Chapter 1 Introduction to Windows XP Professional
Learning Objectives • Describe the Windows XP family of products • Describe the major features of the Windows XP environment • Understand the Windows XP intelligent user interface • Understand the two major networking models under which Windows XP can be used • Understand the architecture of Windows XP
A simplified diagram of how data and information flows in an Operating System The User Interface Accepts data from input devices such as the mouse and keyboard Outputs information to display devices.
A simplified diagram of how data and information flows in an Operating System Application Program Interface (API) Acts as an interface for application programs, the user interface and utilities to access the internal services of the OS
A simplified diagram of how data and information flows in an Operating System The Kernel Manages memory by locating and allocating space to programs. Schedules time for programs to execute Provides communications between programs that are running Manages and arranges services and resources that are provided by other modules Controls security
A simplified diagram of how data and information flows in an Operating System File Management System Allocates and manages secondary storage space Translates file requests from their name-based form into specific I/O requests
A simplified diagram of how data and information flows in an Operating System I/O Drivers Perform the actual storage and retrieval of files I/O drivers provides control over one or more hardware devices that are part of the computer
A simplified diagram of how data and information flows in an Operating System Network Module Controls interaction between the computer and networks
Windows XP (five products) • Windows Profesional XP 64-Bit Edition • Designed to work with 64 bit processors form Intel and ADM • Released in spring 2003 • Windows XP Media Center Edition 2005 • Designed for computers that serve as multimedia operating centers • Tuned to maximize the experiences with video, audio, images, television, and CD/DVD playback.
Windows XP (five products) • Windows XP Tablet PC Edition • Designed specifically for use on Tablet PC’s. • Has improved speech and pen recognition technologies • Windows XP Home Edition • Designed specifically for stand alone home use. • Same as Windows XP professional but does not support a number of features.
Windows XP (five products) • Windows XP Professional • Designed for stand alone use or to be part of a workgroup or domain network client. • Idea client for connecting to Windows 2003 server or Windows server 2007. • The majority of the class will deal with this version of Windows.
Windows 7 Versions • Starter • Home Premium • Professional • Enterprise • Ultimate
The Windows XP Environment (major characteristics) • Plug and Play • Automatically detects presence of new hardware. • Installs the appropriate device driver.
The Windows XP Environment (major characteristics) • Multiple Processors • Supports true multiprocessing. • Will support quad core processors.
The Windows XP Environment (major characteristics) • Multitasking • Mode of CPU operation in which computer processes more than one task at a time. • Windows XP supports two type of multitasking. • Preemptive • Cooperative
The Windows XP Environment (major characteristics) • Multithreading • Individual tasks within single process space operate independently as separate execution modules called threads. • Remember a CPU can execute only one thread of code at a time. • All threads share same memory and system resources • Allows OS to execute multiple threads from single application concurrently
The Windows XP Environment (major characteristics) • Security • Protected mandatory logon system • Memory protection • System auditing • Precise controls on file and directory access
The Windows XP Environment (major characteristics) • Help and Support Services • Comprehensive Help system • Step-by-step guides • Topical and index organizations • Online help
The Windows User Interface • The Desktop • Microsoft labels this as the “user experience”
The Taskbar Running Programs Notification Area Quick Launch Media Player
Windows XP Architecture • Windows XP is a modular OS. • Modules are small software elements that cooperate to provide the systems computing and networking capabilities. • Each module consists of unique functions, code segments and system controls • The modules communicate with each other through well defined interfaces. • This modular system allow for easy expansion and patches as needed.
Windows XP Architecture • All Windows XP processes operate in one of two modes; • User mode • Kernel mode • These modes represent a certain level of system and hardware access.
Windows XP Architecture (User Mode) • An isolated portion of the system environment in which user applications execute. • Provides only mediated access to Windows XP system resources. • Any request for services must pass through the Executive Services components of the kernel mode to obtain access.
Windows XP Architecture (User Mode) • The Application Program Interface (API) supports three core environment sub-systems. • Win 32 • Win 16 • DOS. • Win 16 and DOS programs run in API’s that emulate there native environment, however WIN32 controls the interface and all I/O requests.
Windows XP Architecture • Windows XP is an object orientated operating system. • An Object is a collection of attributes with associated data values, plus a set of related services that can be performed on that object. • Objects have an existence independent of any particular process in the Windows XP environment.
