How IPv4 Works – A Handbook for Developers

The Internet Protocol version 4 (IPv4) is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 is still the most widely deployed Internet protocol. Google’s IPv6 Statistics show...

Apr 30, 2025 - 21:30

How IPv4 Works – A Handbook for Developers

The Internet Protocol version 4 (IPv4) is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 is still the most widely deployed Internet protocol. Google’s IPv6 Statistics show 44.29% of traffic to Google services on April 24, 2025 is over IPv6, implying 55.71% goes over IPv4.

This handbook will take you through every aspect of IPv4, from understanding IP addresses to examining packet headers and fragmentation. You'll learn:

How IP addresses work and their different formats
Network addressing schemes from fixed-length to CIDR
Special IPv4 addresses and their uses
The structure and purpose of every field in the IPv4 header
How IPv4 handles packet fragmentation across different networks

Whether you're a network engineer, software developer, or IT professional, understanding IPv4 is crucial for working with modern computer networks.