None of the concepts you listed are really specifically "networking" related. Yes, they all tend to use the network, but aside from ssl/tls, are all methods of

None of the concepts you listed are really specifically "networking" related. Yes, they all tend to use the network, but aside from ssl/tls, are all methods of communication to achieve X. TLS is a wrapper for these comms methods, which provides a layer of security. Have you tried doing more than just reading/watching videos? You can learn all 4 of these concepts in one go, if you were to stand up a server, and then configure each of the concepts you want to learn, by hand. You can learn DNS by setting up your own DNS server, and setting up a zone, entries, etc. Once thats working, use the server to stand up a webserver (nginx/apache), and install something into it (lots of cool selfhosted webapps around). Now that you have a working webserver and app, you can start setting up TLS/SSL. Rather than using LetsEncrypt, learn the (sadly, pretty terrible) ways of setting up your own CA and certs, by hand, with something like openssl. Now that you have certs, with your own CA, you can install that cert on your webserver, and youve now completed 3/4 of the concepts you wanted to learn. You can pick apart each one of these as you work through the task, for example, learning the various HTTP headers, and what they do, by use of an webapp that has an API on your webserver. As for tcp/ip; imagine youre obsessed with shaking hands, and you work in an environment where you have to repeat everything you hear as its done. > Hello i am CableNinja < Hello cableninja > I would like to begin talking now < ok you talk now > ok, heres what im saying about X < ok i got your thing about X > ok cool thanks < thanks > bye < bye! And thats basically tcp. UDP on the otherhand.. > Hey this a joke about UDP, and i dont care if you get it < (joke received, or not), i dont care. And thats the protocols in a nutshell. If you want reading material on any of these topics, id suggest their RFCs. They provide conceptual data, limitations, and in depth dives of how the sausage is made.