Networking Overview

Tutorials

code a TCP/IP stack

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

Non Routable IP Ranges

IP addresses that by default are not routed by domain-name servers.

127.0.0.1:       127.0.0.1                     # Available IPs: 1
10.0.0.0/8:      10.0.0.0 – 10.255.255.255     # Available IPs: 16,777,214
172.16.0.0/12:   172.16.0.0 – 172.31.255.255   # Available IPs: 1,048,574
192.168.0.0/16:  192.168.0.0 – 192.168.255.255 # Available IPs: 65,534

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