1.8 Concept of IP Addressing

 

1.8 Concept of IP Addressing

An Internet Protocol (IP) Address is a unique numerical address assigned to every device connected to a network and routing data between devices. It identifies the device and allows data to be sent to and received from the correct destination.

Internet Protocol (IP) is a set of rules that identifies devices on a network and controls how data is sent from one device to another.

IP works like a postal system. It gives every device a unique address and ensures that data reaches the correct destination.

 

An IP address is important because it:

• Identifies each device on a network.
• Allows devices to communicate with one another.
• Helps route data to the correct destination.
• Prevents data from being delivered to the wrong device.

 

IPv4 (Internet Protocol version 4) and IPv6 (Internet Protocol version 6) are two different versions of the Internet Protocol.

 

IPv4 (Internet Protocol Version 4)

 

IPv4 (Internet Protocol Version 4) is the fourth version of the Internet Protocol that uses a 32-bit address to uniquely identify devices and enable communication over a network.

 

Features of IPv4

• Uses a 32-bit IP address.
• Can generate about 4.29 billion unique IP addresses.
• Addresses are written in decimal numbers separated by dots (.). (e.g., 192.168.1.1)
• An IPv4 address consists of 4 octets, with each octet containing 8 bits.
• It is simple, fast, and widely supported by network devices.

 

How IPv4 Works

1. Every device connected to a network is assigned a unique IPv4 address.
2. When data is sent, the sender includes the destination IPv4 address in the data packet.
3. Routers read the destination address and forward the packet through the network.
4. The data reaches the correct destination device.

 

Limitation of IPv4

The biggest limitation of IPv4 is its limited number of addresses.

As the number of computers, smartphones, tablets, and other Internet-connected devices has increased rapidly, the available IPv4 addresses have nearly run out. This problem is known as IPv4 address exhaustion.

Solutions to IPv4 Address Exhaustion

To reduce the shortage of IPv4 addresses, the following techniques are used:

1. Network Address Translation (NAT)

• NAT allows multiple devices in a private network to share a single public IPv4 address.
• It helps conserve public IPv4 addresses.

Example: In a home Wi-Fi network, several devices (phones, laptops, TVs) use one public IP address provided by the Internet Service Provider (ISP).

2. Private IP Addresses

• Private IP addresses are used inside local networks, such as homes, schools, and offices.
• These addresses are not accessible directly from the Internet.
• They reduce the need for public IPv4 addresses.

IPv6 (Internet Protocol Version 6)

IPv6 (Internet Protocol Version 6) is the latest version of the Internet Protocol that uses a 128-bit address to identify devices and provide communication over a network.

Features of IPv6

• Uses a 128-bit IP address.
• Can generate approximately 3.4 × 10³⁸ unique IP addresses.
• Addresses are written in hexadecimal notation and separated by colons (:).
• An IPv6 address consists of 8 groups, with each group containing 4 hexadecimal digits.
• Provides better security, faster communication, and automatic address configuration.

Address Format

IPv6 addresses are written in hexadecimal notation.

Example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334

The address consists of 8 groups, and each group contains 4 hexadecimal digits (0–9 and A–F).

How IPv6 Works

1. A device connected to a network receives an IPv6 address automatically or from a network administrator.
2. When data is sent, the destination IPv6 address is attached to the data packet.
3. Routers read the destination IPv6 address.
4. The data is forwarded through the network.
5. The data reaches the correct destination device.

Why Was IPv6 Developed?

IPv6 was developed to overcome the limited address space of IPv4 and to provide better security, improved performance, and support for the growing number of Internet-connected devices.

Key Features Explained

1. Automatic Address Configuration (Auto-Configuration)

IPv6 can automatically assign an IP address to a device without requiring manual configuration or a DHCP server.

Example: When you connect a new computer to an IPv6 network, it can automatically obtain its own IP address.

2. Built-in Security

IPv6 includes built-in support for IPsec, which helps protect data by providing authentication and encryption during communication.

3. Multicast Communication

IPv6 supports multicast, which allows one device to send data to multiple selected devices at the same time, reducing unnecessary network traffic.

Difference Between IPv4 and IPv6

Basis	IPv4	IPv6
Address Length	IPv4 uses a 32-bit IP address.	IPv6 uses a 128-bit IP address.
Address Format	IPv4 addresses are written in decimal notation and separated by dots (.), e.g., 192.168.1.1.	IPv6 addresses are written in hexadecimal notation and separated by colons (:), e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
Address Space	IPv4 can generate about 4.29 billion (4.29 × 10⁹) unique IP addresses.	IPv6 can generate approximately 3.4 × 10³⁸ unique IP addresses.
Configuration	IPv4 mainly uses manual configuration or DHCP to assign IP addresses.	IPv6 supports automatic address configuration (Auto-Configuration) as well as manual configuration.
Security	IPv4 does not provide built-in encryption and authentication.	IPv6 includes built-in security (IPsec) with encryption and authentication support.
Purpose	IPv4 was developed for the early Internet but has a limited number of IP addresses.	IPv6 was developed to overcome IPv4 address exhaustion and support the growing number of Internet-connected devices.