Datasheet

SYSTEM OVERVIEW
9
WWF manages objects in the .NET namespace, has a workflow engine, and supports program
code created by Visual Studio 2005. The Microsoft website for WWF is at
http://msdn2.microsoft.com/en-us/netframework/aa663328.aspx
Windows CardSpace (WCS) Formerly InfoCard, WCS is a software framework that provides
access to secure digital identity stores, and access to authentication mechanisms for verifying
logins on the Internet. CardSpace is part of the Microsoft Identity Metasystem initiative, whose
goal is to unify identities across vendors and applications.
CardSpace applications demand virtual identification cards from users, and then create a secure
token that is passed to the authentication authority users to define virtual information cards that
can be passed to applications as user queries. When the user successfully answers the questions,
the service transmits a digitally signed XML token that provides access to the application. Card-
Space resources can be found at
http://msdn2.microsoft.com/en-us/netframework/aa663320.aspx
Windows Communication Foundation (WCF) WCF is the new IPC communication stack
and was described previously under the Indigo project. WCF is a service-oriented model that
accesses the .NET namespace and that can span multiple network transport protocols, security
systems, and messaging formats. Since WCF can span different services and protocols, it can
also communicate across different topologies and architectures. Microsoft hopes to unify many
of its older web services with WCF. For more information about WCF, refer to the MSDN site at
http://msdn2.microsoft.com/en-us/netframework/aa663324.aspx
Windows Presentation Foundation (WPF) WPF is the user interface portion of the service
and was described in detail under the Avalon project. More technical information about WPF
may be found on MSDN at
http://msdn2.microsoft.com/en-us/netframework/aa663326.aspx
While all of these subsystems are APIs, they will be expressed by applications as a set of com-
mon features and functions that is enabled by Windows Server 2008 in the same sense that Active
Directory was expressed in domain and application logons and in the common management rou-
tines used for diverse hardware and software. The .NET footprint will give Windows Server 2008
and Vista a certain look and feel that is unique to this particular server and client.
Kernel Modifications
From a hardware perspective (Figure 1.5) the kernel serves the same function that a conductor in
an orchestra does. From a software perspective, the kernel is the program that interprets program
commands to determine what operations are possible and what operations are allowed. The kernel
doesn’t directly communicate with the microprocessor. Instead, the kernel passes its commands in
through to an assembler, which translates the commands into assembly or machine language, which
is the actual microcode that the microprocessor understands. Modern assemblers create object code
from assembly instructions.
Hardware I/O is made a kernel function for good reason. The kernel runs in what is called
protected mode , isolating software from hardware. Figure 1.5 shows the basic topology of the kernel.
The kernel isolates hardware from bad programs and bad programmers, and isolates good pro-
grams and good programmers from bad hardware. When a device fails, the kernel provides a
graceful recovery from catastrophic failure.
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