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Windows NT, what is this program and is it needed? WNT: the true story of Windows NT The windows nt family of operating systems are.

At the end of 1988, Microsoft appointed David Cutler to lead a new project in the field of software: Create a new Microsoft operating system for the 1990s. He assembled a team of engineers to develop the system new technology(New Technology - NT).

The original plan was to develop NT with OS/2-style user interfaces and application programming (API) interfaces, but OS/2 sold poorly and Windows 3.0 was a major and ongoing success in the marketplace. After seeing the market pressures and the challenges associated with developing and supporting two incompatible systems, Microsoft decided to change course and direct its engineers toward a single, cohesive operating system strategy. This strategy was to develop a family of Windows-based operating systems that would cover many types of computers, from the smallest laptops to the largest multiprocessor workstations. Thus, the next generation of Windows systems was called Windows NT.

Windows NT supports GUI(GUI) Windows and is also the first to be based on Windows operating system Microsoft system supporting Win32 API, 32-bit software interface to develop new applications. The Win32 API makes available to applications advanced operating system features such as multi-threaded processes, synchronization, security, I/O, and object management.

In July 1993, the first operating systems of the NT family appeared - Windows NT 3.1 and Windows NT Advanced Server 3.1.

Versions

Windows NT 3.1 (July 27, 1993)
Windows NT 3.5 (September 21, 1994)
Windows NT 3.51 (May 30, 1995)
Windows NT 4.0 (August 24, 1996)
Windows 2000 (February 17, 2000)
Windows XP (October 25, 2001)
Windows XP 64-bit Edition (March 28, 2003)
Windows Server 2003 (April 25, 2003)
Windows XP Media Center Edition 2003 (December 18, 2003)
Windows XP Media Center Edition 2005 (October 12, 2004)
Windows XP Professional x64 Edition (April 25, 2005)
Windows Fundamentals for Legacy PCs (July 8, 2006)
Windows Vista (November 30, 2006)
Windows Home Server (November 7, 2007)
Windows Server 2008 (February 27, 2008)

Windows NT Structure

Structurally, Windows NT can be represented in two parts: a part of the operating system that runs in user mode, and a part of the operating system that runs in kernel mode.

The part of Windows NT that runs in kernel mode is called the executive part. It includes a number of components that control virtual memory, objects (resources), I/O and file system (including network drivers), process interaction and partly the security system. These components interact with each other using intermodular communication. Each component calls the others using a set of carefully specified internal procedures.

The second part of Windows NT, operating in user mode, consists of servers - the so-called protected subsystems. Since subsystems cannot automatically share memory, they communicate with each other by sending messages. Messages can be transmitted both between a client and a server, and between two servers. All messages pass through the Windows NT executive. The Windows NT kernel schedules threads in protected subsystems in the same way as threads in regular application processes.

Support for protected subsystems is provided by the executive part. Her components are:

Object manager. Creates, deletes, and manages runtime objects—abstract data types used to represent system resources.
Security monitor. Establishes protection rules for local computer. Protects operating system resources, protects and registers executable objects.
Process manager. Creates and terminates, suspends and resumes processes and threads, and also stores information about them.

Virtual memory manager.

I/O subsystem. Includes the following components:
- an I/O manager that provides device-independent I/O facilities;
- file systems - NT drivers that perform file-oriented I/O requests and translate them into calls to ordinary devices;
- network redirector and network server - drivers file systems, transmitting remote I/O requests to and receiving requests from network machines;
- executive device drivers - low-level drivers that directly control the device;
- a cache manager that implements disk caching.

The execution part, in turn, relies on lower-level services provided by the NT kernel. Kernel functions include:

process planning,
handling interrupts and exceptions,
processor synchronization for multiprocessor systems,
system recovery after failures.

The kernel runs in privileged mode and is never removed from memory. The kernel can only be accessed through an interrupt.

Windows NT protected subsystems run in user mode and are created by Windows NT when the operating system boots. Immediately after creation they begin endless cycle their execution by responding to messages coming to them from application processes and other subsystems. Among the protected subsystems, a subclass can be distinguished called environmental subsystems. Environment subsystems implement operating system application interfaces (APIs). Other types of subsystems, called integral subsystems, perform the necessary operating system tasks. For example, most of the system Windows security NT is implemented as an integral subsystem, network servers are also implemented as integral subsystems.

The most important subsystem of the environment is Win32, the subsystem that provides application access to the 32-bit Windows API. Additionally, this system provides a graphical interface and manages user input/output.

Each protected subsystem operates in user mode, calling the execution system service to perform privileged actions in kernel mode. Network servers can run in either user mode or kernel mode, depending on how they are designed.

Subsystems communicate with each other by passing messages. When, for example, a user application calls some API procedure, the environment subsystem providing this procedure receives the message and executes it either by accessing the kernel or by sending a message to another subsystem. After the procedure completes, the environment subsystem sends a message to the application containing the return value. Sending messages and other activities of protected subsystems is invisible to the user.

The main tool that holds all Windows NT subsystems together is the Local Procedure Call (LPC) mechanism. LPC is an optimized version of a more general remote procedure call (RPC) tool that is used to communicate between clients and servers located on different cars networks.

The Windows NT or New Technology operating system was created by a group of developers led by Dave Cutler.

Windows NT is a 32-bit operating system with priority multitasking. The fundamental components of the operating system include security tools and a developed network service. Windows NT also provides compatibility with many other operating systems, file systems, and networks. Windows NT can function both on computers equipped with CISC processors with a complex instruction set computing, and on computers with RISC processors with a reduced instruction set computing. The Windows NT operating system also supports high-performance systems with a multiprocessor configuration.

