CertiGuide to Network+  9  Glossary

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Hardware abstraction layer (HAL)

A thin layer of software provided by the hardware manufacturer that hides, or abstracts, hardware differences from higher layers of the operating system. Through the filter provided by the HAL, different types of hardware all look alike to the rest of the operating system. This allows Windows NT and Windows 2000 to be portable from one hardware platform to another. The HAL also provides routines that allow a single device driver to support the same device on all platforms. The HAL works closely with the kernel.

A list of the devices supported by Windows 2000, available from the Microsoft Web site.

A character-based, full-screen error message displayed on a blue background. It indicates the microprocessor detected a hardware error condition from which the system cannot recover.

A set of changes to the standard configuration of devices and services (including drivers and Win32 services) loaded by Windows 2000 when the system starts. For example, a hardware profile can include an instruction to disable (that is, not load) a driver, or an instruction not to connect an undocked laptop computer to the network. Because of the instructions in this subkey, users can modify the service configuration for a particular use while preserving the standard configuration unchanged for more general uses.

A classification for similar devices. For example, Imaging Device is a hardware type for digital cameras and scanners.

A thread initiated by the Windows NT Virtual DOS Machine (NTVDM) process that interrupts every 55 milliseconds to simulate a timer interrupt.

In data communications, one segment of the path between routers on a geographically dispersed network. A hop is comparable to one “leg” of a journey that includes intervening stops between the starting point and the destination. The distance between each of those stops (routers) is a communications hop.

A local text file in the same format as the 4.3 Berkeley Software Distribution (BSD) UNIX/etc/hosts file. This file maps host names to IP addresses. In Windows 2000, this file is stored in the \%SystemRoot%\System32\Drivers\Etc folder.

A text file that takes human domain names, (CertiGuide.com) returns its IP address.

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