What is an IP address and what is it used for?

What is an IP address and what is it used for?

The significance of the internet and network communication in today’s society is immense and invaluable. The internet has become an essential component of daily life for billions of people worldwide.

One of the most important aspects of communication on the internet is the IP address, as it enables the identification and routing of data between different devices and locations across the globe.

What is an IP address?

An IP address, short for “Internet Protocol address,” is a key element in the world of network communication and internet connectivity. This numerical identifier allows devices to be recognized and communicate within the global network known as the internet. The following sections will discuss the basic characteristics of an IP address, including its format, versions, and assignment to devices.

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IP Address Format:

An IP address is typically represented as a string of numbers separated by periods. An example of such an address in the IPv4 version (Internet Protocol Version 4) might look like this: “”. This format contains four numbers ranging from 0 to 255, with each representing an octet. Each of these digits is an 8-bit binary number, collectively forming 32 bits. The addresses are usually separated by periods for easier reading and identification.

IP Address Versions:

There are two main versions of IP addresses – IPv4 and IPv6. IPv4 addresses are the most commonly used and are recognizable by their four-octet format. However, due to the limited number of available IPv4 addresses, a new version, IPv6, was developed. IPv6 uses 128 bits and allows for a significantly larger number of possible addresses. This change was necessary to accommodate the growing number of devices connected to the internet, such as smart devices, IoT (Internet of Things) devices, and other technological innovations.

Assigning IP Addresses to Devices

IP addresses are assigned to devices in different ways, depending on the network architecture. There are two primary methods of assigning IP addresses: dynamic and static assignment.

  • Dynamic assignment is the most common method and involves the automatic assignment of an IP address to a device by a DHCP (Dynamic Host Configuration Protocol) server. This server automatically assigns an IP address to the device each time it connects to the network. This method is practical and efficient for dynamic networks, such as home or business networks.
  • Static assignment is used when specific devices are given fixed IP addresses. This is typically applied to devices with specific functions, such as servers or devices that require constant availability under the same IP address.

IP Address Function

The main function of IP addresses in the world of network communication is to enable the routing of data and the identification of devices within a network. These addresses are essential for the functioning of the internet and network infrastructure.

Data Routing:

IP addresses play a crucial role in the process of routing data over the internet. When data is sent from one device to another, the IP address is used to direct it from the source to the destination. Every device on the internet has its unique IP address used for identification. To ensure that data reaches its exact destination, network devices use routing tables and routes, using the IP address as a reference. In this way, IP addresses enable the efficient travel of data through the network and ensure it arrives at the correct location.

Device Identification:

IP addresses are also used to identify devices within a network. For example, when you access a website, the web server uses your IP address to know where the request for content is coming from. This allows the server to properly respond to your request and deliver the desired content. Additionally, when sending an email, the IP address is used to identify the sender and recipient to ensure the correct delivery of the electronic message.

There are numerous examples of IP address usage. When you type a web address into your internet browser, DNS (Domain Name System) servers translate that address into the corresponding IP address to direct the request to the appropriate web server. Similarly, when exchanging data over P2P (peer-to-peer) networks or using various applications on smartphones, IP addresses are used to identify devices and establish communication between them.

IP addresses are crucial for the efficient routing of data over the internet and for enabling the identification of devices within a network. Without them, the internet and network communication as we know it today would not be possible. IP addresses form the foundation for successful data exchange and the functionality of the global network.

IPv4 vs. IPv6

IPv4 (Internet Protocol Version 4) and IPv6 (Internet Protocol Version 6) are the two main versions of IP addresses used for identifying and routing data in networks. There are significant differences between these two versions in terms of format and the number of bits.


  • IPv4 addresses consist of four decimal numbers (octets) separated by periods, for example,
  • Each octet has 8 bits, which makes a total of 32 bits.
  • IPv4 has a limited number of addresses, specifically, approximately 4.3 billion possible addresses.
  • The limited number of addresses has led to an IP address shortage problem, especially with the increasing number of devices connected to the internet.