Windows XP Architecture • Objects are defined by • Type – what attributes and servises they support • Instance – defines a specific entity of a certain type • An example There may be many object of the type defined as “files” but only one can have a unique combination of directory specification and file name.
Windows XP Architecture • Windows XP controls access to individual objects. • It can control which users and groups can perform particular services related to each object.
Windows XP Architecture • Part of the user mode is the security subsystem. • This subsystem is responsible for the logon process. • Works directly with the kernel mode to verify the username and password. • To obtain access to the login sequence the user must be at a locally connected keyboard.
Windows XP Architecture • In network applications the attention sequence is used. • Ctrl+Alt+Delete • This sequence can not be faked remotely, it guarantees that the login process can not be used by remote hackers to gain access to a local computer operations.
Windows XP Architecture • Logging on to Windows XP in Local Mode
Windows XP Architecture • Logging on to Windows XP when connected to a network
Windows XP Architecture (kernel mode) • The mode which controls the inner works of the Windows XP OS. • Some key element of the kernel mode stay resident in memory at all times. • Handles process priorities and process scheduling. • Provides the ability to preempt currently running processes and schedule new processes.
Windows XP Architecture (kernel mode) • The kernel mode insulates the core operating systems from the user mode subsystem. • The user application must request any access to hardware and low-level resources from the kernel mode. • Windows checks the access requests against the access permission located in the token associated with the requestor.
Windows XP Architecture (kernel mode) • This approach helps maintain control over the entire computer and protect the system from ill-behaved applications.
Windows XP Architecture (kernel mode) • The kernel mode may be divided into three subsystems; • Executive services • Kernel • Hardware abstraction layer (HAL) • These three subsystems run in privileged mode which allows direct access to all system resources.
Windows XP Architecture (Executive Services) • Executive services are the interfaces that allow the kernel and user mode to communicate. • The executive services consist of the following;
Windows XP Architecture (Executive Services) • I/O Services • Handles all operating system input and output. • This includes • Receiving requests for I/O from applications • Determining which driver is needed • Requesting that drive for the application
Windows XP Architecture (Executive Services) • The components for the I/O manager • Cache manager – handles disk caching for all file systems. • Network drivers – the software components that enable communication with the network • Device drivers – 32-bit and multiprocessor-compatible minidrivers that enable communication with devices.
Windows XP Architecture (Executive Services) • Security Reference Monitor (SRM) • Compares the access rights of the user with the access control list (ACL) associated with an individual object. • Whenever a process is launched by a user the process inherits the rights defined by the users security token.
Windows XP Architecture (Executive Services) • Internal Process Call (IPC) manager • Controls application communications with server processes such as the WIN32 subsystem. • Virtual Memory Manage • Keeps track of addressable memory spaces in the Windows XP environment • Includes physical RAM and one or more page files on disk (virtual memory).
Windows XP Architecture (Executive Services) • Process Manager • Tracks two kernel dispatch objects, processes and threads. • Responsible for creating and tracking processes and threads and cleaning up after they are no longer needed. • Plug and Play Manager • Handles the loading, unloading and configuring device drivers for Plug and Play devices. • Allows the hot-swapping of devices.
Windows XP Architecture (Executive Services) • Power Manager • Monitors and controls the use of power. • Windows Manager • Introduces a method of network-based centralized control to Window XP • File System Manager • Responsible for maintaining access and cotnrol over the file systems of the Windows XP environment. • Controls file I/O transfers fro all the file systems.
Windows XP Architecture (Executive Services) • Object Manager • Maintains object naming and security function for all system objects • It allocates the use of objects, monitors there use and removes them when no longer needed • Maintains the following system objects. • Directory objects • ObjectType objects • Link objects • Event Objects • Process and thread objects • Port objects • File objects
Windows XP Architecture • The Hardware Abstraction Layer • The goal of this layer is to isolate any hardware dependent code to prevent direct access to hardware • HAL is low-level hardware dependent code. • HAL is built during the initial installation of the OS • If significant changes are made to the OS, the HAL must be rebuilt, this may require reinstallation of the OS.
Windows XP Memory Architecture • Uses a flat 32-bit memory model • Based on a virtual memory, demand page method of addressing up to 4GB. • Demand page is the characteristic where an application can request (demand) a specific item from memory.
Windows XP Security Technologies • Windows Firewall • Security Center • Attachment Manager • Encrypting File System • Security management policies
The Help and Support Center Security Center
The Roll of Windows XP in Organizations • Workgroup networks • Domain networks