Introduction to Windows Management Instrumentation (WMI)

There is an industry initiative that establishes management infrastructure standards and provides a way to combine information from various hardware and software management systems. This initiative is called Web-Based Enterprise Management (WBEM). WBEM is based on the Common Information Model (CIM) schema, which is an industry standard driven by the Desktop Management Task Force (DMTF).

Microsoft Windows Management Instrumentation (WMI) is an implementation of the WBEM initiative for supported Windows platforms. WMI is useful in a Windows enterprise network where it reduces the maintenance and cost of managing enterprise network components. WMI provides:

  • A consistent model of Windows operation, configuration, and status.
  • A COM API to allow access to management information.
  • The ability to operate with other Windows management services.
  • A flexible and extensible architecture allowing vendors a means of writing other WMI providers to support new devices, applications, and other enhancements.
  • The WMI Query Language (WQL) to create detailed queries of the information.
  • An API for management application developers to write Visual Basic or Windows Scripting Host (WSH) scripts.

The WMI architecture has two parts:

  1. A management infrastructure that includes the CIM Object Manager (CIMOM) and a central storage area for management data called the CIMOM object repository. CIMOM allows applications to have a uniform way to access management data.
  2. WMI providers. WMI providers are the intermediaries between CIMOM and managed objects. Using WMI APIs, WMI providers supply CIMOM with data from managed objects, handle requests on behalf of management applications, and generate event notifications.

Windows Management Instrumentation (WMI) providers are standard COM or DCOM servers that function as mediators between managed objects and the CIM Object Manager (CIMOM). If the CIMOM receives a request from a management application for data that is not available from the CIMOM object repository, or for events, the CIMOM forwards the request to the WMI providers. WMI providers supply data, and event notifications, for managed objects that are specific to their particular domain.