What is Automatic Private IP Addressing (APIPA) and what does it indicate when a Windows device shows a 169.254.x.x address?

• A.APIPA addresses are assigned by the ISP when private addresses run out; 169.254.x.x is the ISP's backup addressing range
• B.APIPA is a valid IP addressing scheme for large enterprise networks; 169.254.0.0/16 provides 65,534 addresses for corporate use
• C.APIPA (RFC 3927): when a Windows device fails to obtain an IP via DHCP (all DHCP Discover messages go unanswered), it self-assigns an address from 169.254.0.0/16 (link-local) using ARP to check for conflicts. A 169.254.x.x address indicates a DHCP failure: the DHCP server is unreachable, the DHCP scope is exhausted, or the network link is disconnected
• D.APIPA only occurs on Linux systems; Windows always falls back to 0.0.0.0 if DHCP fails