Networking Overview

From wikinotes

Tutorials

code a TCP/IP stack https://www.saminiir.com/lets-code-tcp-ip-stack-1-ethernet-arp/

Basics

Information sent over a network is layered like an onion.
As you progress closer to your application, the outer layers are removed,
leaving only information that is useful to each stage.

<!-- a pseudocode piece of network data -->
<datalink>
  <network>
    <transport>
      <application/>
    </transport>
  </network>
</datalink>

5-layer TCP/IP model

- layer protocol unit address
1 physical 10 Base T, 802.11 Bits n/a
2 datalink Ethernet, WiFi Frames MAC addr
3 network IP Datagram IP addr
4 transport TCP, UDP Segment Ports
5 application HTTP, SMTP, .. Messages n/a