Detecting and preventing frequency attacks

A root of trust (ROT) circuit comprising:

• one or more circuits to:
• implement a ROT and at least one frequency monitoring circuit;
• use the at least one frequency monitoring circuit to monitor a clock signal generated by a processor coupled to the ROT circuit;
• and
• determine whether to assert a control signal based on a comparison between a frequency of the clock signal and a predetermined threshold.

A method comprising:

• monitoring a clock signal provided from a first device to a second device;
• performing a comparison of a frequency of the clock signal with a predetermined threshold frequency;
• and
• determining whether to assert a control signal based on the comparison.