Cloud Computing Service Types
Platform as a Service (PaaS
) is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage web applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app.[1][2][3] PaaS can be delivered in two ways: as a public cloud service from a provider, where the consumer controls software deployment and configuration settings, and the provider provides the networks, servers, storage and other services to host the consumer's application; or as software installed in private data centers or public infrastructure as a service and managed by internal IT departments.[
Software as a Service (SaaS)
Software as a service (SaaS; pronounced /sæs/ or /sɑːs/[1]) is a software licensing and delivery model in which software is licensed on a subscription basis and is centrally hosted.[2][3] It is sometimes referred to as "on-demand software".[4] SaaS is typically accessed by users using a thin client via a web browser. SaaS has become a common delivery model for many business applications, including office and messaging software, payroll processing software, DBMS software, management software, CAD software, development software, gamification, virtualization,[4] accounting, collaboration, customer relationship management (CRM), management information systems (MIS), enterprise resource planning (ERP), invoicing, human resource management (HRM), talent acquisition, content management (CM), antivirus software, and service desk management.[5] SaaS has been incorporated into the strategy of all leading enterprise software companies.[citation needed]"IBM cloud strategy". One of the biggest selling points for these companies is the potential to reduce IT support costs by outsourcing hardware and software maintenance and support to the SaaS provider.[citation needed] According to a Gartner Group estimate, SaaS sales in 2010 reached $10 billion, and were projected to increase to $12.1bn in 2011, up 20.7% from 2010.[6] Gartner Group estimates that SaaS revenue will be more than double its 2010 numbers by 2015 and reach a projected $21.3bn. Customer relationship management (CRM) continues to be the largest market for SaaS. SaaS revenue within the CRM market was forecast to reach $3.8bn in 2011, up from $3.2bn in 2010.[7] The term "software as a service" (SaaS)[8] is considered to be part of the nomenclature of cloud computing, along with infrastructure as a service (IaaS), platform as a service (PaaS), desktop as a service (DaaS), managed software as a service (MSaaS), Mobile Backend as a service (BaaS), and information technology management as a service (ITMaaS). Contents
Infrastructure
refers to the fundamental facilities and systems serving a country, city, or area,[1] including the services and facilities necessary for its economy to function.[2] It typically characterises technical structures such as roads, bridges, tunnels, water supply, sewers, electrical grids, telecommunications, and so forth, and can be defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions."[3]
