A. IP Address
B. MAC Address
I have been asked this question in an interview for internship.
This is a very interesting question from Setting up Devices in Intel IoT Analytics topic in division Analyzing Huge Amount of Data with Cloud – based IoT Analytics of IOT
To explain I would say: The Iotkit-admin device-id command line will generate an output line such as the following one with the device ID. By default, the device ID is equal to the MAC address of the network interface card
2016-04.05T02:23:170Z – info: Device ID: 98-4F-EE-01-75-72.