Difference Between IPv4 and IPv6

Last Updated : 27 Dec, 2024

In the digital world, where billions of devices connect and communicate, Internet Protocol (IP) Addresses play a crucial role. These addresses are what allow devices to identify and locate each other on a network.

To know all about IP Addresses - refer to What is an IP Address?

Currently, there are two primary versions of Internet Protocol in use: IPv4 and IPv6. Each version has distinct characteristics, capabilities, and was developed to meet the specific needs of the internet's growth. IPv4 was the first to be widely implemented, laying the groundwork for early network communications.

However, as the internet grew and more devices started connecting online, the limitations of IPv4 became clear, leading to the creation of IPv6. This newer version was designed to address the shortcomings of its predecessor and to future-proof the network against an ever-increasing demand for more addresses and improved network efficiency.

Let’s explore their differences, why both are still in use, and the advantages each offers.

Table of Content

What is IPv4?

IPv4, or Internet Protocol version 4, is the original addressing system of the Internet, introduced in 1983. It uses a 32-bit address scheme, which theoretically allows for over 4 billion unique addresses (2^32). IPv4 addresses are typically displayed in decimal format, divided into four octets separated by dots. For example, 192.168.1.1 is a common IPv4 address you might find in a home network.

IPv4 Address Format

IPv4 Address Format is a 32-bit Address that comprises binary digits separated by a dot (.).

Characteristics of IPv4

32-bit address length: Allows for approximately 4.3 billion unique addresses.
Dot-decimal notation: IP addresses are written in a format of four decimal numbers separated by dots, such as 192.168.1.1.
Packet structure: Includes a header and payload; the header contains information essential for routing and delivery.
Checksum fields: Uses checksums in the header for error-checking the header integrity.
Fragmentation: Allows packets to be fragmented at routers along the route if the packet size exceeds the maximum transmission unit (MTU).
Address Resolution Protocol (ARP): Used for mapping IP network addresses to the hardware addresses used by a data link protocol.
Manual and DHCP configuration: Supports both manual configuration of IP addresses and dynamic configuration through DHCP (Dynamic Host Configuration Protocol).
Limited address space: The main limitation which has led to the development of IPv6 to cater to more devices.
Network Address Translation (NAT): Used to allow multiple devices on a private network to share a single public IP address.
Security: Lacks inherent security features, requiring additional protocols such as IPSec for secure communications.

Drawbacks of IPv4

Limited Address Space : IPv4 has a limited number of addresses, which is not enough for the growing number of devices connecting to the internet.
Complex Configuration : IPv4 often requires manual configuration or DHCP to assign addresses, which can be time-consuming and prone to errors.
Less Efficient Routing : The IPv4 header is more complex, which can slow down data processing and routing.
Security Issues : IPv4 does not have built-in security features, making it more vulnerable to attacks unless extra security measures are added.
Limited Support for Quality of Service (QoS) : IPv4 has limited capabilities for prioritizing certain types of data, which can affect the performance of real-time applications like video streaming and VoIP.
Fragmentation : IPv4 allows routers to fragment packets, which can lead to inefficiencies and increased chances of data being lost or corrupted.
Broadcasting Overhead : IPv4 uses broadcasting to communicate with multiple devices on a network, which can create unnecessary network traffic and reduce performance.

What is IPv6?

Another most common version of the Internet Protocol currently is IPv6. The well-known IPv6 protocol is being used and deployed more often, especially in mobile phone markets. IPv6 was designed by the Internet Engineering Task Force (IETF) in December 1998 with the purpose of superseding IPv4 due to the global exponentially growing internet of users.

IPv6 stands for Internet Protocol version 6. IPv6 is the new version of Internet Protocol, which is way better than IPv4 in terms of complexity and efficiency. IPv6 is written as a group of 8 hexadecimal numbers separated by colon (:). It can be written as 128 bits of 0s and 1s.

IPv6 Address Format

IPv6 Address Format is a 128-bit IP Address, which is written in a group of 8 hexadecimal numbers separated by colon (:).

To switch from IPv4 to IPv6, there are several strategies:

Dual Stacking : Devices can use both IPv4 and IPv6 at the same time. This way, they can talk to networks and devices using either version.
Tunneling : This method allows IPv6 users to send data through an IPv4 network to reach other IPv6 users. Think of it as creating a "tunnel" for IPv6 traffic through the older IPv4 system.
Network Address Translation (NAT) : NAT helps devices using different versions of IP addresses (IPv4 and IPv6) to communicate with each other by translating the addresses so they understand each other.

Characteristics of IPv6

IPv6 uses 128-bit addresses, offering a much larger address space than IPv4's 32-bit system.
IPv6 addresses use a combination of numbers and letters separated by colons, allowing for more unique addresses.
The IPv6 header has fewer fields, making it more efficient for routers to process.
IPv6 supports Unicast, Multicast, and Anycast, but no Broadcast, reducing network traffic.
IPv6 allows flexible subnetting (VLSM) to divide networks based on specific needs.
IPv6 uses Neighbor Discovery for MAC address resolution instead of ARP.
IPv6 uses advanced routing protocols like OSPFv3 and RIPng for better address handling.
IPv6 devices can self-assign IP addresses using SLAAC, or use DHCPv6 for more control.
IPv6 handles fragmentation at the sender side, not by routers, improving speed.