  • IPv6 addresses are significantly longer and more complex, represented by hexadecimal numbers separated by colons, for example, 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
  • Each IPv6 address has a total of 128 bits, which is significantly more than IPv4.
  • This large number of bits allows for an enormous number of potential addresses, approximately 340 undecillion addresses (3.4 × 10^38), which is practically inexhaustible and meets all future needs for connecting devices.

Need to transition to IPv6:

The primary reason for transitioning from IPv4 to IPv6 is the exhaustion of IPv4 addresses. With the expansion of the internet and the increasing number of connected devices, it has become evident that IPv4 addresses will be insufficient for internet needs. The limited number of IPv4 addresses has led to issues in allocating new addresses and escalating prices of existing addresses in the market.

IPv6 addresses this resource shortage by providing a significantly larger number of addresses. This enables the internet to grow without limitations and ensures that there will be enough addresses for all devices and applications in the future.

IPv4 and IPv6 represent two different versions of IP addresses with significant differences in format and bit numbers. Transitioning from IPv4 to IPv6 is necessary to meet the growing demand for addresses and to facilitate uninterrupted growth of the internet and network communication.

Public and private IP addresses

Public and private IP addresses are two different categories of IP addresses used in the world of network communication, each serving specific purposes and roles. Here’s how they differ and how private IP addresses are used to identify devices within local networks.

Public IP addresses:

  • Public IP addresses are addresses visible on the internet and used to identify devices in the global network.
  • Every device that wants to be directly accessible on the internet must have a unique public IP address.
  • Public IP addresses are a limited resource allocated by the Internet Assigned Numbers Authority (IANA) and its subsidiaries, such as internet service providers (ISPs).
  • These ISPs receive a certain number of public IP addresses which they then allocate to their customers.

Private IP addresses:

  • Private IP addresses are addresses used within private networks, such as home or business networks, and are not visible from the internet.
  • They enable identification and communication of devices within a local network, but they are hidden from the outside world.
  • The most well-known ranges of private IP addresses are to, to, and to
  • Private IP addresses are free and do not need to be registered with IANA or ISPs.

Using private IP addresses for local networks:

Private IP addresses are used to identify devices within local networks, such as home Wi-Fi networks or corporate Local Area Networks (LANs). To enable communication between devices within the same network, local routing is used, facilitating data exchange among devices with private IP addresses within the network.

Routing is done at the local network level and does not require visibility from the internet. This approach ensures privacy and security of devices within the local network, as private IP addresses are isolated from external threats. It also enables sharing of resources within the network, such as files and printers, without the need for public IP addresses.

The difference between public and private IP addresses lies in their visibility on the internet and their purpose. Private IP addresses are used to identify devices within local networks and provide a secure and efficient means of communication within those networks, whereas public IP addresses are used to identify devices on the global network, the internet.

The significance of IP addresses in everyday life

IP addresses play a crucial role in our everyday lives by enabling connectivity, communication, and access to the internet, which has become indispensable in today’s digital age.

  1. Browsing the internet: When we use web browsers, IP addresses are used to identify web servers and enable the transfer of web pages, images, video content, and other resources to our devices.
  2. Using smart devices: Smartphones, smart TVs, smart homes, and other IoT devices communicate via IP addresses. For example, an IP address enables remote control of smart devices through applications.
  3. Applications and social networks: Everyday applications such as social networks, email, voice and video calls also rely on IP addresses to facilitate communication between users worldwide.
  4. Business and e-commerce: The internet has become a crucial platform for business. IP addresses are essential for e-commerce, online payments, exchanging business messages, and accessing business applications.
  5. Global connectivity: IP addresses enable global connectivity, facilitating communication and collaboration with people and organizations worldwide. Without IP addresses, global connectivity and global business would be significantly hindered.

In today’s digital age, IP addresses are a fundamental infrastructure component enabling communication, access to information and services, and management of smart devices. Their significance in business, communication, and global connectivity cannot be overstated, as they are crucial for our daily interaction with the digital world.