The only thing familiar about Windows NT is its appearance. Behind the graphical user interface lies powerful new capabilities.

Tasks set when creating WindowsN.T. Windows NT is not a further development of previously existing products. Its architecture was created anew taking into account the requirements for a modern operating system. The features of the system developed based on these requirements are as follows.

Striving to provide compatibility new operating system, Windows developers NT retained the familiar Windows interface and implemented support for existing file systems (such as FAT) and various applications(written for MS-DOS, OS/2 1.x, Windows 3.x and POSIX). The developers also included in Windows NT tools for working with various network tools.

Achieved portability(portability) of a system that can now run on both CISC and RISC processors. CISC includes Intel-compatible processors 80386 and higher. RISC are represented by systems with MIPS processors R4000, Digital Alpha AXP and Pentium P54 series and higher.

Scalability(scalability) means that Windows NT is not tied to a single-processor computer architecture, but is capable of taking full advantage of the capabilities provided by symmetric multiprocessor systems. Currently Windows time NT can operate on computers with the number of processors from 1 to 32. In addition, if the tasks facing users become more complex and the demands placed on the computer environment expand, Windows NT makes it possible to easily add more powerful and productive servers and workstations to the corporate network.

Additional benefits allows the use of a single development environment for both servers and workstations.

Windows NT has a homogeneous security system(security) meeting US government specifications and complying with B2 security standard. In an enterprise environment, critical applications are provided with a completely isolated environment.

Distributed Processing(distributed processing) means that Windows NT has networking capabilities built into the system. Windows NT also allows communication with different types of host computers by supporting a variety of transport protocols and using high-level client-server facilities, including named pipes, remote procedure calls (RPC) and Windows sockets.

Reliability and fault tolerance(reliability and robustness) are provided by architectural features that protect application programs from damage to each other and the operating system. Windows NT uses fault-tolerant structured processing special situations at all architectural levels, which includes a recoverable NTFS file system and provides protection with built-in security and advanced memory management techniques.

Possibilities localization(allocation) provide tools for work in many countries of the world in national languages, which is achieved by using the Unicod standard (developed by the international organization for standardization - ISO).

Thanks to the modular design of the system, it is ensured extensibility Windows NT, which allows the flexibility to add new modules at various levels of the operating system.

The package includes a number of application programs: Internet Information Server 2.0, Index Server, FrontPage, Internet Explorer, Domain Name System (DNS) Server, Proxy Server and Internet Resource Center, all Service Packs, Plus! and a row additional utilities, including new ones, such as Administrative Wizards or Imager, and improved versions of older programs, such as Task Manager.

Administrative Wizard allows you to automate common tasks that arise when managing a network, and updated versions Windows NT Diagnostic and Performance Monitor programs are used for operational monitoring of the system state. The Task Manager dialog box has been transformed into a powerful program that provides a ton of useful information- from the degree of processor load to the names of all active system processors.

One of the key Windows components NT 4.0 - Internet Information Server 2.0. This is a flexible and multifunctional solution for both connecting to Internet networks, and to create your own private network intranet. The user only needs to configure the TCP/IP protocol parameters (if the DHCP service is installed, an IP address is assigned automatically), launch IIS and create one or more of their own Web pages. Web documents are then available to all users on your network who have software installed that supports the TCP/IP protocol and a standard World-Wide Web browser.

There have been some changes to the remote access subsystem, Remote Access Service (RAS). Now it is possible to use secure communication channels, the new Point-To-Point Tunneling Protocol (PPTP), and the ability to use several modems to organize communication channels with remote networks.

Features of the network architecture of previous versions of Windows NT (multi-level model of protection against unauthorized access, specific modular design of the system, etc.) limited its throughput when working in Fast Internet networks. In version 4.0, the algorithms for caching network requests were improved, the modules of the resource sharing subsystem were optimized, and the mechanism for generating interrupts was changed (with the transition to high-speed networks, this function unexpectedly became a source of problems for network operating systems). The second change that Microsoft points to is increased OS performance when performing graphical operations.

The combination of a powerful network OS and a graphical interface designed for unskilled users looks rather unusual. Windows NT 4.0 is not just another version of the popular operating system. It represents the basis for a new generation software products oriented to work on the Internet.

Windows NT Architectural Modules. As shown, Windows NT is a modular (more advanced than a monolithic) operating system that consists of individual, interconnected, relatively simple modules.

The main modules of Windows NT are (listed in order from the lowest level of the architecture to the highest): the level of hardware abstractions HAL (Hardware Abstraction Layer), the kernel (Kernel), the executive system (Executive), protected subsystems (protected subsystems) and environment subsystems subsystems).

virtualizes hardware interfaces, thereby ensuring that the rest of the operating system is independent of specific hardware features. This approach allows for easy portability of Windows NT from one hardware platform to another.

Core is the basis of the modular structure of the system and coordinates the execution of most basic Windows NT operations. This component is specially optimized in terms of volume and operational efficiency. The kernel is responsible for scheduling thread execution, synchronizing the work of multiple processors, and handling hardware interrupts and exceptions.

Execution system includes a set of privileged mode program constructs (kernel mode), representing the basic service of the operating system to the environment subsystems. The execution system consists of several components,

Rice. 2.32. Modular structure of Windows NT

each of them is designed to support a specific system service. Thus, one of the components - the Security Reference Monitor - functions together with protected subsystems and ensures the implementation of the system security model.

Environment subsystems are secure user-mode servers that provide execution and support for applications designed for various operating environments (various operating systems). Examples of environment subsystems include Win32 and OS/2 subsystems.

