Most methods of securing SOCs involve storing a root key that provides the basis of all derived keys and encryption of communication. The weakness with these methods is that even if the root key is stored in secure non-volatile memory, there are often methods to read the key. Once a key has been divulged the device can be cloned and its security is compromised. With long and complex supply chains there is a likelihood that physical devices may come within reach of attackers. With physical access, made easy through supply chains or remote deployment, such as is often the case with IoT devices, keys stored in eFuses, Flash EEPROM or even OTP NVM can be detected.

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