關鍵字：ARM TrustZone、可信執行環境、工業控制系統、可程式邏輯控制器、即時系統、Modbus RTU、安全周邊存取;Modern industrial control systems (ICS) under the Industry 4.0 paradigm increasingly run on general-purpose computing platforms， which introduces new security and real-time performance challenges. In these environments， critical control processes must operate alongside complex， non-critical applications on a shared hardware platform， exposing the control logic to potential interference and cyber-attacks.
This thesis proposes TEE-Industry， an architecture that leverages a Trusted Execution Environment (TEE) on ARM TrustZone technology to protect ICS control loops. Unlike prior TEE-PLC designs that host the control loop at S-EL1 inside OP-TEE， TEE-Industry places the loop and its time-critical peripherals at EL3 inside ARM Trusted Firmware-A (TF-A)， eliminating the S-EL1↔EL3 context switch on each cycle and shrinking the trusted code base.
Within the TEE， a real-time scheduling mechanism and a secure peripheral access control strategy keep the control loop timely and its sensor/actuator I/O trustworthy， even if the main operating system is compromised.
Our initial evaluation on a Rockchip RK3399 platform measures a fixed software overhead of approximately 1.0 ms per cycle—about 1 % of the nominal 100 ms control period—and shows tighter round-trip variance than an equivalent Normal World baseline， providing a promising solution for secure and reliable industrial control in the era of Industry 4.0.
Keywords: ARM TrustZone， Trusted Execution Environment， Industrial Control Systems， PLC， Real-Time Systems， Modbus RTU， Secure Peripheral Access
