BI-UM-3-4 Memory Protection Devices

BI-UM-3-4 part of Memory Protection Devices refer to a particular hardware module that prevents the read and write operations of user program from accessing the memory used by another user. It consists of four basic components: 1. User Identification Module (UIM): This is the main component of the protection device. It consists of a register that stores the user ID or authentication information of the user, thus enabling only valid users to access the system. 2. Access Control Module (ACM): The ACM is responsible for ensuring that valid users can only access the allocated memory blocks. It controls the read/write operations in specified memory areas and compares the user ID with the stored user ID in the UIM. 3. Memory Protection Module (MPM): The MPM is responsible for providing protection to the system memories by separating them into different address spaces. It also manages the access permissions of different users. 4. Error Detection Module (EDM): The EDM is responsible for detecting memory access errors. It checks for any illegal or out-of-bounds access attempts and takes appropriate actions to prevent any further activity from that source.