Cloud Service ModelsThere are three main service models in the cloud. You will see these buzz words being used a lot in cloud discussions:
- IaaS - Infrastructure as a Service
- PaaS Platform as a Service
- SaaS Software as a Service
Starting from network to application
IaaS - Infrastructure as a ServiceThink of Infrastructure as a Service as Hardware to Rent. Instead of purchasing network equipment, storage space or servers you use the cloud provider’s infrastructure.
This means the cloud provider owns and maintains the housing, running and maintaining of all the hardware, not you. You will need to install the operating system and database software but you don’t have to worry about maintaining the hardware. And the cloud provider will have mechanisms in place to ensure that your hardware continues to work in the event of a failure
PaaS - Platform as a ServicePlatform as a Service can be thought of as Servers to Rent. Here the cloud provider supplies you with hardware, operating system and database server. You simply place your data in the database server and connect your application to it. You do not have to worry about patching, upgrades, failover and backups. The Cloud provider will manage all that for you. With both IaaS and PaaS you have the flexibility to use more or less storage or processing power as and when you require it.
This is attractive to business which might otherwise have to maintain large amounts of storage space just for occasional peak times.