Datasheet

22 Part I  Overview of Commerce
accounting and monitoring, user interface, service backend, and so on.
These components are collectively layered on top of infrastructure man-
agement functions and access them through a service layer.
Infrastructure management services:
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This is a service layer that exposes
the functions of the infrastructure management. This may be built specifi-
cally for the purpose of the cloud computing implementation, or could
exist only to support other use cases such as process automation.
Infrastructure management:
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A set of components that implement the
infrastructure management functions. This includes servers, hypervisors,
network, storage management, platform management, application man-
agement, monitoring, infrastructure service management, and so on.
Infrastructure:
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The infrastructure layer is composed of server and network
storage resources, implementation of infrastructure-specific services such
as log rotation services, firewall services, and key management.
Infrastructure services:
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In this context the infrastructure services are the
services that are required by the applications or other services deployed
on the infrastructure.
Cloud computing is the foundation of scalable e-commerce systems. The fol-
lowing sections delve deeper into the technical and operational details of cloud
computing, its main characteristics, and how they are implemented.
Shared Resources
One of the key requirements to increase the utility of the infrastructure is the
capability to share resources across multiple workloads. In the most favorable
scenario, the pattern of resource usage should be a non-overlapping distribution
model that allows for the greatest infrastructure utilization. The strategies to
distribute workloads on shared resources are an important aspect of maximiz-
ing the infrastructure utilization.
Dynamic Resource Allocation
Traditional resource allocation is static, using the estimated peak capacity as
the basis to calculate the allocated resources. Cloud computing allows the
resources to be allocated as needed and as the demand increases, or de-allocated
as demand decreases. The infrastructure should determine when and which
resources should be added to specific applications. Dynamic resource allocation
has the following components:
The definition of a global pool, from which all resource requests are satis-
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fied, allowing global resource optimization
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