Author name: Umar Draz

A network operating system (NOS) primarily runs on a server. It manages network resources, security, and file sharing for clients connected to the network. While individual client systems have their own operating systems to manage local resources, the NOS is centralized on the server to coordinate network-wide operations.

c) Network Operating System is the correct answer.

While there are various architectural models within distributed systems (like client-server, peer-to-peer, etc.), the overarching term for an operating system that manages a network of computers is a Network Operating System (NOS).

Incorrect options:

Zone-based Operating System: This term doesn't have a standard definition in the context of operating systems.

Level-based Operating System: This term also doesn't have a standard definition in the context of operating systems.

Therefore, Network Operating System is the most accurate and widely recognized term for an operating system that manages a distributed system.

The fork() system call is used in Unix-like operating systems to create a new process. It creates a copy of the current process, called a child process, which runs concurrently with the parent process.

Whenever a process requires input or output operations involving a disk, it initiates a system call to the operating system. This system call informs the OS about the specific I/O request, such as reading or writing data to a particular location on the disk. The OS then handles the request, interacts with the disk controller, and eventually returns control to the process when the operation is complete.

The boot loader is responsible for loading the operating system when a computer is turned on. In systems with multiple operating systems, the boot loader provides a menu or options to select the desired operating system to load.

To recover from failures in network operations, state information is crucial. This information includes details about the current status of connections, data transfers, and other relevant parameters. By maintaining state information, network protocols and applications can restore communication and resend lost data in case of failures.

For example, TCP (Transmission Control Protocol) uses sequence numbers and acknowledgments to keep track of data packets and retransmit lost ones. This state information is essential for reliable data transfer.

The operating system ignores the links when traversing directory trees. This is because links are essentially shortcuts or pointers to existing files or directories, and they don't affect the underlying directory structure. The operating system follows the actual directory paths to navigate the file system.

The operating system maintains an open-file table to keep track of information about all open files. This table contains details such as:

File pointer (current position within the file)

Access permissions

File attributes

Buffer addresses

This information is crucial for efficient file management and access.

The information about all files is kept in a separate directory structure. This structure organizes files and directories hierarchically, making it easy to locate and manage files.

This is correct.

Working set is the set of memory pages actively used by a process. If the total size of all active processes' working sets exceeds the available physical memory, the operating system faces a memory shortage.

To prevent system slowdown or crashes due to excessive page swapping (thrashing), the operating system typically suspends one or more processes. This frees up their memory frames, reducing the overall memory demand and allowing the remaining processes to continue operating efficiently.