Hardware Abstraction Layer(HAL) is a software layer created by hardware manufacturers that hides (or abstracts) hardware differences from the upper layers of the operating system. Thus, thanks to the filter provided by HAL, different hardware appears similar from the operating system's point of view; the need is removed special settings operating system for the equipment used.

When creating the hardware abstraction layer, the task was to prepare procedures that would allow a single driver specific device support the functionality of this device on all platforms. HAL is aimed at a wide variety of hardware platforms with single-processor architecture; thus, each hardware option does not require a separate operating system version.

HAL routines are called both operating system (including kernel) facilities and device drivers. When working with device drivers, the hardware abstraction layer provides support for various I/O technologies (instead of the traditional focus on a single hardware implementation or the costly adaptation to each new hardware platform).

The level of hardware abstractions also allows you to “hide” the features of the hardware implementation of symmetric multiprocessor systems from other levels of the operating system.

Core(Kernel) works closely with the hardware abstraction layer. This module is primarily concerned with scheduling the processor's actions. If a computer contains several processors, the kernel synchronizes their operation in order to achieve maximum system performance.

The kernel dispatches streams(threads - control threads, which are sometimes called subtasks, branches), which are the main objects in the planned system. Threads are defined in the context of a process; a process includes an address space, a set of objects available to the process, and a set of control threads executing in the context of the process. Objects are resources managed by the operating system.

The kernel dispatches control threads in such a way as to maximize the load on the system processors and ensure priority processing of threads with higher priority. There are a total of 32 priority values, which are grouped into two classes: real-time and variable. This approach allows you to achieve maximum efficiency of the operating system.

Execution system subcomponents, such as the I/O manager and the process manager, use the kernel to synchronize actions. They also interact with the kernel for more high levels abstractions called kernel objects; some of these objects are exported within custom application program interface (API) calls.

The kernel manages two types of objects.

Dispatch objects(dispatcher objects) are characterized by a signal state (signaled or nonsignaled) and control the dispatch and synchronization of system operations. These objects include events, mutants, mutexes, semaphores, threads, timers.

Control objects(control objects) are used for kernel control operations, but do not affect scheduling or synchronization.

Control objects include asynchronous procedure calls, interrupts, power notifications, power statuses, processes, profiles.

Execution system(Executive), which includes the kernel and the hardware abstraction layer HAL, provides a common system service that can be used by all subsystems of the environment. Each service group is controlled by one of the separate components of the execution system:

Object Manager;

Virtual Memory Manager;

Process Manager;

Local Procedure Call Facility;

I/O Manager;

Security Reference Monitor.

The security monitor, together with the logon processor (Logon) and protected subsystems, implements Windows NT security model.

Top level the execution system is called System Services. Shown in Fig. 2.33 A system service is an interface between the user-mode and privileged-mode environment subsystems.

Cache manager. The I/O architecture contains a single cache manager, which performs caching for the entire I/O system. Caching is a technique used by the file system to increase efficiency.

Fig.2.33. System interface

Instead of directly writing to and reading from disk, frequently used files are temporarily stored in cache memory; thus, work with these files is performed in memory. Operations with data in memory are much faster than operations with data on disk.

The cache manager uses a file mapping model that is integrated with the virtual cache manager. Windows memory N.T. The cache manager provides a caching service for all file systems and network components that operate under the control of the I/O manager. Depending on the amount of available RAM, the cache manager can dynamically increase or decrease the cache size. When a process opens a File that was already in the cache, the cache manager simply copies the data from the cache into the virtual address space.

The cache manager supports services such as lazy write and lazy commit, which can greatly increase the efficiency of the file system. During slow write, changes are recorded in the file structure cache for faster access. Later, when CPU load is reduced, the cache manager writes the changes to disk. Slow motion recording is similar to slow motion recording. Instead of immediately marking the transaction as successful, the transferred information is cached and later written to the file system log in the background.

File system drivers. In the Windows NT I/O architecture, file system drivers are managed by the I/O Manager. Windows NT allows the use of a variety of file systems, including the existing FAT file systems. To ensure upward compatibility with MS-DOS, Windows 3.x and OS/2 operating systems, Windows NT supports FAT and HTTPS file systems.

In addition, Windows NT also supports NTFS, a new file system designed specifically for use with Windows NT. NTFS provides a number of features, including file system recovery tools, support for Unicode, long filenames, and support for POSIX.

The Windows NT I/O architecture not only supports traditional file systems, but also allows the network editor and server to function as file system drivers. From the point of view of the I/O manager, there is no difference between working with a file located on remote computer network, and working with a file on the local hard drive. Redirectors and servers can be loaded and unloaded dynamically just like any other drivers; a large number of redirectors and servers can be located on one computer at the same time.

Network drivers. The next type of drivers present as components in the I/O architecture are network drivers. Windows NT includes integrated networking capabilities and support for distributed applications. Redirectors and servers function as file system drivers and run at or below the provider interface level, where NetBIOS and Windows socket reside.

Transport protocol drivers communicate with redirectors and servers through a layer called the Transport Driver Interface (TD1). Windows NT includes the following vehicles:

Transmission Control Protocol/Internet Protocol TCP/IP, which provides the ability to work with a wide range of existing networks;
NBF is a descendant of NetBIOS Enhanced User Interface (NetBEUI) that provides compatibility with existing local computer networks based on LAN Manager, LAN Server and MS-Net;
data link control (DLC - Data Link Control), which provides an interface for access to mainframes and network-connected printers;
NWLink is an IPX/SPX implementation that provides communication with No-well NetWare.

