There are four types of Cloud Services Layers which can be used in combination to provide a end-to-end cloud offerings to all the customers. These main four types of offerings are
Software as a Service (SaaS) — Offers Software or Applications such as ERP, Web Application etc based on the customer demand on the Cloud. One ERP installed in the cloud can be used by different customers with all of its features.
Platform as a Service (PaaS) — Offers a complete platform with the necessary built in services for application development. Customers can customize their applications based on their requirement on the platform provided over the cloud. The examples of platforms provided in the cloud are MySQL Database, LDAP, and Oracle Solaris Studio etc.
Infrastructure as a Service (IaaS) — Offers complete hardware and software infrastructure components, such as storage, systems, Sun Management Center and Sun Identity Manager from Oracle etc. which all can be used to develop own platform or application.
Desktop as a Service (DaaS) — Offers desktops connected with the Cloud to the customers. These desktops are securely connected to the server based applications which enables all the customers to use the same applications. Customers can log into these desktops anytime using internet and access the applications based on their needs. Customers need proper access rights to access those desktops which ensure proper security and reduce risks.
First, a cloud customer or an organization should identify the appropriate cloud service or the combination of cloud services which is best suited to its business requirements. Proper number of IT resources, Knowledge about IT applications, IT budget, and Market competition are the main deciding factors behind choosing the appropriate range of Cloud Services among these four. Organizations with significant IT expertise can chose for Infrastructure as a Service (IaaS) from the Cloud services provider and build their own customized applications based on their requirement. Organizations with very low IT budget can opt for Desktop as a Service (DaaS) to use all the applications provided by the Cloud services provider.