In Cloud computing three types of Cloud Services are available those are as follows
- Software As A Service(i.e SAAS)
- Platform As A Service(i.e PAAS)
- Infrastructure As A Service(i.e IAAS)
Software As A Service(i.e SAAS)
- By this services, application is offered to the customer.
- A single interface of the service runs on the cloud and multiple end users are serviced.
- It reduces customers cost as they do not have to invest in to multiple servers and software licenses ,while for provider reduces their cost since only single application needs to be hosted and maintained.
- Main disadvantage of this service is, generic application is not always suitable for business use.
Eg : Google docs, Microsoft office web apps tool, Pixlar, Jaycut, Aviary etc..
Platform As A Service(i.e PAAS)
- PAAS allow users to develop applications using language specific tools which is available run time on demand.
- To meet development requirements of the application, they offers a predefined combination of OS and application servers, such as LAMP platform (Linux, Apache, MySql and PHP), restricted J2EE, Ruby etc.
- It can reduce client’s development cost .
- Disadvantage of this service is only that it is available with specific language & tools only.
E.g: Google Apps Engine, Windows Azure Platform, Force.com etc
Infrastructure As A Service(i.e IAAS)
- It provides basic storage and computing capabilities as standardized services over the network like servers, storage systems, networking equipment, data center space etc and load balancer to handle work load.
- Client can also deploy their own application as well.
- IAAS With the help of virtualization, multiple users can share one physical server on low cost while for provider it reduces their cost since only single server needs to be maintained.
- Amazon, Rack space, Gogrid, 3 Tera are popular IaaS service providers.