Types of IP Addresses Explained: IPv4, IPv6, Public vs. Private

Introduction

Have you ever wondered how your devices connect to the internet? In today’s digital world, at the core of it all are IP (Internet Protocol) addresses, they serve as a unique identifier that allows devices to find and communicate with each other. There are multiple types of IP addresses, each designed for specific purposes and settings. This article will guide you through the different types of IP addresses, helping you understand their uses and distinctions.

Types of IP Address

IPv4 vs. IPv6

IPv4 (Internet Protocol version 4) is the original format for IP addresses, which has been around since the early days of the internet,  and uses a 32-bit system that allows for approximately 4.3 billion unique addresses. An example of an IPv4 address is: 192.168.1.1. IPv4, but with the growing number of devices, IPv4 quickly ran out of unique combinations and reached its capacity limits. And due to that limitation, IPv6 enters the conversation.

IPv6 (Internet Protocol version 6) was developed to overcome the issues mentioned, that is why it uses a 128-bit address system. IPv6 provides an almost limitless number of addresses, around 340 undecillion, enough to cover future demands. An example IPv6 address is 2001:0db8:85a3:0000:0000:8a2e:0370:7334. IPv6 also brings improvements like simplified header formats and enhanced security features.

To summarize, the differences between IPv4 and IPv6 are:

• Address Format: IPv4 uses a numeric, dotted-decimal format, while IPv6 uses hexadecimal notation separated by colons.
• Size and Capacity: IPv4 has a 4.3 billion address limit. IPv6’s vast capacity addresses this shortage by offering more addresses.
• Use Cases and Efficiency: IPv4 remains the default in many networks, but IPv6 adoption is growing, especially in systems requiring scalable and efficient address management. IPv6 supports autoconfiguration, making it easier to manage, particularly for complex networks.

So why is it necessary to know the difference between the two of them? Because it gives a better understanding of the expanded range that makes IPv6 better suited to support the growing “Internet of Things” (IoT) devices and helps alleviate IPv4’s limitations.

Public vs. Private IP Addresses

Public IP Address is an address that can be accessed over the internet and is assigned by Internet Service Providers (ISPs). It uniquely identifies devices on the wider internet, allowing them to communicate with external networks and other devices globally. Public IP addresses are visible on the internet and play a crucial role in routing data between different networks. An example is Google’s public IP, 8.8.8.8, which anyone can access to. 

Private IP Address is used within local networks (LANs), such as homes or offices, and is not routable on the internet. These addresses are typically assigned to devices like computers, printers, and routers within a private network. A common private IP ranges include 192.168.x.x (commonly used in home networks) and 10.x.x.x. Private IPs rely on a process called Network Address Translation (NAT) to communicate with public IPs, allowing multiple devices in a local network to share a single public IP address for external communication.

‍

Static vs. Dynamic IP Addresses

Static IP Addresses are fixed addresses that are permanently assigned to a device by an administrator. These addresses remain constant over time, allowing for consistent and reliable communication. Static IP addresses are commonly used for servers hosting websites and email servers.

Dynamic IP Addresses are assigned automatically through a protocol called DHCP (Dynamic Host Configuration Protocol). With the dynamic addressing, devices on a network are allocated IP addresses from a pool of available addresses for a specific period, which can change upon reconnecting or restarting. These types of IP addresses are ideal for personal devices in home networks.

Let’s check the differences!

Static IP Addresses: 

• Best for servers, network equipment, and services that require a permanent address for accessibility
• Reliable and easier to manage for servers and services; essential for remote access and hosting. 
• It is more expensive and requires manual configuration; susceptible to hacking due to fixed location.

Dynamic IP Addresses: 

• Ideal for personal devices in home networks, useful in environments with multiple devices that connect and disconnect frequently.
• Cost-effective and easier to manage; reduces the risk of hacking; ideal for large networks with many users. 
• Less reliable for hosting; potential connectivity issues when an address changes; can complicate remote access configurations.

Shared vs. Dedicated IP Addresses

Shared IP Address is an IP that is used by multiple websites hosted on the same server. This setup allows various users to share server resources, significantly reducing hosting costs. But it can also lead to potential issues, such as slower load times and complications related to email deliverability.

Dedicated IP Address is an IP assigned exclusively to a single user or domain. It means that only one website will use that IP address, providing a unique online identity. Dedicated IPs are often preferred for businesses or services that require a stable and reliable connection. For example, they are essential for SSL certificates and they have better control over IP reputation, businesses can mitigate any risks, ensuring their online activities are not impacted negatively by others.

Local vs. Global IP Addresses

Local IP Address is an address used within a private network, allowing devices to interact with one another without needing direct internet access. These addresses are not routable outside the local network and are typically assigned from designated private IP address ranges, for example: 192.168.x.x, 10.x.x.x, or 172.16.x.x to 172.31.x.x. In a home or office setting, local IP addresses allow devices like computers, smartphones, and printers to interact seamlessly, facilitating tasks such as file sharing and printing without requiring public internet connectivity.

Global IP Address is unique across the entire internet and is necessary for communication with external networks. Each one of the global IP addresses identifies a specific device or network location, ensuring that data sent over the internet reaches its intended destination, and also they are are assigned by ISPs

What do you know about the interaction via routers and NAT?

Local and global IP addresses interact through routers, which act as gateways between local networks and the internet. Their addresses work together to facilitate seamless connectivity and communication.

How does it work? 

When a device with a local IP address needs to access the internet, the router uses Network Address Translation (NAT) to translate the local IP into the global IP address assigned to the router. 

What is the goal?

This process allows multiple devices within a private network to share a single public IP address while maintaining their unique local addresses.

IP Address Assignment

How does it work?

IP addresses assignment depends on the type of network and address, let’s check the different cases:

• Public IP addresses are typically assigned by Internet Service Providers (ISPs),  ISPs obtain blocks of IP addresses from regulatory organizations to distribute to their customers as needed.
• Dynamic IP addresses are automatically assigned to devices using the Dynamic Host Configuration Protocol (DHCP), DHCP simplifies network management allowing different types of devices to connect seamlessly without manual setup.

Which organizations are involved in managing and distributing IP addresses globally?

At the top is the Internet Assigned Numbers Authority (IANA), which oversees the global allocation of IP addresses. IANA delegates large blocks of IPs to Regional Internet Registries (RIRs), which are responsible for allocation within specific regions. Examples of RIRs include ARIN (American Registry for Internet Numbers) for North America and RIPE NCC (Réseaux IP Européens Network Coordination Centre) for Europe and surrounding areas.

So why are these RIRs so important? 

Because they work with ISPs and other entities to ensure the fair and efficient distribution of IP addresses across the globe, enabling organized and structured connectivity on the internet.

Common Misconceptions About IP Addresses

The primary misconception is regarding privacy and tracking. Is a common myth that an IP address can reveal someone’s exact physical location. IP addresses provide general location data (city or region), and they are not precise enough to pinpoint a specific address or individual. 

On a related note, another misconception is that an IP address directly identifies a person. But in reality, an IP address only identifies a device or network. Even though an IP address can hint at activity on a network, it cannot confirm the identity of a specific user.

Lastly, people may believe that IP addresses can be used for tracking to some extent, however IP addresses offer basic location and network data, so they have significant privacy limitations that restrict their ability to serve as precise tracking tools.

‍