Cloud Basics

What is cloud?

A cloud service is a resource that is provided over the Internet. The service can be for example a software, database or computer. Cloud can be either public or private.

Public cloud

In a public cloud services and infrastructure are provided off-site over the internet. A public cloud is good choice when

  • you need to test and develop application code
  • you need ability to add computer capacity for peak times

The biggest public cloud service providers are Amazon, Microsoft and Google.

Private cloud

In a private cloud services and infrastructure are maintained in a private network. These clouds offer the greatest level of security and control, but they require the company to purchase and maintain all the software and infrastructure. A private cloud is good choice when

  • company is part of an industry that must conform to strict security and private issues
  • company is large enough to run cloud data center efficiently and effectively on its on

Hybrid cloud

In a hybrid cloud companies can maintain control of an internally managed private cloud while relying on the public cloud when needed. For instance during peak periods applications can be migrated to the public cloud.

Why to public cloud?

#1 It’s effortless

Well it can be. You can setup new web app in minutes. But setting up more complex virtual network, virtual machines and security policy will take time. Also some of the clouds are easier to setup than others.

#2 It’s scalable and reliable

System scales automatically when needed. Servers and other resources can be added or removed within a few minutes delay.

#3 It’s cost effective

A company pays only for the resources they are using. The service is billed on a monthly and hourly basis.

When to cloud?

  • When a company needs to deploy new web or mobile application
  • When a company needs test environment for new operating system or application versions
  • When a company needs to renew servers and operating systems
  • When a company is building a new IT network
  • When a company needs backup service

Cloud Service Providers


Amazon Web Services (AWS) is the oldest and biggest cloud service provider. It was launched already 2006 and nowadays it operates from 12 geographical regions across the world. AWS has now over 70 services including compute, storage, networking, database, analytics, application services and tools for IoT.


Google Cloud Platform provides developer products to build and deploy programs from simple websites to complex applications. Google’s own consumer products like Google Search and YouTube are running on Google Cloud Platform.


Heroku is a cloud Platform as a Service (PaaS). It was found on 2007. So it is one of the oldest cloud services. Currently it supports several programming languages including Ruby, Java, Python and Node.js. Heroku runs on Amazon Web Services.


Microsoft Azure is cloud computing platform (PaaS) and infrastructure (IaaS) for building, deploying, and managing applications and services through a global network of Microsoft managed data centres. Microsoft Azure was released in 2010.


There are thousands cloud service providers all over the world. Some of them provide only one thing, like database as a service, platform as a service or just virtual machine. Biggest service providers support both PaaS and IaaS, which makes them more complicated. For example creating a database to a mLab is much easier / faster than creating a database to Microsoft Azure even same service works in both places.

Biggest cloud customers are also biggest cloud service providers. All the biggest cloud service providers have their own consumer cloud applications. Microsoft has Skype, Office 365 and so on. Google has Gmail, Google Docs. Amazon has its web stores. Facebook has own data centres where it provides their own services.

Cloud Service types

The most common cloud service types are Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as Service (IaaS).

Software as a Service (SaaS)

SaaS is a software distribution model in which third-party provider hosts applications and makes them available to customers over the internet. Usually services are billed monthly basis. SaaS examples: Gmail, Facebook, Dropbox. User group: consumers.

Platform as a Service (PaaS)

Platform as a Service remove the need to manage the infrastructure (hardware and operating systems). Users can focus on application deployment and management. Users don’t need to worry about capacity planning or software maintenance. PaaS service providers are: Google App Engine, Heroku, Microsoft Azure and Amazon Web Services. User group: application developers.

Infrastructure as a Service (IaaS)

IaaS is a self-service model where users are responsible for managing applications, data and operating systems. Service provider manages servers, hard drives, storage and networking.  Amazon Web Services is one of the biggest and oldest IaaS service providers. Other providers are Microsoft, Google and IBM. User group: IT architects.