Welcome to the basics of networking! In this chapter, you'll learn the essential concepts and technologies that keep every network running. Networks are the backbone of modern IT, and understanding them is the key to more advanced topics.
Example of an IP address: 192.168.1.1
The OSI Model (Open Systems Interconnection) describes how data is transferred from an application on one computer to an application on another.
Layer | Description | Example |
---|---|---|
Application | Interaction with software | HTTP, SMTP |
Presentation | Data formatting, encryption | SSL/TLS |
Session | Session management between systems | API sessions |
Transport | Reliable data transfer | TCP, UDP |
Network | Routing of data | IP, ICMP |
Data Link | Error detection, framing | Ethernet, WLAN |
Physical | Physical connection (cables, signals) | Ethernet cables, Wi-Fi signal |
Checks if another device on the network is reachable.
ping 8.8.8.8
Shows the path of a data packet through the network.
traceroute example.com
Analyzes open connections and ports on a system.
netstat -tuln
A powerful tool for analyzing network traffic.
Now that you know the basics, the next chapter will focus on building and managing networks. Stay tuned!