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Which of the following refers to a method in which an interface defines how communication can take place betwe

Operating systems can be programmed to carry out different methods for process isolation. Which of the following refers to a method in which an interface defines how communication can take place between two processes and no process can interact with the other’s internal programming code?

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A.
Virtual mapping

B.
Encapsulation of objects

C.
Time multiplexing

D.
Naming distinctions

Explanation:
B: When a process is properly encapsulated, no other process understands or interacts with its internal programming code. When process A needs to communicate
with process B, process A just needs to know how to communicate with process B’s interface. An interface defines how communication must take place between two
processes. As an analogy, think back to how you had to communicate with your third-grade teacher. You had to call her Mrs. SoandSo, say please and thank you, and
speak respectfully to get whatever it was you needed. The same thing is true for software components that need to communicate with each other. They have to know
how to communicate properly with each other’s interfaces. The interfaces dictate the type of requests that a process will accept and the type of output that will be
provided. So, two processes can communicate with each other, even if they are written in different programming languages, as long as they know how to communicate
with each other’s interface. Encapsulation provides data hiding, which means that outside software components will not know how a process works and will not be able
to manipulate the process’s internal code. This is an integrity mechanism and enforces modularity in programming code.
A is incorrect because virtual mapping refers to how virtual to physical memory mapping takes place within an operating system. When an application needs memory
to work with, it tells the operating system’s memory manager how much memory it needs. The operating system carves out that amount of memory and assigns it to the
requesting application. The application uses its own address scheme, which usually starts at 0, but in reality, the application does not work in the physical address
space that it thinks it is working in. Rather, it works in the address space that the memory manager assigns to it. The physical memory is the RAM chips in the system.
The operating system chops up this memory and assigns portions of it to the requesting processes. Once the process is assigned its own memory space, then it can
address this portion however it needs to, which is called virtual address mapping. Virtual address mapping allows the different processes to have their own memory
space; the memory manager ensures that no processes improperly interact with another process’s memory. This provides integrity and confidentiality.
C is incorrect because time multiplexing is a technology that allows processes to use the same resources through an interleaved method. A CPU has to be shared
between many processes. Although it seems as though all applications are executing their instructions simultaneously, the operating system is splitting up time shares
between each process. Multiplexing means that there are several data sources and the individual data pieces are piped into one communication channel. In this
instance, the operating system is coordinating the different requests from the different processes and piping them through the one shared CPU. An operating system
has to provide proper time multiplexing (resource sharing) to ensure that a stable working environment exists for software and users.
D is incorrect because naming distinctions just means that the different processes have their own name or identification value. Processes are usually assigned
process identification (PID) values, which the operating system and other processes use to call upon them. If each process is isolated, that means that each process
has its own unique PID value.

One Comment on “Which of the following refers to a method in which an interface defines how communication can take place betwe

  1. joe says:

    Encapsulation provides data hiding

    Virtual mapping refers to how virtual to physical memory mapping

    Multiplexing means that there are several data sources and the individual data pieces are piped into one communication channel.

    Naming distinctions just means that the different processes have their own name or identification value.




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