At the bottom of the network architecture is the board driver network adapter. Windows NT currently supports device drivers that conform to the NDIS (Network Device Interface Specification) version 3.0. NDIS provides a flexible environment for exchanging data between transport protocols and network adapters. NDIS 3.0 allows a single computer to have multiple network adapter cards installed on it. In turn, each network adapter card can support multiple transport protocols for accessing various types network stations.

Windows NT Security Model- represented by a security monitor (Security Reference Monitor), as well as two other components: a logon processor (Logon Process) and secure protected subsystems.

In a multitasking operating system such as Windows NT, applications share a number of system resources, including the computer's memory, input/output devices, files, and the system's processor(s). Windows NT includes a set of security components that ensure that applications cannot access these resources without appropriate permission.

The security monitor is responsible for enforcing the proper access and control policies of a specific local security subsystem. The security monitor provides services for verifying access to objects, checking user privileges, and generating messages for both privileged mode and user mode. The Security Monitor, like other parts of the operating system, runs in privileged mode.

The Windows NT logon process requires a security login to authenticate the user. Each user must have a budget and must use a password to access that budget.

Before a user can access any computer resource from Windows NT, he must log on to the system through the logon process so that the security engine can recognize the user name and password. Only after successful authentication does the security monitor perform an access check to determine the user's right to access the object.

Resource security is one of the features provided by the security model. Tasks cannot access other people's resources (such as memory) other than through the use of special sharing mechanisms.

Windows NT also provides controls that allow the administrator to record user activity.

Windows NT Memory Management. Windows NT Workstation 3.51 is essentially a server operating system tailored for use on workstation. This results in an architecture in which absolute protection of application programs and data takes precedence over considerations of speed and compatibility. Windows NT's extreme reliability comes at a high system cost, so a fast CPU and at least 16 MB of RAM are required to obtain acceptable performance. Windows NT achieves lower memory security by eliminating compatibility with real-mode device drivers. Windows NT runs its own 32-bit NT applications, as well as most Windows 95 applications. Like Windows 95, Windows NT allows you to run 16-bit Windows and DOS programs within its environment.

Windows NT memory allocation differs from Windows 95 memory allocation. Native application programs are allocated 2 GB of special address space, from the 64 KB limit to 2 GB (the first 64 KB are completely inaccessible). Application programs are isolated from each other, although they can communicate through the Clipboard, DDE and OLE mechanisms.

At the top of each 2 GB application program block is code that is perceived by the application program as system DLLs rings 3. These are actually just call forwarding stubs called DLLs client side(client-side DLLs). When calling the majority API functions from an application program, client-side DLLs access local procedures ( Local Process Communication - LPC), which transfer the call and associated parameters to a completely isolated address space, which contains the actual system code. This server process checks the value of the parameters, executes the requested function, and forwards the results back to the application program's address space. Although the server process itself remains a process application level, it is completely protected from and isolated from the program that calls it.

Between the 2 and 4 GB marks are the low-level Windows NT system components of Ring 0, including the kernel, thread scheduler, and virtual memory manager. System pages in this area are granted supervisor privileges, which are determined by the physical ring protection circuits of the processor. This makes low-level system code invisible and unwritable to application-level programs, but results in performance degradation during transitions between rings. For 16-bit Windows applications, Windows NT implements Windows on Windows (WOW) sessions. Windows NT provides the ability to run 16-bit Windows programs individually in their own memory spaces or together in a shared address space. In almost all cases, 16- and 32-bit Windows applications can communicate freely using OLE (via special thunks if necessary) regardless of whether they are running in a separate or shared memory. Native WOW applications and sessions run in preemptive multitasking based on individual thread control. Multiple 16-bit Windows applications in a single WOW session run using a cooperative multitasking model. Windows NT can also multitask multiple DOS sessions. Because Windows NT has a fully 32-bit architecture, there are no theoretical limits on GDI and USER resources.

Key differences in Windows 2000. Windows 2000 or W2k is a Microsoft operating system (OS) based on Windows NT technology, which was reflected in the original name of the W2k project - Windows NT 5.0. Windows 2000 is a fully 32-bit OS with priority multitasking and improved memory management. The W2k project is based on the same principles that once ensured the success of NT.

W2k interface similar to the interface of Windows 98 with IE 5.0 installed. However, we will still note some details.

The first thing that catches your eye is that the color scheme has changed. It now resembles one of the designs used in the KDE desktop for Linux. Another noticeable detail is the shadow under the mouse cursor, which can be removed/set in Control panel -> Mouse -> Pointers, by checking Enable pointer shadow. In addition, a new effect has been added when menus appear; now they gradually appear out of thin air. Controlled from Desktop Properties, on the Effects tab, check the Use transition effects for menu and tooltips.

The Start Menu has introduced a function familiar from Office 2000, when when opened, only the most frequently used items are shown, the rest are opened if you press the down arrow. You can control this effect in Taskbar Properties, in the General tab, check Use Personalized Menus (similarly, in 1E5 this option is disabled in Tools -> Internet Options -» Advanced -> Enable Personalized Favorites Menu). There are several more items in Desktop Properties, including Hide keyboard navigation indicators until I use the Alt key. If it is selected, the underline under the letters that indicate Keyboard shortcut in Windows programs, until pressed .

