aJTw 19:30 tcp vs udp https://youtu.be/qqRYkcta6IE 24:42 tls https://youtu.be/AlE5X1NlHgg 40:56 mimesniffing https://youtu.be/eq6R6dxRuiU Initial typing - lookup for most visited sites or an actual search Google.com Enter - parse is it a url or search term? If search do a search if url visit website Which protocol? which port ? HSTS? HTTPS or HTTP? DNS cached? Hosts? DoH? Lookup ? TCP ip / port ? arp? NAT? proxy? HTTP 1.1 ? More than one connection TLS version? ciphers? Alpn? SNI ? H2 ? H3? Quic? GET / - ? Headers compress cookies? binary stream? HTML? H2 push? HTML Parse? Make multiple requests css? JS? Multiple streams? If H1 then pipeline?