Describe a potential attack instance when the design house is trusted in the PCB manufacturing process. Illustrate the scenario with an appropriate case study.
1. What would be an attack instance on PCBs manufactured in untrusted design houses? Describe with a relevant case study.
2. What are the possible attacks on PCBs? Explain the taxonomy of attacks with a brief description of each attack-type.
3. Describe a hardware Trojan attack instance on an insecure PCB. 5. How can a Modchip attack be mounted on a PCB? Explain elaborately.