On the second tab of the Taskbar Properties, Advanced, there is a Start Menu Settings window, which allows you to add/remove lines included in the Start Menu and expand some items. For example, if you check the Expand Control Panel checkbox, then when you hover the mouse cursor over the Control Panel in the Start Menu, another menu will open to the right of it, which will contain all the elements included in it. A useful feature on this tab is the Re-sort button. W2k, by default, places folders with the latest installed programs at the very bottom of the Start Menu; folders may even be below links to files. Re-sort eliminates this injustice and arranges all folders from top to bottom in alphabetical order. However, the same effect can be achieved by right-clicking in Start Menu -> Programs and selecting Sort by name. In addition, with the right button you can “drag and drop” any elements from there to any place.

Another difference that often fails people who have previously worked with NT and W9x, oddly enough, is the widespread use of Checkboxes - Especially those that are just a square on a white background. So if you find that you cannot do something, then look through all the windows again, perhaps you simply did not pay attention to such a Checkbox.

Task Manager is one of the most powerful and convenient tools in NT designed for managing processes. It is called either , or by selecting it from the menu that appears after right-clicking on the Taskbar. You can select it after .

Task manager consists of three tabs - Performance, Processes, Applications. Let's start with Performance. This tab shows information about the load of the processor(s) in real time, shows the load of physical memory, and shows how much RAM is used/free and how much system Swap is occupied. In addition, other additional information is also given there, for example Threads and Processes - the number of threads and processes currently running on the machine, Peak - the peak Swap size during the session, Nonpaged - the amount of memory allocated for the kernel. This information can be used when it comes to answering the question of what factor in the system is the “bottleneck” that slows down work (although it is better to use Performance Monitor for these purposes).

The second tab, Processes, contains a list of currently active processes. For each process, you can find out some additional information, such as: PID (Process ID), the amount of RAM used, the number of threads generated by the process, and much more. You can add/remove displayed parameters via View -> Select Columns. In addition, certain actions can be performed with any of these processes. To do this, you just need to right-click on it, a context menu will appear through which you can end the process, End Process, you can “kill” the process itself and all the others that it “spawned”, End Process Tree. You can set the priority of the process, from the highest RealTime to the lowest, Low. If the machine has two processors and a multiprocessor core, then another item appears in this menu, Set Affinity, which allows you to transfer the process to another processor, Cpu 0, Cpu l, and so on up to Sri31.

The last tab of Task Manager - Applications, allows you to view the list of running applications and terminate any of them. Task Manager not only allows you to terminate applications, it can also start new applications. File -> New task (Run).

Active Directory - This is a new tool for managing users and network resources. It is designed to make the work of administrators of large W2k-based networks easier, and the entire network management and security system is built around it. To install Active Directory you must have W2k Server. W2kPro can work in an Active Directory environment, but cannot create one. Active Directory is built on the following principles:

1. Single sign-on on the network. Thanks to IntelliMirror technology, you can go to any computer in the office and enter your password

and in front of you will be your desktop, your documents and your settings.

2. Information security. Active Directory has built-in user authentication capabilities. For each object on the network, you can centrally set access rights, depending on groups and specific users. With Kerberos security, you can communicate securely even over open networks such as the Internet. In this case, data transmitted over the network is encrypted, and passwords are not transmitted or stored on client machines. The Kerberos security system (named after the mythical three-headed dog, which, according to Greek mythology, guarded the gates of hell) has been known for quite some time, but it is used for the first time in Microsoft's OS. Without going into details, this system works like this:

The client sends a request to the authentication server for permission to access the required information;

The server checks the client's rights and sends him permission to receive the required information, encrypted using a key known to the client, and at the same time sends a temporary encryption key. All transmitted information is encrypted using this key, and the lifetime of the key is limited, so the authentication server from time to time sends a new key (naturally, the new key is encrypted using the current key), which is unknown to anyone except the server and the client. Regularly changing encryption keys makes life much more difficult for attackers hunting for your data.

However, as we all remember, in the Greek myth, Kerberos could not resist the mighty Hercules. So in our case, despite all its advantages, the Kerberos security system cannot withstand all types of attacks. For example, it is possible to bombard an application with false requests, a so-called Deny of Service attack, which can cause the application to not use the Kerberos protocol.

3. Centralized management. When using Active Directory, the administrator no longer has to manually configure each machine if, for example, it is necessary to change access rights to a single object or install a new network printer. Such changes can be made immediately for the entire network.

4 . Flexible interface. Directory structures change quickly and easily. For example, you can create a directory of your company, separate accounting, marketing departments, and secretariat into separate subdirectories and present all this in the form of a tree structure. Or, for example, create several trees representing different offices in different buildings or regions and easily set the connection and access rights between them. Connect a network printer to the accountants' directory with one mouse click. (In this case, the drivers will be installed on these computers automatically.) Or drag and drop the entire accounting department from one server to another, with all their rights, folders and documents.

5. Integration with DNS. Thanks to Active Directory's tight integration with DNS, the local network uses the same resource names as the Internet, resulting in less confusion and better interoperability between the local network and the wide area network.

6. Scalability. Multiple Active Directory domains can be combined together under one management.

7. Easy to search. In an Active Directory domain, various objects can be found based on a variety of characteristics, such as the user or computer name, user email address, etc.

DFS (Distributed File System)- one of the Active Directory tools. It allows you to create network shares that can include multiple file systems on different machines. For an Active Directory user, this is absolutely transparent and does not matter where and on which machines the files with which he works are physically located - for him they are all located in one place. In addition, when using DFS and Active Directory, managing such resources is simplified. It is centralized, you can simply and painlessly add new resources or delete old ones, change the physical location of files included in DFS, etc.

WindowsNT

Windows NT is a line of operating systems (OS) produced by Microsoft Corporation and the name of the first versions of the OS.

