If you want to truly know how Windows 8 works
and what makes it tick, you need to dig under the hood. Windows 8
doesn’t boot from an initialization file. Instead, the operating system
uses the Windows Boot Manager to initialize and start the operating
system.
The boot environment dramatically
changes the way the operating system starts. The boot environment was
created by Microsoft to resolve several prickly problems related to boot
integrity, operating system integrity, and firmware abstraction. The
boot environment is loaded prior to the operating system, making it a
pre–operating system environment. As such, the boot environment can be
used to validate the integrity of the startup process and the operating
system itself before actually starting the operating system.
The boot environment is
an extensible abstraction layer that allows the operating system to work
with multiple types of firmware interfaces
without requiring the operating system to be specifically written to
work with these firmware interfaces. Rather than updating the operating
system each time a new firmware interface is developed, firmware
interface developers can use the standard programming interfaces of the
boot environment to allow the operating system to communicate as
necessary through the firmware interfaces.
Firmware interface abstraction is the first
secret ingredient that makes it possible for Windows 8 to work with
BIOS-based and EFI-based computers in exactly the same way, and this is
one of the primary reasons Windows 8 achieves hardware independence.
The next secret ingredient for Windows 8
hardware independence is Windows Imaging Format (WIM). Microsoft
distributes Windows 8 on media using WIM disk images. WIM uses
compression and single-instance storage to dramatically reduce the size
of image files. Using compression reduces the size of the image in much
the same way that zip compression reduces the size of files. Using
single-instance storage reduces the size of the image because only one
physical copy of a file is stored for each instance of that file in the
disk image.
The final secret ingredient for
Windows 8 hardware independence is modularization. Windows 8 uses
modular component design so that each component of the operating system
is defined as a separate independent unit or module. Because modules can
contain other modules, various major features of the operating system
can be grouped together and described independently of other major
features. Because modules are independent from each other, modules can
be swapped in or out to customize the operating system environment.
Windows 8 includes extensive
support architecture. At the heart of this architecture is built-in
diagnostics and troubleshooting. Microsoft designed built-in diagnostics
and troubleshooting to be self-correcting and self-diagnosing or,
failing that, to provide guidance while you are diagnosing problems.
Windows 8 includes network
awareness and network discovery features. Network awareness tracks
changes in network configuration and connectivity. Network discovery
controls a computer’s ability to detect other computers and devices on a
network.
Network awareness allows Windows 8 to
detect the current network configuration and connectivity status, which
is important because many networking and security settings depend on the
type of network to which a computer running Windows 8 is connected.
Windows 8 has separate network configurations for domain networks,
private networks, and public networks and is able to detect
-
When you change a network connection
-
Whether the computer has a connection to the Internet
-
Whether the computer can connect to the corporate network over the Internet
Windows Firewall in Windows 8
supports connectivity to multiple networks simultaneously and multiple
active firewall profiles. Because of this, the active firewall profile
for a connection depends on the type of connection.
If you disconnect a computer from one
network switch or hub and plug it into a new network switch or hub, you
might inadvertently cause the computer to think it is on a different
network, and depending on Group Policy configuration, this could cause
the computer to enter a lockdown state in which additional network
security settings are applied. As shown in Figure 6,
you can view the network connection status in the Network And Sharing
Center. In Control Panel, under Network And Internet, tap or click View Network Status And Tasks to access this management console.
Tip
Through the DirectAccess
feature, computers running Windows 8 can directly access corporate
networks wherever they are as long as they have access to the Internet,
and best of all, users don’t need to initiate VPN connections. The
feature relies on DirectAccess servers being configured on the corporate
network and DirectAccess being enabled in Group Policy.
Windows 8 tracks the identification status of
all networks to which the computer has been connected. When Windows 8
is in the process of identifying a network, the Network And Sharing
Center shows the Identifying Networks state. This is a temporary state
for a network that is being identified. After Windows 8 identifies a
network, the network becomes an Identified Network and is listed by its
network or domain name in the Network And Sharing Center.
If Windows 8 is unable to identify the
network, the network is listed with the Unidentified Network status in
the Network And Sharing Center. In Group Policy, you can set default
location types and user permissions for each network state, as well as
for all networks, by using the policies for Computer Configuration under
Windows Settings\Security Settings\Network List Manager Policies.
When you are working with the Network And Sharing Center, you can attempt to diagnose a warning status by using Windows Network Diagnostics—another
key component of the diagnostics and troubleshooting framework. To
start diagnostics, tap or click Troubleshoot Problems, tap or click
Internet Connections, and then tap or click Next. Windows Network
Diagnostics then attempts to identify the network problem and provide a
possible solution.
The Windows diagnostics and
troubleshooting infrastructure offers improved diagnostics guidance,
additional error reporting details, expanded event logging, and
extensive recovery policies. Although early versions of Windows include
some help and diagnostics features, those features are, for the most
part, not self-correcting or self-diagnosing. Windows now can detect
many types of hardware, memory, and performance issues and resolve them
automatically or help users through the process of resolving them.
Error detection for devices and failure
detection for disk drives also are automated. If a device is having
problems, hardware diagnostics can detect error conditions and either
repair the problem automatically or guide the user through a recovery
process. With disk drives, hardware diagnostics can use fault reports
provided by disk drives to detect potential failure and alert you before
this happens. Hardware diagnostics can also help guide you through the
backup process after alerting you that a disk might be failing.
Windows 8 can automatically detect
performance issues, which include slow application startup, slow boot,
slow standby/resume, and slow shutdown. If a computer is experiencing
degraded performance, Windows diagnostics can detect the problem and
provide possible solutions. For advanced performance issues, you can
track related performance and reliability data in the Performance
Monitor console, which is an administrative tool.
Windows 8 can also detect issues related to
memory leaks and failing memory. If you suspect that a computer has a
memory problem that is not being automatically detected, you can run
Windows Memory Diagnostic manually by completing the following steps:
-
From Start, type mdsched.exe, and then press Enter. Normally, text that you type on Start is entered into the Apps Search box by default.
-
Choose whether to restart the computer and
run the tool immediately or schedule the tool to run at the next
restart, as shown in Figure 7.
-
Windows
Memory Diagnostic runs automatically after the computer restarts and
performs a standard memory test. If you want to perform fewer or more
tests, press F1, use the up and down arrow keys to set the Test Mix as
Basic, Standard, or Extended, and then press F10 to apply the desired
settings and resume testing.
-
When testing is complete, the computer restarts. You’ll see the test results when you log on.
If a computer crashes
because of failing memory and Memory Diagnostic detects this, you are
prompted to schedule a memory test the next time the computer is
started.
