July 20, 2019

Difference between a Private IP Address and Public IP Address

It is possible to access a public IP address over the internet. Like a postal address that is used to send a mail to a house, this kind of IP address is a globally unique one, and it is assigned to one computing device. Conversely, a private IP address is one that is allocated to systems in a private space without allowing these devices to expose to the web. For instance, if you have many computers in your house, you may need to use private IP addresses in order to address each system in the network. In this case, your router receives the public IP address, plus each of the devices connected to the equipment receives a private address from it via DHCP protocol.

IANA (Internet Assigned Numbers Authority) is the organization that is responsible for registering the address ranges to internet service providers and organizations. To allow companies to assign IP addresses without restraint, the NIC (Network Information Center) has reserved certain IP address blocks for only private use.

What is Meant by Public IP Address?

This is the kind of IP address assigned to a device to enable access directly over the internet. Candidates for a public IP address can be an e-mail server, a web server, and similar systems which can be directly accessed from the internet. It is a globally unique IP address, which can be assigned to just one unique computing device.

What is Meant by Private IP Address?

A private IP address refers to the address space that is allocated by the Network Information Center to allow companies to form their own networks. There are class A, class B, and class C IP address blocks reserved for use in private environments. The computers, smartphones and tablets in your house and the PCs in an organization are often assigned different private IP addresses. Your network printer is being assigned a private IP address so that only you and your family members can print to that device.

When a system is assigned an IP address, your local devices can see that PC via its private IP address. The devices residing beyond your local network, however, cannot communicate directly via the IP address, although they use your router’s address for this. To enable direct access to your local device that is assigned a private address, you have to use a Network Address Translator.