4.5. Operating system new technology

An example of a new OS is Microsoft Windows NT, which is a high-speed 32-bit network system with a graphical interface and built-in network tools. This OS is focused on networking.

In order to make connections between remote objects using a remote access service, modems are required at both ends of the connection, printers, tape drives and other devices.

The Wndows NT operating system has the properties listed below.

1. Portability, i.e., ability to work on CISC– and RISC processors.

2. Multitasking, i.e., the ability to use a single processor to run multiple applications or threads.

3. Multiprocessing, which includes several processors that can simultaneously run multiple threads, one for each processor in the computer.

4. Scalability, i.e. the ability to automatically use the positive qualities of the added processors. For example, to speed up the operation of the application, the OS can automatically connect additional identical processors. Windows NT scalability is provided by:

• multiprocessing of local computers, i.e., the presence of several processors in them, the interaction between which occurs through shared memory;

• symmetric multiprocessing, involving the simultaneous execution of applications on multiple processors;

• distributed processing of information between several networked computers based on the remote procedure call concept, which supports the client-server architecture.

5. Client-server architecture, connecting single-user workstation and multi-user general-purpose servers (to distribute data processing load between them). This interaction has an object orientation; the object sending the message is the client, and the object receiving the message is the server.

6. Object architecture. Objects are objects of the directory, process and control threads, partition and memory segment objects, port objects. An object type includes a data type, a set of attributes, and a list of operations that can be performed on it. Objects can be managed using OS processes, i.e., through some sequence of actions that determine the corresponding program and make up the task.

7. Extensibility, which is due to an open modular architecture that allows you to add new modules to all levels of the OS. The modular architecture facilitates connectivity with other network products, and computers running Windows NT can communicate with servers and clients of other operating systems.

8. Reliability and fault tolerance, determined by the fact that the architecture protects the OS and applications from destruction.

9. Compatibility, i.e., the ability of Windows NT version 4 to support MS DOS, Windows 3.x, OS / 2 applications and to have a wide range of devices and networks.

10. Domain network architecture, which predetermines the grouping of computers into domains.

11. Multi-level security system, which was created to ensure the security of the OS, applications, information from destruction, illegal access, non-professional user actions. It works at the user level, local and network computers, domains, objects, resources, network information transfer, applications, etc.