Four firms, four problems
Four firms all say "we are moving to the cloud". But they mean different things.
A bakery wants email and documents with no servers to look after. A game studio wants a blank powerful computer it can switch on for a week. A web agency wants to run its code and never touch the operating system (the main software that runs a computer). A school wants somewhere cheap to keep ten years of photos.
Each one needs a different kind of cloud service.
Key words
| Word | What it means |
|---|---|
| Cloud computing | renting computing power, programs or storage over the internet |
| IaaS | infrastructure as a service: you rent a computer, storage and network, and look after the rest yourself |
| PaaS | platform as a service: you rent a ready place to run your own program |
| SaaS | software as a service: you rent a finished program and use it in a browser |
| Cloud storage | disk space you rent over the internet, paid for by the amount you use |
| Operating system | the main software that runs a computer |
| Virtual machine | a computer made of software that runs inside a real one |
| Personal data | facts about a living person who can be named from them |
| Database | an organised store of data that programs can search |
| Provider | the company that runs the cloud and rents it to you |
| Network | computers and devices joined together so they can share data |
| Scalability | being able to add more power when more people use the system |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can choose between IaaS, PaaS, SaaS and cloud storage for a job, and say who looks after each layer.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Three levels of renting
IaaS gives you the basics: a virtual machine, storage and a network. You choose the operating system, install your programs and keep them updated. You get the most control and the most work.
PaaS gives you a ready place to run your code. The provider looks after the operating system and updates. You only bring your program and data.
SaaS is a finished program, such as email or a spreadsheet in a browser. You just log in and use it.
Who looks after each layer
| Layer | On your own site | IaaS | PaaS | SaaS |
|---|---|---|---|---|
| Building and hardware | You | Provider | Provider | Provider |
| Network and storage | You | Provider | Provider | Provider |
| Operating system | You | You | Provider | Provider |
| Runtime and tools | You | You | Provider | Provider |
| Your program | You | You | You | Provider |
| Your data and users | You | You | You | You |
The cells students fill in are left blank in this preview.
Quick check
Have a go
Quick check
4 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.