Page 27 - Cloud Essentials

Cloud elasticity is similar to scalability. Whereas scalability is defined
as the ability of a system to grow to accommodate need, elasticity allows

cloud customers to not only increase but also decrease the amount of IT
services consumed.

CERTIFICATION OBJECTIVE 1.02

Cloud Computing and Virtualization

Virtualization technology makes cloud computing possible, and it has been
around for decades. Providers can host many virtual machines based on
client needs without allocating a physical server to each client. Some cloud

offerings do allow clients to use physical servers, but this is costly and is
not a common approach.
Nonvirtualized computers have one set of hardware and one set of
software, as shown in Figure 1-4. Virtualization is a set of techniques for
hiding hardware resources behind software abstractions to simplify the way

in which other software or end users interact with those resources.

FIGURE 1-4 Multiple virtual machines run on a single virtualization host.

The popular press typically identifies virtualization as a category of
vendor products. However, in an enterprise, virtualization should be
understood as an integrated approach encompassing software, hardware,

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