From Wikipedia, the free encyclopedia
 
Cloud computing is the use of computing resources (hardware and software) that are delivered as a service over a network
(typically the Internet).
The name comes from the use of a cloud shaped symbol as an abstraction for the complex infrastructure it contains in system diagrams.
Cloud computing entrusts remote services with a user's data, software and computation.
 
Service models
Cloud computing providers offer their services according to three fundamental models:[4][47] infrastructure as a service (IaaS),
platform as a service (PaaS), and software as a service (SaaS) where IaaS is the most basic and each higher model abstracts from
the details of the lower models.
In 2012 network as a service (NaaS) and communication as a service (CaaS) were officially included by ITU
(International Telecommunication Union)as part of the basic cloud computing models, recognized service categories of a telecommunication-centric cloud ecosystem.