Windows NT was developed after the end of cooperation between Microsoft and IBM on OS/2, developed separately from other operating systems of the Windows family (Windows 3.x and Windows 9x) and, unlike them, was positioned as a reliable solution for workstations (Windows NT Workstation) and servers (Windows NT Server). Windows NT gave rise to a family of operating systems, which includes: Windows NT itself, Windows 2000, Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012

Architectural modulesWindowsNT

The Windows NT architecture is modular and consists of two main layers - user-mode components and kernel-mode components. Programs and subsystems running in user mode have restrictions on access to system resources. Kernel mode has unrestricted access to system memory and external devices. The NT system kernel is called a hybrid kernel or macrokernel. The architecture includes the kernel itself, the hardware abstraction layer (HAL), drivers and a number of services (Executives) that operate in kernel mode (Kernel-mode drivers) or in user mode (User-mode drivers).

Windows NT user mode consists of subsystems that pass I/O requests to the appropriate kernel mode driver through an I/O manager. There are two subsystems at the user level: the environment subsystem (runs applications written for different operating systems) and the integrated subsystem (manages special system functions on behalf of the environment subsystem). Kernel mode has full access to the computer's hardware and system resources. And it also prevents access to critical areas of the system by user services and applications.

Differences between Windows 2000 and NT 4.0

Some of the most significant improvements in Windows 2000 over Windows NT 4.0 are:

Active Directory directory service support. The Active Directory server side comes with Server, Advanced Server, and Datacenter Server editions, while full client-side service support is provided by the Professional edition.

Internet Information Services version 5.0. Compared to IIS 4.0, this version includes, among other things, version 3.0 of the ASP web programming system.

File system NTFS version 3.0 (also called NTFS 5.0 in the internal version of Windows 2000 - NT 5.0). In this version of NTFS, support for quotas appeared for the first time, that is, restrictions on the maximum volume of stored files for each user.

Updated user interface, including Active Desktop based on Internet Explorer version 5 and thus similar to the interface of Windows 98. The color scheme has been redesigned.

Language integration: Previous versions of Windows came in three flavors - European languages (single-byte characters, left-to-right only), Far Eastern languages (multi-byte characters), and Middle Eastern languages (right-to-left with contextual letter variations). Windows 2000 combines these capabilities; all its localized versions are made on a single basis.

EFS encrypted file system, which can be used to encrypt files and folders.

Key FeaturesWindowsXP

The Microsoft Windows XP operating system is based on NT technology and is a direct successor to the Windows 2000 system. However, all the best innovations included in Windows Me can be found in Windows XP. While maintaining high levels of reliability, security and performance, the system has become easier to learn, and many tools have appeared in it designed for individual home users.

The system is available in several versions, tailored to different application features. Microsoft Windows XP Home Edition is intended for individual users, most often working on a home computer. In this version, special emphasis is placed on working with drawings, audio and video. The Microsoft Windows XP Professional version is intended, as the name suggests, for professionals. This version is most commonly used in organizations. If you do complex work at home, such as creating and editing images, modeling and design, or any other complex work, then this version is suitable for your home computer. The Microsoft Windows XP Server version is intended for installation on a server - a powerful computer that allows multiple users to work on a computer network. Working on local networks is beyond the scope of this book, so we will not consider the server version. The book describes the main version of the operating system - Windows XP Professional. The version of Windows XP Home Edition is practically no different from it. Any minor differences will be specifically noted.

It should be noted that to work effectively with the Windows XP operating system, you need a fairly powerful modern computer. First of all, your computer must have at least 128 megabytes of memory installed. It is better to install 256 megabytes to make the system run faster. Any processor can be used, but not too old. If the processor clock speed is at least 300 megahertz, then it will be suitable. Although it is better, of course, to use a processor with a frequency of more than one gigahertz. The hard drive must accommodate not only the operating system files and temporary files, but also have enough free space, for example, to create an image of a CD before burning it. In reality, a disk size of at least two to three gigabytes is required. And if you consider that you need to install other programs on the disk and leave space for various documents, then a 10 gigabyte disk cannot be called too large.

In the version of Windows XP, the appearance of the system has changed greatly. Buttons, icons, panels now look a little different. Even the Windows main menu has changed. The interface changes are the most significant since the transition from Windows 3.1 to Windows 95. However, it is possible to use the old interface if you are used to it. Of particular note is the operation of programs in compatibility mode with previous versions of Windows. You can work with a program that is written for Windows 95, and does not work in Windows 2000. All versions of Windows XP have many innovations. A much wider variety of devices are supported. The system allows you to easily and conveniently process videos, photographs, drawings, music and songs. Now, using Windows XP, anyone can build a home network based on two or three computers, sharing files, folders, printer, fax and Internet access.

When working with Windows XP, you don't need to install additional programs to burn information to recordable and rewritable CDs. You can burn a CD directly from Windows Explorer. By the way, the conductor has changed a lot. In addition to support for compressed folders, special folders for storing pictures, music and videos, a panel has been added with commands, the composition of which changes depending on the actions you perform.

A useful component of the system is the video editor. Now you can perform professional non-linear editing of your amateur films. It has become much easier to work with digital cameras and scanners. You don't need any additional software to enter a photo into your computer, slightly transform it, and print it out. The universal audio and video player now supports more formats and allows you to change its appearance. You can create your own audio files in the popular MP3 format. The universal player also supports digital video disc (DVD) playback, allowing you to enjoy the highest quality picture and sound when watching today's movies. For entertainment, Windows XP includes several new games, some of which allow you to play online.

System security has also been significantly improved. Now, if you accidentally delete important system files, they will be automatically restored. It is possible to restore the system to an earlier state after installing new programs and equipment. Improved support for Plug & Play technology allows you to connect many modern household appliances to your computer.

