(
Automatic
Private
IP Addressing) The Windows function that provides DHCP autoconfiguration addressing. APIPA assigns a class B IP address from 169.254.0.0 to 169.254.255.255 to the client when a DHCP server is either permanently or temporarily unavailable. Designed for small non-routable networks, if a DHCP server becomes available later, the APIPA address is replaced with one from the DHCP server. For example, when a Windows Vista machine starts up, it waits only six seconds to find a DHCP server before assigning an IP from the APIPA range. It then continues to look for a DHCP server. Previous versions of Windows looked for a DHCP server for up to three minutes. See
DHCP autoconfiguration addressing,
DHCP and
private IP address.
An IP Assigned by APIPA
This IP address was assigned by APIPA, and the IPCONFIG utility reports the IP as an "Autoconfiguration IP address." See
IPCONFIG.