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Comparison between real time and time sharing operating system

Protection and security

• Protection refers to a mechanism for controlling the access of program s processes, or users to the resources defined by computer system.

• The concept of protection came with the advent of multiprogramming where several processes compete for the use of CPU.

• the purpose was to confine each users program to its assigned areaof memory so that the programs cannot interface and harm each other.

• Protection in main memory is particularly important because of address translation. The purpose of protection is to allow concurrently running process to share the common physical address space.

• Protection also ensure that only process that have gained proper authorization from the operating system can operate on memory segment , the CPU, files and other resources.

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Virtual Machine Architecture

Virtual Machine Architecture A virtual machine can exist as a standalone machine or it can exist within a vApp. A virtual machine is a software computer that, like a physical computer, runs an operating system and applications. The virtual machine consists of a set of specification and configuration files and is backed by the physical resources of a host. Every virtual machine has virtual devices that provide the same functionality as physical hardware are more portable, more secure, and easier to manage. Virtual machines can be standalone, or they can exist within a vApp. A vApp is compound object composed of one or more virtual machines as well as one or more networks. 1. Monolithic architecture 2. Layerd archtecture . 3. Virtual machine architecture 4. Exokernel architecture 5. Client server architecture 6. Micro kernel architecture The following figure ...

Micro kernel architecture

Micro kernel architecture What is Kernel? A kernel is an important part of an OS that manages system resources. It also acts as a bridge between the software and hardware of the computer. It is one of the first program which is loaded on start-up after the bootloader. The Kernel is also responsible for offering secure access to the machine's hardware for various programs. It also decides when and how long a certain application uses specific hardware. What is Microkernel? Microkernel is a software or code which contains the required minimum amount of functions, data, and features to implement an operating system. It provides a minimal number of mechanisms, which is good enough to run the most basic functions of an operating system. It allows other parts of the operating system to be implemented as it does not impose a lot of policies. Microkernels and their user environments are usually implemented in the C++ or C programming languages with a little bit of assembly. Ho...

Monolithic Architecture

Monolithic Architecture Monolith means composed all in one piece. The Monolithic application describes a single-tiered software application in which different components combined into a single program from a single platform. Components can be: Authorization — responsible for authorizing a user Presentation — responsible for handling HTTP requests and responding with either HTML or JSON/XML (for web services APIs). Business logic — the application’s business logic. Database layer — data access objects responsible for accessing the database. Application integration — integration with other services (e.g. via messaging or REST API). Or integration with any other Data sources. Notification module — responsible for sending email notifications whenever needed. Example for Monolithic Approach Consider an example of Ecommerce application, that authorizes customer, takes an order, check products inventory, authorize payment and ships ordered products. This applicat...

Real-time system

R eal-time system · In a real time operating system, a job is to be completed within the rigid time constraints otherwise job loses its meaning. · A real time system function correctly only if it returns the correct result within its time constraints · Thus, in a real-time system, the correctness of the computation not only depends upon the logical correctness of the computation but also upon the time at which the result is produced. R eal-time system In a real time system various functions like process scheduling, memory management, I/O management and file management are performed as follows : 1. Process scheduling . the real time system uses priority based pre-emptive scheduling. each process is assigned a certain level of ...

Client server architecture

Client server architecture Client - server architecture is distributed model representing dispersed responsibilities among independent computers integrated across a network. Therefore, it's easy to replace, repair, upgrade and relocate a server while client remains unaffected. Advantages of Client-Server Architecture: Organizations often seek opportunities to maintain services and quality competition to sustain its market position with the help of technologies. Deployment of client-server computing in an organization will effectively increase its productivity through the usage of cost-effective user interface, enhanced data storage, vast connectivity and reliable application services Improved Data Sharing: Data is retained by usual business processes and manipulated on a server is available for designated users (clients) over an authorized access. Integration of Services: Every client is given the opp...