Here you can find all lookup results for private IP address 169.254.1.21 which is located in a class B network with reserved IP range 169.254.1.0/24.
As it is also part of the IPv4 address block 169.254.0.0/16 or (169.254.0.0–169.254.255.255), it is used for APIPA, which stands for Automatic Private IP Addressing. It is a built-in feature of operating systems like Microsoft Windows and enables computers to self-configure an IP address and subnet mask automatically when their DHCP (Dynamic Host Configuration Protocol) server isn’t reachable.
If you want to find learn more about this, check our in-depth explanation at What is APIPA?.
When designing the Internet addressing architecture, the Internet Engineering Task Force (IETF) and
the Internet Assigned Numbers Authority (IANA) have reserved various Internet Protocol (IP) addresses
and networks of various sizes (/8, /24 etc.) for special purposes or for future use.
Some are used for multicast traffic, for maintaining routing tables, for IPv4 to IPv6 translation, or to provide addressing space for public and unrestricted uses on private networks.