Logic locking is a technique used to protect integrated circuits (ICs) from unauthorized access or intellectual property theft. XOR insertion is one of the methods employed in logic locking.
In XOR insertion, additional logic gates, typically XOR gates, are inserted into the design of the IC. These gates are strategically placed to create a "key" that is required to unlock the functionality of the IC. Without knowledge of the correct key, the IC functions incorrectly or not at all, making it difficult for unauthorized parties to reverse engineer or tamper with the design.
During the manufacturing process, the key is securely programmed into the IC, typically as a series of inputs to the XOR gates. Only those with the correct key can correctly configure the XOR gates and unlock the IC's intended functionality.
Overall, logic locking via XOR insertion helps safeguard the intellectual property of IC designs by adding an extra layer of security to prevent unauthorized access or reverse engineering.