cloudComputing

Cloud Computing

Five general ; characteristic of cloud systems

1. On demand self service : provision and terminate using UI/CLI without human interaction
2. Broad Network Access : available over any network and access through standard mechanisms
3. Resource Pooling : economies of scale, cheaper services
4. Rapid Elasticity : can be elastically provisioned to scale rapidly outward and inward with demand
5. Measured Service : resource usage is measured, pay for what you use

Public vs Private vs Hybrid vs Multi Cloud

• public cloud
• aws, azure, gcp
• multi-cloud
• using a combination of public cloud service providers
• private
• on-premises version of real cloud
• hybrid
• both public and private

Hybrid cloud is not public cloud + legacy on-premises

Service Models

Different levels of service models, that differ on how much of the infrastructure stack is handled by a user.

• Infrastructure as a Service (IAAS)
• facilities, infrastructure, servers, and virtualization are abstracted away
• deal with everything else
• Platform as a Service (PaaS)
• OS, Containers are further abstracted away
• Software as a Service (SaaS)
• only interact with the application