The main function of Azure OS and Windows OS is to host and run applications. But there ends the similarity. An Azure OS is a much more complex OS, while being similar with a traditional operating system in hosting and running the applications.
1. Traditional Windows OS runs in a single machine. But Azure OS is distributed among thousands of servers on Microsoft data centers.
2. In a traditional environment, Applications do not have a direct access to the hardware; all interactions must come through the kernel. Kernel is the low-level operating system component that performs all the Tasks of processing, memory management, and device management.
Cloud environment is a virtual environment. In this environment, the application will not be running in a single server. It runs on thousand of servers. Cloud operating system is not responsible for assigning resources to your applications. In Windows Azure, that responsibility is given to the fabric controller.
The fabric controller performs the functions of the kernel in a traditional OS.
A virtual environment simulates the working of an OS installed on a physical server. The benefits are you can have multiple OS environments running on a single server.
The virtual environment isolates itself from the physical server there by providing higher degree of safety and availability.
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