Computer Networks mainly use the IP (Internet Protocol) Address in order to communicate with each other. There are different types of IP addresses which APIPA (Automatic Private IP Addressing) is one of them. The APIPA is used to configure IP addresses without any external service like DHCP server etc. The APIPA address is assigned and used when the computer can not access the DHCP server and set a random APIPA address. The APIPA address range 169.254.0.1-169.254.255.254 and subnet mask is 255.255.0.0 .
The computer uses the ARP protocol in order to check if the selected APIPA address is not used by another computer to prevent collusion. Event an APIPA address is assigned to a computer the computer regularly checks a DHCP server in order to get a dynamic IP address from the DHCP server.