What is an IP Address?
It is used to generate or provide a unique address to the device connected to our network. It will help to communicate the device with each other.
There are two types of IP addresses used: IPv4 and IPv6. IP addresses are assigned to devices and networks to help manage data traffic, routing, and communication.
IPv4 Addressing
IPv4 (Internet Protocol version 4) is the most widely used IP addressing scheme. It consists of 32-bit addresses, which translates to 2^32 unique combinations. written in dotted decimal format:
For Example:
192.168.1.1
If the first IP address is 192.168.1.1, then the last IP Address in that network would be 192.168.1.254
Why does written in dotted decimal format vary from 0 to 255?
Because the computer only understands the bits and 1 byte = 8 bits and for IP Addresses we used 4 bytes so we used 32-bit addresses this is the standard we can use in IPV4.
IPv4 Address Classes
IPv4 addresses are categorized into five classes:
| Class | Starting IP | Ending IP | Default Subnet Mask |
| A | 1.0.0.0 | 126.255.255.255 | 255.0.0.0 (/8) |
| B | 128.0.0.0 | 191.255.255.255 | 255.255.0.0 (/16) |
| C | 192.0.0.0 | 223.255.255.255 | 255.255.255.0 (/24) |
| D | 224.0.0.0 | 239.255.255.255 | - |
| E | 240.0.0.0 | 255.255.255.255 | - |
IPv6 Addressing
IPv6 (Internet Protocol version 6) is the successor to IPv4, designed to handle address exhaustion. It uses 128-bit addresses and is written in hexadecimal. The reason is simple: The number of devices that want to connect to the Internet is growing tremendously, and IPv4 cannot satisfy such needs. On the other hand, thanks to the standardization of the new IPv6, it allows 3.4 x 1038 unique IP addresses, which is equal to 340 trillion trillion IP addresses.
Example of an IPv6 Address:
Because the computer only understands the bits and 1 byte = 16 bits and for IP Addresses we used 8 bytes so we used 64-bit addresses this is the standard we can use in IPV6.
SUBNET
A subnet or subnetwork is a smaller network inside a large network. Subnetting makes network routing much more efficient. It helps to
Efficient IP address utilization
Reducing network congestion
Enhancing security by isolating different network segments
CIDR Notation (Classless Inter-Domain Routing)
CIDR notation simplifies subnet masks by using a slash (/) followed by the number of network bits.
| CIDR | Subnet Mask | No. of Hosts |
| /8 | 255.0.0.0 | 16,777,214 |
| /16 | 255.255.0.0 | 65,534 |
| /24 | 255.255.255.0 | 254 |
| /30 | 255.255.255.252 | 2 |
🔹 Example:192.168.1.0/24 → 256 total IPs (254 usable)
To check the CIDR notation number of the IP Address go through the below link
cidr.xyz
Conclusion
✔ IPv4 is still widely used but has address limitations.
✔ IPv6 solves the IP shortage and is the future of networking.
✔ Subnetting & CIDR help efficiently allocate and manage IP addresses.