Cloud Models
Cloud & Virtualization
Infrastructure as a service (IaaS)
● Sometimes called Hardware as a Service (HaaS)
○ Outsource your equipment
● You’re still responsible for the management and security
● Your data is out there, but more within your control
● Web server providers
Software as a service (SaaS)
● On-demand software - No local installation
○ Why manage your own email distribution or payroll?
● Central management of data and applications
○ Your data is out there
● A complete application offering
○ No development work required, i.e., Google Mail
Platform as a service (PaaS)
● No servers, no software, no maintenance team, no HVAC
○ Someone else handles the platform, you handle the
development
● You don’t have direct control of the data, people, or
infrastructure
○ Trained security professionals are watching your stuff
● Put the building blocks together
○ Develop your app from what’s available on the platform
○ SalesForce.com
Cloud deployment models
● Private - Your own virtualized local data center
● Public - Available to everyone over the Internet
● Hybrid - A mix of public and private Community
○ Several organizations share the same resources
Local and cloud resources
● On-premise
○ Your applications are on local hardware
○ Your servers are in your data center in your building
● Hosted
○ Your servers are not in your building
○ They may not even be running on your hardware
○ Usually a specialized computing environment
● Cloud
○ Entire application instances can be created and torndown
on-demand
○ Resources are available as needed
Shared resources
● Internal cloud
○ No resources are shared
○ Build your own cloud
○ Pay for everything up front
○ No ongoing costs
● External cloud
○ Share resources with a public cloud
○ Underlying infrastructure owned by a third-party
○ Cost may be metered or up-front
Cloud computing characteristics
● Rapid elasticity
○ Scale up and scale down as needed
○ Seamless to everyone
● On-demand self-service
○ Adding software, networks, servers, storage is a
○ challenge outside the cloud
○ The cloud enables instant resource provisioning
● Resource pooling
○ All of the computing power in one place
○ One large resource instead of many small resources
● Measured service
○ Costs and utilization are very closely tracked
○ Resource planning and granular chargebacks
Metered and non-metered
● Metered cloud services
○ You pay for what you use
○ Cost to upload
○ Cost to store
○ Cost to download
● Non-metered
○ You pay for a block of storage
○ No cost to upload
○ No cost to download
