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Windows Management Instrumentation 

July 8 - A star of this TechEd is certainly Windows Management Instrumentation. WMI is going to become one of the hottest TLAs of the summer. WMI is Microsoft's implementation of Web-Based Enterprise Management (WBEM), which is a standardised technology for providing enterprise system managers with a standard, low-cost solution for their management needs. WMI is based on two core components: the actual WMI manager (WinMgmt.exe), the gate for programmatical access to management data, and the Common Information Model (CIM) repository, a central storage area for that management data.
    WMI is strictly tied to two other Microsoft's technologies in the area of system management: MMC and WSH. The former provides an infrastructure to build a uniform console to present management information, whereas the latter makes available scripting capabilities to access such information programmatically.

What You Get with WMI
WMI provides you with a consistent representation of the Windows 98 and Windows 2000 system, plus a COM and scripting API to interrogate them and get the information that's needed. Furthermore, you have a flexible architecture that allows third-party vendors to extend the information model to cover new devices, applications, and other enhancements by writing code modules (WMI providers). Given this, WMI sounds like a sort of Windows esperanto for system administering and information retrieval. The secret hope is that with WMI the gloomy days, when being able to access system information was a sign of power, are definitely gone.
    WMI comes with an event architecture capable of detecting and forwarding changes in the system. Once a new hardware is WMI compatible (this can be done through extensions to its WDM driver) it integrates well and can communicate with all the rest of the Windows management system. To better understand the essence of WMI, think of OLE DB. It features the same pattern, universal access to information, that you find in WMI.
    The WMI SDK comes with a few system-provided providers: Registry Provider, Windows NT Event Log Provider, Win32 Provider, SNMP Providers, and WDM Provider.

WMI and Scripting
To facilitate information retrieval, WMI supports a query language which is similar to SQL (another indirect sign that OLE DB taught a lot…):

Select TotalPhysicalMemory From Win32_LogicalMemoryConfiguration

Another script example of WMI to get all the running processes is:

Set obj = GetObject ("winmgmts:{impersonationLevel=impersonate,(Debug)}") .InstancesOf ("win32_process")

for each Process in obj
    WScript.Echo Process.ProcessId, Process.name
next

Summary
WMI is a powerful script-based service, but it can be fairly complex when you're just getting started. However, with it you can do via script pretty complicated and somewhat incredible things, such as kill processes or reboot machines. 

Dino Esposito