Summary
Highlights
When deploying cloud applications, consider the audience. Public clouds are suitable for internet-accessible applications, while private clouds (on-premise virtualized data centers) are for internal use. Many organizations utilize a hybrid approach combining both public and private clouds.
SaaS offers on-demand software access through a browser login. The provider manages the application, data storage, and updates, requiring no local installation or management from the user. Examples include Google Mail and Office 365, where users simply log in and use the app.
IaaS, also known as Hardware as a Service (HaaS), provides computing resources in the cloud. Users are responsible for installing, managing, and upgrading their software and data on this infrastructure. This model offers more control over data access and security, common in web service providers where users rent server time.
PaaS is a middle ground, offering cloud-based tools for application development. The provider handles the underlying engine, while the user builds and maintains customized applications using these provided building blocks. Salesforce.com is a prime example, offering tools to create custom applications on their platform.
A responsibility matrix illustrates the division of tasks between the customer and cloud provider across different cloud models. On-premise deployments make the customer responsible for everything. With IaaS, the provider manages physical infrastructure, while the customer handles applications and data. PaaS shares responsibilities like network controls and identity, with the customer managing accounts and data. SaaS offloads most responsibilities, including application management, to the provider, leaving customers primarily with account and data oversight. The choice of cloud model depends on desired infrastructure and willingness to take on responsibility.