Tools for working with the Internet have also received further development. The help system has been significantly redesigned and the security system has been improved. Numerous changes have affected the means of administration and management of the work of many users on a local computer network.

There are many other innovations in the system that you will learn about as you read the book and get to know Windows XP. However, before you start working with the system, we recommend that you become familiar with the basic concepts used in Windows XP. If you are familiar with previous versions of Windows, most of the concepts will be familiar to you.

WindowsVista

Windows Vista is an operating system in the Microsoft Windows NT family, a line of operating systems used on consumer personal computers. At the development stage, this operating system was codenamed “Longhorn”.

In the Windows NT product line, Windows Vista is version 6.0 (Windows 2000 - 5.0, Windows XP - 5.1, Windows Server 2003 - 5.2). The abbreviation "WinVI" is sometimes used to refer to "Windows Vista", which combines the name "Vista" and the version number written in Roman numerals.

Windows Vista, like Windows XP, is a client-only system. Microsoft also released a server version of Windows Vista - Windows Server 2008.

On November 30, 2006, Microsoft officially released Windows Vista and Office 2007 for enterprise customers. On January 30, 2007, sales of the system began in the CIS for ordinary users.

According to web analytics from W3Schools, as of October 2012, Windows Vista's market share is ▼ 3.0%; this value peaked at 18.6% in October 2009.

Windows 7

Windows 7 is an operating system in the Windows NT family, following Windows Vista. The next system after Windows 7 in the Windows 8 line. In the Windows NT line, the system has version number 6.1 (Windows 2000 - 5.0, Windows XP - 5.1, Windows Server 2003 - 5.2, Windows Vista and Windows Server 2008 - 6.0). The server version is Windows Server 2008 R2, the version for integrated systems (built from Windows components) is Windows Embedded Standard 2011 (Quebec), the mobile version is Windows Embedded Compact 2011 (Chelan, Windows CE 7.0).

The operating system went on sale on October 22, 2009, less than three years after the release of the previous operating system, Windows Vista. Partners and clients with a Volume Licensing license were granted access to RTM on July 24, 2009. The original installation images of the final version of the system have been available on the Internet since July 21, 2009.

According to web analytics from W3Schools (English), as of October 2012, the share of Windows 7 among the operating systems used in the world for accessing the Internet was ▲ 56.8%. By this criterion, it is in first place, surpassing the previous leader - Windows XP - in August 2011.

File systemNTFS

NTFS (from the English New Technology File System - “new technology file system”) is the standard file system for the Microsoft Windows NT family of operating systems.

The HPFS file system was first used for the OS/2 1.2 operating system to provide access to the large disk drives that were appearing on the market at the time. In addition, there is a need to expand the existing naming system, improve organization and security to meet the growing needs of the network server market. The HPFS file system supports the FAT directory structure and adds sorting of files by name. The file name can contain up to 254 double-byte characters. A file consists of "data" and special attributes, which creates additional opportunities to support other types of file names and improve security. In addition, the smallest block for storing data is now equal to the size of the physical sector (512 bytes), which reduces wastage of disk space.

NTFS replaced the FAT file system used in MS-DOS and Microsoft Windows. NTFS supports a metadata system and uses specialized data structures to store file information to improve performance, reliability, and disk space efficiency. NTFS stores information about files in the Master File Table (MFT). NTFS has built-in capabilities to limit access to data for different users and user groups (Access Control Lists (ACLs)), as well as assign quotas (restrictions on the maximum amount of disk space occupied by certain users). NTFS uses the USN journaling system to improve file system reliability.

NTFS is developed on the basis of the HPFS file system (High Performance File System), created by Microsoft together with IBM for the OS/2 operating system. But, having received such undoubtedly useful innovations as quotas, logging, access control and auditing, it has largely lost [source not specified 242 days] the very high performance of file operations inherent in its ancestor (HPFS).

There are several versions of NTFS: v1.2 is used in Windows NT 3.51 and Windows NT 4.0, v3.0 comes with Windows 2000, v3.1 comes with Windows XP, Windows Server 2003, Windows Server 2003 R2, Windows Vista, Windows 7 and Windows Server 2008, Windows Server 2008 R2.

File system specifications are proprietary. This creates certain difficulties when implementing its support in third-party products that do not belong to Microsoft - in particular, developers of drivers for free operating systems have to reverse engineer the system.

HPFS file system directory entries contain more information than FAT. Along with file attributes, information about creation and modification, as well as the date and time of access, is stored here. HPFS file system directory entries point to FNODE rather than to the first cluster of the file. FNODE may contain file data, pointers to file data, or other structures pointing to file data. HPFS tries to place file data in contiguous sectors whenever possible. This results in increased speed of sequential file processing. HPFS divides the disk into blocks of 8 MB each and always tries to write a file within the same block. For each block, 2 KB is reserved for the allocation table, which contains information about the written and free sectors within the block. Blocking leads to improved performance because the disk head must return not to the logical beginning of the disk (usually cylinder zero) but to the allocation table of the nearest block to determine where to save the file. Additionally, the HPFS file system contains two unique data objects.

Hello everyone, I’ll say right away that Windows NT is not really a program, it’s the Windows family from Microsoft. The name Windows NT hides the concept of operating systems from Microsoft, not just any specific one, but all systems. Windows is a very popular operating system today, and there is nothing more popular than it. My opinion is that the popularity is primarily due to the fact that there is no worthy alternative and there never will be - it’s stupid to compete with the giant Microsoft now.

