What is is a private IP Address, which is used by many of the router manufacturers as the default IP Address. This is fabricated within the firmware of the router and allows a user to access the device through a web browser running on a computer which is connected with the device.

Being a default IP Address does not mean that it cannot be changed by the user. If the user want, he can change the IP Address to anything other than depending upon his needs and requirements.

What are Private IP Addresses

In the Internet addressing architecture, a private network is a network that uses private IP address space. These addresses are commonly used for home, office, and enterprise local area networks (LANs), when globally routable addresses are not mandatory, or are not available for the intended network applications. Private IP address spaces were originally defined in an effort to delay IPv4 address exhaustion, but they are also a feature of the next generation Internet Protocol, IPv6.

These addresses are characterized as private because they are not globally delegated, meaning they are not allocated to any specific organization, and IP packets addressed by them cannot be transmitted onto the public Internet. Anyone may use these addresses without approval from a regional Internet registry (RIR). If such a private network needs to connect to the Internet, it must use either a network address translator (NAT) gateway, or a proxy server.

The Internet Engineering Task Force (IETF) has directed the Internet Assigned Numbers Authority (IANA) to reserve the following IPv4 address ranges for private networks.

RFC1918 name IP address range number of addresses
24-bit block – 16,777,216
20-bit block – 1,048,576
16-bit block – 65,536

If you want to have a list of routers and modems working on default IP Address, please visit out post on Router: Password, Admin List and Details.