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What is an IP address and why is it important?

An IP is an internet protocol address and every type of network device — ie anything connected to the internet — is assigned one
People using a variety of internet-connected devices.

An IP is an internet protocol address. Essentially, it is a numeric value assigned to a network device, and it is used for the identification and location of a network device.

IP addresses are assigned to every type of network device. It could be an IP camera, a laptop, a desktop device, an IP phone, a cell phone on a wireless network, computer servers, or websites. Even children’s toys that are internet connected will have an IP address assigned to them.

IPs are broken up into IPv4 and IPv6. IPv4 is made up of a 32-bit address. IPv6 is the new standard and is made up of 128-bit addresses. IPv6 came out because all possible IPv4 addresses are close to being assigned, so IPv6 is the new standard.

IP conflict

A subnet cannot have a duplicate IP address. This means that if your laptop has an IP address of, no other devices on your network can have that IP address as it causes an IP conflict. If two devices have the same IP address, the network will confuse the devices, and to resolve the conflict, one will be kicked off the network.

Generally, the network will initially accept the second device, and when it realises there is a conflict, it will kick the first device off the network.

Managing IP addresses

Managing IP addresses is therefore important. You can assign IP addresses statically, which means you manually allocate an IP address to a device. You normally see this with servers because you want the server address to stay constant.

IP addresses can also be assigned dynamically, where a DHCP server will assign IP addresses to devices as they join the network. The DHCP server will have a pool of IP addresses and will manage their assignment to avoid IP conflicts.

The DHCP also manages the lease of these IP addresses, which can be any amount of time. When the lease is over, the device releases the IP address back to the DHCP server and the device is assigned a new IP address.


IP addresses are therefore used to identify devices and are unique to a device within a subnet. An IP address can be masked through VPN. However, if it is not masked, you can use it to trace a device’s location or the origin of an email.

IP addresses are also very useful in troubleshooting network errors and identifying intruders.

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