IP Address Glossary
IP (Internet Protocol):
What it is: A set of rules that allows devices to send data to each other across a network or the internet.
Why it matters: Every device needs an IP address so it can be identified and reached, much like a postal address for digital communication.
How it works: Data is broken into packets, labelled with source and destination IP addresses, and routed across networks until it reaches the right device.
***
IPv4 (Internet Protocol version 4):
What it is: The fourth version of the Internet Protocol and the most widely used addressing system on the internet.
Address format: Four numbers separated by dots, for example: 192.168.1.10.
Capacity: About 4.3 billion unique addresses.
Why it matters: IPv4 has been the backbone of the internet for decades, but the number of available addresses is limited, which led to the development of IPv6.
***
IPv6 (Internet Protocol version 6):
What it is: The newer version of the Internet Protocol designed to replace IPv4.
Address format: Eight groups of hexadecimal numbers separated by colons, for example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
Capacity: Effectively unlimited—enough to give every device on Earth (and many more) a unique address.
Why it matters: Supports the growth of the internet, improves routing efficiency, and includes built-in security features like mandatory support for IPsec.
***
CIDR (Classless Inter‑Domain Routing):
What it is: A method for defining IP address ranges more efficiently than the old “class‑based” system.
How it works: An IP address is followed by a slash and a number that indicates how many bits of the address define the network. Example: 192.168.1.0/24.
Why it matters: CIDR helps reduce wasted IP space, improves routing, and is essential for modern network design and firewall rules.
***
Subnet (Subnetworks):
What it is: A smaller, logical section of a larger network.
Why it matters: Subnets help organise networks, improve performance, and control access by grouping devices.
Example: A company might split its network into subnets for staff, guests, and servers.
***
IP Address Range:
What it is: A block of IP addresses defined using CIDR notation.
Why it matters: Commonly used for firewall rules, access control lists, and routing decisions.
Example: 10.0.0.0/16 represents 65,536 IPv4 addresses.
***
Public vs Private IP Addresses:
Public IP: Routable on the internet and globally unique.
Private IP: Used inside local networks and not reachable from the internet.
Why it matters: Private IPs conserve public address space and improve security.
If you have any further questions, please contact our Customer Service team.