Cloud Computing
Cloud computing is a general term for anything that involves delivering hosted services over the Internet.
Example: email service, Apps, Microsoft 365, Cloud storage.
These services are broadly divided into three categories:
- Infrastructure-as-a-Service (IaaS)
- Platform-as-a-Service (PaaS) and
- Software-as-a-Service (SaaS).
Cloud ServiceModels
| SERVICE MODEL | WHO USES IT | AVAILABLE SERVICES | WHY USE IT |
| SaaS | End Users Consume | Software applications such as email, word processing, and customer relation management tools | Complete business tasks that are typically performed locally on acomputer |
| PaaS | Developers and Application Managers Build | Services for creating, and testing, web server, database | Establish a common andconsistent platform for applicationdevelopment |
| IaaS | IT System Managers Host | Virtual machines, storage services, and backup services | Build a customized computing environment |
Cloud clients
- Web Browser
- Mobile Apps
- Thin Client
Deployment Models
- Private Cloud: Deploy for a single organization. For example, National Cancer Institute (NCI)
- Public Cloud: Deploy for all organizations over the internet / public network
- Community Cloud: Deploy for several organizations, that share the same mission. For example, all organizations under NIH (NCI, CIT, NIA, NIAAA etc.)
- Hybrid Cloud: Combination of any of the above
Advantages
- Accessible Everywhere-No geographical barrier
- Pay Per Use-Pay for what you need
- More economical/Cheap-Pool of resource for many people/multi-tenant
- Faster Deployment
- Disaster recovery
Disadvantages
- Compliance-Enforcement is hard, manage by different entity
- Legal-Laws vary by countries
- Data Security-Manage by different entity and delivered over the internet (CIA)
- Privacy-Delivered over the internet (Appropriate use of data)