IntRodDctIoN tO CloUd cOmPutiNg A_A"

The two words in the phrase cloud computing have the following interpretations:

• Cloud :

As a noun, this is a metaphor for the Internet. and as an adjective it means pertaining to the Internet . This usage derives from the cloud symbols that represent the Internet on diagrams.

• Computing:

Any IT activity carried out by an entity:

• When using "a local server or a personal computer", which implies that the IT resources are under the exclusive control of the entity.
• To "store, manage, and process data", which implies that the data is private to the entity, in the sense that it is determined by them, even if it is accessible by others.

This means that cloud computing is a type of Internet-based computing, and it consists of every situation where the use of IT resources by an entity has all of the following characteristics:

• Access to the resources is:
  • Controlled by the entity, and restricted by them to their authorised users.
  • Delivered via the Internet to all of these users.
• The resources are:
  • Hosted by a service provider on behalf of the entity.
  • Dedicated to the exclusive use of the entity.
• Data processed by the resources is:
  • Private to the entity and its associates.
  • Entered or collected by them, or automatically produced for them.

Depending on the context, cloud computing can mean:

• Access to and use of the resources.
• The hosting and delivery service that provides this access.
• A model for enabling such access and delivery.
• The hosted resources or services themselves.
• The computing execution carried out by the services.
• Technology used for the provision of the services.