Information Technology Reference
In-Depth Information
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Image based
—Image-based deployment scenarios should be con-
sidered for extended enterprise network deployment and update,
though hardware and software variation may create the need for
multiple “images” that must be independently updated to include
emerging defensive or operational requirements. Some enterprises
may deploy fully configured operating systems complete with
necessary software applications already installed and configured,
captured as an “image” copied from a source system. Others may
employ a basic image that is then modified by additional applica-
tion customization.
Deployment can be conducted by connecting systems within a
protected “nursery” network in which systems can be configured
and updated before being exposed to a publically accessible network
with its attendant threats due to worms and other malware. Deploy-
ment may be performed over network connections to in-place
systems when network bandwidth is adequate and the network is
defended against malware. When network bandwidth is limited or
unavailable, image deployment can also be conducted using remov-
able media such as optical disks, USB memory sticks, or external
hard drive devices.
Virtualized environments may also employ a standard image for
rapid system provisioning, allowing deployment of additional virtual
systems by simply copying the source files to the new hosting loca-
tion. This practice aids support functions by minimizing variation
between virtual systems in the same way that purchasing strategies
can minimize variation between hardware systems.
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Base plus
—Medium to large enterprise networks should consider
deployment options that depend on a standard base, often only the
basic operating system and defensive applications, atop which appli-
cations are loaded based on group or location strategies reflecting
organizational functions. Deployment of applications through this
type of solution requires more detailed planning but can provide
initial deployment as well as later update functions through the
same mechanism.
In this strategy, the base operating system and OS-integrated
applications such as malware defense are captured as an image to be
deployed to all systems. After identifying the proper group member-
ship or location settings for each system within the directory ser-
