As specified in RFC5735, this is an address from the "link local" block. It is assigned to a network interface as a temporary address, for instance if no static address is configured and the DHCP server is not found.
If you boot your PC without a network cable, you'll probably end up with a 169.254.*.* address.
When a computer restarts without a hardware power-down-power-up cycle, it is doing an update.
Answer:
Measures including device data encryption, anti-malware software, and communications encryption.
