Specifications

2 Cloud Computing Standards
Cloud computing is a model for enabling convenient, on-demand network access to a shared
pool of configurable computing resources (e.g., networks, servers, storage, applications, and
services) that can be rapidly provisioned and released with minimal management effort or
service provider interaction. The following definitions have been proposed by NIST
ii
A cloud consumer can unilaterally provision computing capabilities, such as server time and
network storage, as needed automatically without requiring human interaction with each
service’s provider.
Resource Pooling serves multiple consumers using a multi-tenant model, with different
physical and virtual resources dynamically assigned and reassigned according to consumer
demand. There is a sense of location independence in that the customer generally has no
control or knowledge over the exact location of the provided resources but may be able to
specify a location at a higher level of abstraction (e.g., country, state, or data center).
Examples of resources include storage, processing, memory, network bandwidth, and virtual
machines.
Elasticity enables the ability to automatically and quickly scale out resources and rapidly
release those resources to quickly scale in. To the consumer, the capabilities available for
provisioning often appear to be unlimited and can be purchased in any quantity at any time.
Cloud systems automatically control and optimize resources used by leveraging a metering
capability at some level of abstraction appropriate to the type of service (e.g., storage,
processing, bandwidth, and active user accounts). This model of Measured Service allows
resource usage to be monitored, controlled, and reported providing transparency for both the
provider and consumer of the used service.
Infrastructure as a Service (IaaS) is where the cloud consumer generally has broad
freedom to choose the operating system and development environment to be hosted.
Security provisions beyond the basic infrastructure are carried out mainly by the cloud
consumer.
When using the IaaS model, the cloud provider maintains the storage, networking and the
hosting environment for the virtual machines. This eliminates the need for cloud consumers to
evaluate, maintain and support the hardware infrastructure.
Platform as a Service (PaaS) gives the Cloud Consumer control over applications and
application environment settings of the platform. Security provisions are split between the
cloud provider and the cloud consumer. This scenario would be beneficial for organizations
that need to develop, test, deploy and manage the application life cycle.
Software as a Service (SaaS) abstracts the management and control of the underlying cloud
infrastructure and individual applications, except for preference selections and limited
administrative settings. Security provisions are carried out mainly by the cloud provider. An
example usage model here might be a cloud consumer that simply needs access to cloud
resources for business operations. In this scenario, the cloud provider installs, manages,
7 www.redhat.com