In the context of computer networks and the internet, Public and Private addresses refer to the two different types of IP (Internet Protocol) addresses used to identify devices connected to a network.
Public IP address:
A Public IP address is a unique address assigned to a device by an Internet Service Provider (ISP) or a network administrator. It is used to identify a device on the public internet. Public IP addresses are globally routable and accessible from anywhere on the internet. Websites, servers, and other devices that need to be reachable from the internet typically have Public IP addresses.
Private IP address:
A Private IP address is used to identify devices within a private network. These addresses are reserved for internal use and cannot be directly accessed from the internet. Instead, they are used for communication within a local network (e.g., home network or corporate intranet). Private IP addresses are not unique globally, but they must be unique within the local network they belong to.
Private IP address ranges, as defined by the Internet Assigned Numbers Authority (IANA), are:
- 10.0.0.0- 10.255.255.255 (Class A network)
- 172.16.0.0- 172.31.255.255 (Class B network)
- 192.168.0.0- 192.168.255.255 (Class C network)
Network Address Translation (NAT) is a method used to allow devices with Private IP addresses to access the internet using a single Public IP address assigned by the ISP. NAT translates the Private IP addresses to the Public IP address when data travels between the local network and the internet.
In summary, Public IP addresses are used to identify devices on the internet, while Private IP addresses are used for communication within a local network and are not directly reachable from the internet.
