PERA Level 2 & 3 Technology Overview and Compromise GICSP Practice Questions (Page 2)

Questions 6–10

1. 6application · medium

   A manufacturing plant has a Level 2 HMI that is used to start and stop a conveyor belt. The HMI is connected to the plant's Wi-Fi network for convenience. An attacker on the Wi-Fi network sends crafted packets to the HMI. What is the most effective mitigation?

   • AEnable WPA2 encryption on the Wi-Fi network.
   • BChange the HMI's default password to a strong password.
   • CRemove the HMI from the Wi-Fi network and connect it only to the wired control network.
   • DInstall antivirus software on the HMI.
   Reveal Solution Discussion Select an answer first
2. 7application · medium

   A refinery has a Level 2 HMI that is compromised by a worm that spreads through the control network. The worm causes the HMI to display false process readings. What is the most significant operational impact?

   • AOperators may make incorrect decisions based on false data, leading to unsafe conditions.
   • BThe historian will store incorrect data, affecting long-term analysis.
   • CThe corporate network will be infected, causing business disruption.
   • DThe PLCs will stop executing their control logic.
   Reveal Solution Discussion Select an answer first
4. 8application · medium

   A technician needs to troubleshoot a valve position issue from a control room. The HMI shows the valve is open, but the field device reports it is closed. What is the most likely cause?

   • AThe historian has overwritten the valve data
   • BThe valve is physically stuck and the HMI is correct
   • CThe MES system has changed the valve setpoint
   • DThe HMI is displaying stale or incorrect data due to a communication issue with the PLC
   Reveal Solution Discussion Select an answer first
5. 9foundation · easy

   Which of the following is a primary function of a Human-Machine Interface (HMI) at PERA Level 2?

   • AManaging the site-wide production schedule and inventory levels
   • BExecuting control logic directly on field sensors
   • CProviding operators with a graphical view of the process and allowing them to issue supervisory commands
   • DStoring years of historical production data for enterprise reporting
   Reveal Solution Discussion Select an answer first
6. 10foundation · easy

   In the PERA model, what is the role of the control network (often called the 'control bus') in data flow between Level 2 and Level 3?

   • AIt is the wireless network used for remote operator access.
   • BIt connects field devices directly to the enterprise network.
   • CIt provides the physical and logical path for data exchange between Level 2 supervisory systems and Level 3 site-level servers.
   • DIt is used exclusively for safety system communications.
   Reveal Solution Discussion Select an answer first