- APIPA- Automatic Private IP Addressing.
- It is a feature or characteristic in operating systems like windows which enables computers to self-configure an IP address and subnet mask automatically when their Dynamic Host Configuration Protocol (DHCP) server isn’t reachable.
- APIPAs IP address is (169.254.0.1 to 169.254.255.254) having 65,534 usable IP addresses, with the subnet mask of 255.255.0.0.
- Internet Engineering Task Force (IETF) has initially reserved the IPV4 address block 254.0.0/16 (169.254.0.0 – 169.254.255.255) for link-local addressing.
- From DHCP server the link-local addresses are allocated to interface in nature such that communication will be established while not getting a response.
- Then Microsoft refers to this address autoconfiguration method as Automatic Private IP Addressing (APIPA).
- The Automatic Private IP Address (APIPA) provides the configuration to check for the presence of a DHCP server in every five minutes, stated by Microsoft).
- At network configuration area if APIPA detects a DHCP server, it stops and let run the DHCP server that replaces APIPA with dynamically allocated addresses.
