Comprendre la différence entre IPv4 et IPv6

2.0 What is IPv4? 

You can use NAT only in the fourth version of the Internet Protocol, known as IP version 4 (IPv4). An IPv4 address is made up of four blocks of numbers ranging from 0 to 255 separated by dots.

These four numbers are four groups of eight binary digits (bits). IPv4 addresses are expressed as decimal numbers for readability.For clarity, let’s look at a common IP address: 192.168.0.1.

The table below shows how IPv4 is a binary system represented by decimal digits, for easier readability.

Decimal	Binary
192	11000000
168	10101000
0	00000000
1	00000001

3.0 What is IPv6?  

The problem with IPv4 is that it provides only approximately 4.3 billion addresses.

4.3 billion is such a small number when we factor in the increasing number of devices connecting to the internet.

To address this limitation, IPv6 was introduced. An IPv6 address is made up of eight blocks of 16-bit numbers. Each block is separated by colons and represented in hexadecimal format. IPv6 uses 128 bits for each address.

In plain speak, an IPv6 address is much longer compared to an IPv4 address. Letters and numbers make up an IPv6 address.

This is an example of an IPv6 address:2001:0db8:85a3:0000:0000:8a2e:0370:7334

4.0 Ipv4 vs IPv6 : A Comparison

IPv4 is still the most commonly used version of the Internet Protocol. That’s why there’s a huge demand for it. However, IPv6 offers more in terms of performance and security. In this section, we’ll look into IPv4 vs. IPv6.

1. Enhanced Security

IPv6 was designed with integrated security features. While these features can be added to IPv4, they don’t come pre-configured as in the case with IPv6.

2. Global Access

Around 50% of IPv4 addresses were initially reserved for the US, leading to uneven distribution worldwide. In contrast, IPv6 addresses are in higher abundance. Therefore, they can be equally distributed worldwide.

3. Potential for Streamlined Routing

Each IP version has a certain number of headers (or information fields). Some of these fields tell the computers about the type of data, the size of the packet (the data being sent), the source address (where it’s coming from), and the destination address (where it’s going).

IPv6 employs consistent and fixed headers, unlike IPv4’s variable headers. This could simplify the routing code and reduce hardware processing requirements.

4. Direct End-to-End Connectivity

There is enough IPv6 to go around, leaving NATs unnecessary.

With IPv6, each device can directly connect to the internet and communicate with websites without intermediary network address translations.

However, this creates a potential downside: devices that use IPv6 might be more vulnerable if they use the same address over the Internet all the time. The fix is to use a temporary IPv6 address that changes regularly.

5. Effortless Auto-Configuration

IPv6 offers a feature called stateless auto-configuration. Devices can autonomously assign themselves IP addresses based on their unique MAC addresses. Self-configuration makes it easy for devices to find and connect within the same network.