1.6 How does the distinction between kernel mode and user mode function as a rudimentary form of protection (security) system? It seems that any certain instruction(s) can be executed, only when the CPU is in kernel mode. At the same instance, the hardware devices could only be accessed, only when the program is executing in the kernel mode. There is a propensity that control over when interrupts could be enabled or disabled is also possible only when the CPU is in kernel mode. Therefore, the Computer Processing Unit (CPU) has very limited capability when executing in user mode. This in turn will enforce protection of critical resources. 1.8 Describe a mechanism for enforcing memory protection in order to prevent a program form modifying the memory associated with other programs? The processor could keep track of what locations are associated with each process and limit access to locations that are outside of a program's extent. By using base and limits registers and by performing a check for every memory access, information regarding the extent of a program's memory could be maintained 1.9 What are the tradeoffs inherent in hand-held computer?
1. There will be limitation of size in memory; usually in megabytes as compared to gigabytes in computer systems. 2. The speed of the processor would be very much limited, due to lesser power ability. In fact, this suggests that the Operating System has to be designed for low power consumption. 3. Assuredly lack of physical space limits the input/output capability; input method are small screen based keyboard or hand-writing recognition while small display screen for output. 1.22 Describe the differences between symmetric and asymmetric multitude processing? Asymmetric multiprocessing - In asymmetric multiprocessing (ASMP), the operating system would typically sets aside at least one or several processors for its exclusive use, remainder of the processors would run user applications. As a result, the...
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