Cloud Service Models

Cloud providers in general and Vmware in particular defines at least three typical vCloud service models.

 
  • Infrastructure as a Service IaaS
    • Flexible environment: customers have complete control over the VMs on which their applications run
    • customers are responsible for OS patching and VM maintenance
    • two services emerged from the IaaS: Desktop as a Service (DaaS) and Disaster Recovery as a Service (DRaaS)
  • Platform as a Service PaaS
    • useful for web hosting
    • stable environment
    • PaaS Providers are responsible for patching and upgrading the underlying OS, which is sometimes a slow process
    • customers can customize how their applications work
  • Software as a Service SaaS
    • are provided by SaaS Providers
    • applications must be available to customers anytime, anywhere
    • examples: Google Gmail, Zimbra
    • customers are not concerned by how these applications work
    • customers should be able to customize the look and feel of their applications

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