109.1 Fundamentals of internet

Tech Tutorial: 109.1 Fundamentals of Internet #

Introduction #

In the world of networking, a solid understanding of TCP/IP is crucial for any IT professional. TCP/IP, or Transmission Control Protocol/Internet Protocol, is the backbone of the internet and is essential for any networked communication. In this tutorial, we will delve into the fundamentals of TCP/IP network fundamentals, ensuring that you have a thorough understanding of how networking works in a Linux environment.

Key Knowledge Areas #

  • Understand the basics of TCP/IP
  • Subnets and routing
  • IPv4 and IPv6 differences
  • Common network utilities

Utilities #

  • ifconfig
  • ip
  • netstat
  • ss
  • ping
  • traceroute
  • dig
  • host

Step-by-Step Guide #

1. Understanding IP Addresses and Subnets #

An IP address is a unique address used to identify a device on a network. IP addresses are part of the broader concept of subnets which help divide the network into manageable pieces.

Example: Viewing and Setting IP Addresses #

  • Viewing IP Configuration with ifconfig:
ifconfig
  • Setting an IP Address with ifconfig:
sudo ifconfig eth0 192.168.1.10 netmask 255.255.255.0 up
  • Using ip command:
ip addr show

sudo ip addr add 192.168.1.10/24 dev eth0

2. Routing and Basic Network Configuration #

Routing is the process of selecting paths in a network along which to send network traffic.

Example: Viewing and Adding Routes #

  • View routes with ip:
ip route show
  • Add a new route:
sudo ip route add 192.168.2.0/24 via 192.168.1.1 dev eth0

3. Using Network Utilities #

These utilities help you diagnose and configure network settings.

ping - Check Connectivity #

ping google.com

traceroute - Trace Route to a Host #

traceroute google.com

netstat - Network Statistics #

netstat -ant

ss - Socket Statistics #

ss -tulwn

dig - DNS Lookup #

dig google.com

host - DNS Lookup #

host google.com

4. IPv4 vs IPv6 #

Understanding the differences between IPv4 and IPv6 is crucial as the internet transitions more towards IPv6 due to IPv4 address exhaustion.

Example: Displaying IPv6 Configuration #

  • Using ifconfig:
ifconfig eth0 inet6
  • Using ip:
ip -6 addr show

Conclusion #

Understanding the fundamental concepts of TCP/IP networking is essential for troubleshooting and managing networked systems. This guide has covered how to use various network utilities to monitor and configure networks. Mastery of these tools and concepts will enhance your ability to manage both small and large scale network environments effectively.

Ensure to practice these commands and utilize them in real network settings to get a hands-on understanding of how TCP/IP networking functions.