But nevertheless, everything is true - you can actually have something that will be called Windows NT, because this name appears in many places. I won’t give exact examples, I don’t remember, but you can easily see this inscription in your Windows.

If you are faced with the question of whether to remove Windows NT software or not, then I will answer this way - it is better not to remove it. Because there may be problems later. Logically, if you think about it, it becomes clear that everything where Windows NT is written, you should uninstall it only when you are absolutely sure of it.

Windows NT was developed in the 1990s, after Microsoft stopped working with IBM (oh, they made cool laptops), together these companies developed OS/2, it was also an operating system that was still unclear to me, but no matter. In short, then they started cutting Windows and you know what came out of it - mega cool Windows, one monopoly, no one likes it, but everyone uses it

Yes, there is also Linux, but alas, it is for a narrow circle of users - not at all for those who need something simple and beautiful and uncomplicated. I personally like Windows, although many people didn’t like it for some reason, especially Windows 10, but I don’t see anything crooked in it..

Ancient Windows, once upon a time this was a masterpiece and the ultimate dream:

But compare, this is already seven, that is, Windows 7, many are still sitting on it and are not going to get off:

I was a fan of Windows XP for a long time, even for a very long time, I sat there for a long time - Windows 7 had already come out, and I was hanging out on XP... And so I bought new hardware, it was a 1150 socket, everything was new, but I managed to install Windows XP on it and I I still sat there for about two years. Then Windows 10 came out, and I eventually switched to it. The computer has been working for weeks and everything is fine, there are no glitches or blue screens, no errors. Everything works like clockwork. True, this was almost not the case in XP either. So somehow everyone likes Windows...

I wrote a list where exactly you can notice something like Windows NT:

descriptions of some system files;
Windows settings, system settings, Windows NT can be found everywhere there;
in reference materials for the program or even in instructions for some equipment;
It is unlikely, but it is possible that some kind of virus will affect Windows NT;
in system folders, for example in C:\Windows, there is a bunch of junk, the description of which includes Windows NT;

I completely forgot to write, I can’t say for sure myself, but it seems that there is an operating system itself called Windows NT, here is its boot screen.

At the end of 1988, Microsoft tasked David Cutler with leading a new software project: creating Microsoft's new operating system for the 1990s. He assembled a team of engineers to develop a New Technology (NT) system.

Windows NT supports the Windows graphical user interface (GUI) and is also the first Windows-based Microsoft operating system to support the Win32 API, a 32-bit programming interface for developing new applications. The Win32 API makes available to applications advanced operating system features such as multi-threaded processes, synchronization, security, I/O, and object management.

In July 1993, the first operating systems of the NT family appeared - Windows NT 3.1 and Windows NT Advanced Server 3.1.

Versions

Windows NT 3.1 (July 27, 1993)
Windows NT 3.5 (September 21, 1994)
Windows NT 3.51 (May 30, 1995)
Windows NT 4.0 (August 24, 1996)
Windows 2000 (February 17, 2000)
Windows XP (October 25, 2001)
Windows XP 64-bit Edition (March 28, 2003)
Windows Server 2003 (April 25, 2003)
Windows XP Media Center Edition 2003 (December 18, 2003)
Windows XP Media Center Edition 2005 (October 12, 2004)
Windows XP Professional x64 Edition (April 25, 2005)
Windows Fundamentals for Legacy PCs (July 8, 2006)
Windows Vista (November 30, 2006)
Windows Home Server (November 7, 2007)
Windows Server 2008 (February 27, 2008)

Windows NT Structure

Structurally, Windows NT can be represented in two parts: a part of the operating system that runs in user mode, and a part of the operating system that runs in kernel mode.

The part of Windows NT that runs in kernel mode is called the executive part. It includes a number of components that manage virtual memory, objects (resources), input/output and the file system (including network drivers), process communication, and partly the security system. These components interact with each other using intermodular communication. Each component calls the others using a set of carefully specified internal procedures.

Support for protected subsystems is provided by the executive part. Its components are:

Object manager. Creates, deletes, and manages runtime objects—abstract data types used to represent system resources.
Security monitor. Sets protection rules on the local computer. Protects operating system resources, protects and registers executable objects.
Process manager. Creates and terminates, suspends and resumes processes and threads, and also stores information about them.

Virtual memory manager.

I/O subsystem. Includes the following components:
- an I/O manager that provides device-independent I/O facilities;
- file systems - NT drivers that perform file-oriented I/O requests and translate them into calls to ordinary devices;
- network redirector and network server - file system drivers that transmit remote I/O requests to network machines and receive requests from them;
- executive device drivers - low-level drivers that directly control the device;
- a cache manager that implements disk caching.

The execution part, in turn, relies on lower-level services provided by the NT kernel. Kernel functions include:

process planning,
handling interrupts and exceptions,
processor synchronization for multiprocessor systems,
system recovery after failures.

The kernel runs in privileged mode and is never removed from memory. The kernel can only be accessed through an interrupt.

Windows NT protected subsystems run in user mode and are created by Windows NT when the operating system boots. Immediately after their creation, they begin an endless cycle of execution, responding to messages coming to them from application processes and other subsystems. Among the protected subsystems, a subclass can be distinguished called environmental subsystems. Environment subsystems implement operating system application interfaces (APIs). Other types of subsystems, called integral subsystems, perform tasks required by the operating system. For example, most of the Windows NT security system is implemented as an integral subsystem; network servers are also implemented as integral subsystems.

The main tool that holds all Windows NT subsystems together is the Local Procedure Call (LPC) mechanism. LPC is an optimized version of a more general tool, remote procedure call (RPC), which is used to communicate between clients and servers located on different machines on a network.

25.11.2020

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