Misalignment of the PCB layers during manufacturing only causes local variation of parameters (that is, trace impedance). 1. Vias are only used for connecting different layers of a PCB. 2. Though the...

Misalignment of the PCB layers during manufacturing only causes local variation of parameters (that is, trace impedance).

1. Vias are only used for connecting different layers of a PCB.

2. Though the sources of variation for various signature-based PCB authentication process is different, the signature extraction process is identical.

3. Change in signature due to environmental variations could be tackled by using error-correcting codes. 4. Presence of several unique signatures for a given PCB does not add any value in authentication.