Cloud computing lets you rent computing power, storage and software over the internet instead of buying and running your own servers. Virtualization is the underlying technology that makes the cloud possible: it slices one powerful physical machine into many isolated virtual machines. Together these two topics dominate the "Emerging Technology" portion of BCS, Bank IT-officer and other government IT exams, and questions here are often direct one-liners (Which is an example of IaaS? Which hypervisor is bare-metal? What does SaaS mean?). Master this lesson and you can answer almost every cloud MCQ with confidence.
Learning objectives
- Define cloud computing and list its five essential characteristics
- Distinguish the three service models IaaS, PaaS and SaaS with real examples and a who-manages-what breakdown
- Compare the four deployment models public, private, hybrid and community
- Explain virtualization, how a virtual machine works, and its benefits
- Tell apart Type 1 bare-metal and Type 2 hosted hypervisors with examples
- Compare containers and Docker against virtual machines
- Distinguish elasticity from scalability, and horizontal from vertical scaling
- Compare cluster computing with grid computing
- Understand multi-tenant database architecture, cloud security threats and serverless computing
- Apply a data-centre to cloud migration strategy to a scenario