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Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks.

Understanding IPv4: The Backbone of Internet Connectivity

In the vast expanse of digital communication, a foundational protocol stands out for its pivotal role in connecting devices across the globe - IPv4 or Internet Protocol version 4.

What is IPv4?

IPv4 is the fourth iteration of the Internet Protocol (IP), and until the advent of IPv6, it was the dominant protocol used for almost all Internet traffic. Designed in the early 1980s, IPv4 facilitates the unique identification of devices on a network through an addressing system, making it possible to transfer data between them seamlessly. An IPv4 address is a 32-bit number, typically displayed as four decimal numbers separated by periods, each ranging from 0 to 255 - for instance,

How Does IPv4 Work?

At its core, IPv4's job is to enable the successful transmission of data packets from a source device to a destination device, following these basic steps:

  1. Addressing: Each device connected to the Internet or a local network is assigned a unique IPv4 address, which identifies it within the network.
  2. Data Packet Creation: Data intended for transmission is divided into smaller units called packets. Each packet is tagged with the sender and receiver's IPv4 addresses.
  3. Routing: Network equipment like routers use the destination IPv4 address to direct each packet through the Internet or local networks to its destination.
  4. Reassembly: Upon reaching their destination, the packets are reassembled correctly to reconstruct the original data.

Common Uses of IPv4

Though we seldom think about IPv4 as we browse the web or stream a video, this protocol is hard at work behind the scenes. Here are some common uses of IPv4 in everyday internet activities:

  • Web Browsing: Each time you visit a website, your device uses IPv4 to communicate with the web server hosting that site. The domain name you enter is resolved to an IPv4 address using DNS (Domain Name System), directing your request to the correct server.
  • Email: Sending and receiving emails would not be possible without IPv4. Email servers use these addresses to exchange messages, ensuring they reach the intended recipient's device.
  • Online Gaming: Multiplayer online games rely on IPv4 to exchange data between players' devices and game servers, facilitating real-time interaction and gameplay.
  • Streaming Services: Platforms like Netflix, YouTube, and Spotify use IPv4 to deliver content from their servers to your device. The protocol ensures that data packets comprising video or audio streams reach you promptly and in order.
  • Remote Work and VPNs: Virtual Private Networks (VPNs) use IPv4 to create secure connections to remote networks, enabling access to resources as if the user were physically connected to the network.
  • Smart Home Devices: In the realm of the Internet of Things (IoT), smart devices such as thermostats, security cameras, and lighting systems use IPv4 to communicate with apps and other devices over the Internet.

Navigating the IPv4 Limitation

Despite its foundational role in the Internet's growth, IPv4 has a significant limitation: its 32-bit addressing scheme can support only about 4.3 billion unique addresses. With the explosion of internet-connected devices, this pool of addresses is nearly depleted, leading to the development and gradual adoption of IPv6, which offers a vastly larger address space thanks to its 128-bit addressing.


IPv4 has been an essential building block in the development and expansion of the Internet. Its simple yet effective protocol has facilitated countless innovations and remains at the heart of most online activities. Even as we transition towards IPv6 to accommodate the growing number of devices, IPv4's contributions to global connectivity are undeniable. Understanding IPv4 gives us insight into how the Internet works and appreciates the intricate systems that keep us connected in an increasingly digital world.

Synonyms: Internet Protocol version 4