Cloudware Basics - Guide to Cloud Computing for Business and Technology Managers - page 260

13.1 Cloud Definition
Here is National Institute of Standards and Technology (NIST) working
definition:
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. This cloud model promotes avail-
ability and is composed of five essential characteristics, three delivery models, and
four deployment models.
The five essential characteristics are as follows:
1. On-demand self-service
2. Broad network access
3. Resource pooling
4. Rapid elasticity
5. Measured service
The three delivery models are as follows:
1. Infrastructure as a Service (IaaS)
2. Platform as a Service (PaaS)
3. Software as a Service (SaaS)
The four deployment models are as follows:
1. Public cloud
2. Private cloud
3. Hybrid cloud
4. Community cloud
Cloud computing is the IT foundation for cloud services and it consists of
technologies that enable cloud services. The key attributes of cloud comput-
ing are shown in Table 13.1. Key attributes of cloud services are described in
Table 13.2.
13.2 Cloud Characteristics
Large organizations such as IBM, Dell, Microsoft, Google, Amazon, and
Sun have already started to take strong positions with respect to cloud