Installation and Update Management: A User Perspective
Windows Vista® improves the familiar Windows Installer and introduces ClickOnce, a Web-based deployment technology, while coupling infrastructure and data background data transfer capabilities to make patching and system upgrades more seamless for users.
The ClickOnce Experience
ClickOnce, introduced with .NET Framework 2.0 and supported by Visual Studio® 2005, is Microsoft's easy-to-use, Web-based installation solution.
Instead of requiring access to media—a CD or downloaded file—ClickOnce enables users to obtain an application from files on a Web or a file server. Users then can click a link provided in ClickOnce to install, run, or simply start the application.
ClickOnce provides the following benefits:
Ease of deployment and security during installation, including proper application signing. ClickOnce is fully compatible with, and makes use of, the Windows Vista enhancements to security, such as User Account Control (UAC).
Reduced impact to the user's computer. ClickOnce deployments do not rely on a system's shared components or alter them. This eliminates the potential that a new application or upgrade will destabilize a running system. Likewise, it prevents modifications to other parts of the system from compromising an application's behavior that is based in ClickOnce.
Ease in obtaining upgrades. Applications deployed with ClickOnce can be configured to check automatically for new versions on the installing server.
To ensure user security, the execution of a ClickOnce-installed application is isolated, both in its disk location and its application environment, from the system as a whole.
ClickOnce allows users to install from a Web site, network share, or even local media. Developers can configure installation so that users can:
Permanently download and add applications to a local system. The Start menu is updated, and in Control Panel an Add/Remove Programs group is created.
Temporarily download and then start an application, which will be removed from the system upon application termination.
Choose to download an application permanently or temporarily.
The Windows Installer Experience
Windows® Installer is the traditional Microsoft installation solution, already familiar to most users. Windows Installer is a general and robust installation tool that supports applications in both .NET Framework 3.0, the managed programming model for Windows Vista and Win32®, the unmanaged programming model for Windows. Users will find adding applications to their system easier and more secure when using a properly constructed Windows Installer.
New Features in Windows Installer
The new and improved features in Windows Installer include:
Integration with Restart Manager to reduce the need for system restarts as part of install, uninstall, maintenance, and patching of applications
Complete integration with Windows® User Account Control (UAC), including prompting for an Administrator account and password when appropriate
Ability to apply properly signed Windows Installer Patches without requiring privilege elevation for a current, securely installed application
Support of Windows Resource Protection (WRP) to ensure that installations do not replace protected system files
For more information about Windows Installer, see "What's New in Windows Installer 4.0" in the Windows SDK.
The following important technologies have been modified or introduced in Windows Vista to improve the user's installation experience:
Background Intelligent Transfer Service (BITS)
Component-Based Servicing (CBS)
Windows Deployment Services (WDS)
Background Intelligent Transfer Service (BITS) Technology
BITS provides enhanced download and remote update transfers. Downloads of updates are more efficiently managed, with fewer system interruptions.
BITS downloads can be:
Performed as background processes
Resumable, spanning service interruptions, network disconnects, and system restarts
Monitored, paused, and cancelled
BITS technology underpins all of Microsoft's Web-based deployment strategies, and is used both by ClickOnce and Windows Update. The use of BITS generally is transparent to both users and developers.
The BITS API:
Supports asynchronous file transfer in the foreground or background
Preserves the responsiveness of other network applications
Automatically resumes file transfers after network disconnects and computer restarts
For more information on BITS, see "Background Intelligent Transfer Server" in the Windows Software Development Kit (SDK).
In addition to improved support for application installation and upgrading, Windows Vista provides a new upgrade management application from the operating system through Component-Based Servicing (CBS).
CBS is integral to Windows Vista, providing all required servicing functions, such as component updates and optional component installation, to keep the operating system more secure, reliable, and self-healing.
CBS technology provides:
Faster response time in correcting operating bugs and issues
Improved engineering efficiency
A common user interface for operating system and application servicing
Windows Deployment Services
Windows Deployment Services (WDS) is an installer application for corporate deployment and is a successor to Remote Installation Services (RIS) found in previous versions of Windows. WDS assists with the rapid adoption and deployment of Windows by enabling an administrator to set up new client computers via a network-based install, without having to visit each client directly and without having to install directly from CD/DVD media. Client installation can be controlled using an automated script or interactively, through a client User Interface. New features, such as the modularization of Windows Vista, the use of the Windows Imaging Format (WIM), and XML-based answer files and new scripting support, make this process much more flexible for the administrator and allow easier customization of client machines in organizations.
With WDS, developers can build customized Windows deployment solutions on top of an existing deployment infrastructure.