Which is the PRIMARY reason why Modbus over Ethernet is easy to manaqe in a...

 According to the ISA/IEC 62443-2-4 standard, a training and security awareness program should include all personnel who have access to the industrial automation and control system (IACS) or who are involved in its operation, maintenance, or management. This includes vendors and suppliers, employees, temporary staff, contractors, and visitors. The purpose of the program is to ensure that all personnel are aware of the security risks and policies related to the IACS, and that they have the necessary skills and knowledge to perform their roles in a secure manner. The program should also cover the roles and responsibilities of different personnel, the reporting procedures for security incidents, and the best practices for security hygiene. References:

ISA/IEC 62443-2-4:2015 - Security for industrial automation and control systems - Part 2-4: Security program requirements for IACS service providers1

ISA/IEC 62443 Cybersecurity Fundamentals Specialist Training Course2