The Cloud
Do you remember how we described virtualization at the beginning of this course as the fundamental technology that powers “cloud computing”, and how we said that cloud computing delivers computing resources, software, or data as a service over the internet? What does that look like in everyday life for individuals, and why is “the cloud” so important for organizations and businesses?
You’ve probably been using “the cloud” for a long time without realizing it! Have you ever used a search engine (such as Yahoo), or streamed a movie (maybe on Netflix), or used web-based email (such as Outlook), or shared a document online (using something like Google Docs)? All of these are provided through “cloud computing”, which is simply on-demand delivery of computing services over the internet. This very course is being brought to you via the cloud!
For businesses and organizations, cloud computing gives users, developers, and IT administrators access to shared applications, systems, and storage maintained by someone else – wherever and whenever they need it. And it does so at the speeds that are needed in our increasingly “connected” world.
It is important to note that a cloud is typically made up of one or more data centers. A company that provides public cloud services will probably have many data centers in order to maximize its return on investment, revenue, uptime, redundancy, and efficiency, and to achieve its business goals.
Did You Know?
Businesses running systems and applications on the cloud can potentially reduce their per-user carbon footprint by 30 percent for large companies and 90 percent for small businesses.
Source: http://iasir.net/AIJRHASSpapers/AIJRHASS15-175.pdf
Why do organizations and businesses use virtualization for cloud computing? Because using virtualization increases the efficient use of hardware, which in turn lowers the cost of building, sustaining, and hosting computers in data centers as a cloud service. Virtualization products are therefore extremely important to businesses operating private or public clouds.
How does an organization or business transfer the operations of its physical data center to the cloud? It’s a step-by-step process, beginning with virtualizing the servers. At the end of the process, the result will be even more agility and increased self-service.
Types of Cloud Computing
The use of cloud computing is expanding at an incredible pace. This is great for businesses and organizations as they now have more and more options about how to achieve their IT goals. To help them decide how to achieve those goals best, cloud computing is categorized into different types or “service models”. The three major types are Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS).
Of these three types, Software as a Service is the simplest to use and the easiest to deploy. With SaaS, users have direct, on-demand access to shared applications and data over the internet. There’s no software to install or configure – everything is available via a web browser. Microsoft’s Office 365 and Slack are two popular and widely-used SaaS products.
For users who need more control and flexibility, there’s Platform as a Service. With this service model, web developers and programmers can upload their content to pre-configured web servers, database servers, and application servers without having to install or maintain any of the servers’ applications or operating systems. Amazon Simple Storage (a.k.a. Amazon S3), Amazon Route 53 Amazon Web Services, and Google Cloud are widely-used PaaS providers you may have heard of. Amazon S3 offers “object storage” (that’s data stored as objects rather than as file systems or as blocks) via a web interface. Amazon Route 53 is a domain name system (DNS) which means that it translates website names (e.g., www.cloudstudent.com) into numeric IP addresses (e.g., 123.4.5.6). These PaaS offerings all have one thing in common, and that is that they are ready-to-go services that don’t require the need to build or install anything from scratch. What differentiates this from a SaaS environment is that you have the extra ability to build on top of the services by, for example, using application program interfaces (APIs) to integrate with another service and life-cycle management.
Did You Know?
Cloud providers are taking the initiative by committing to goals for sustainable computing. For example, VMware will partner with major cloud providers (AWS, Azure, Google, etc.) to help customers transition to using zero-carbon public cloud resources. In addition, through its VMware Cloud Provider Program, which offers software-as-a-service through a global network of partner cloud providers, VMware is planning on working with partners to increase the availability of zero-carbon clouds.
For maximum control, Infrastructure as a Service gives you access to a dedicated virtual or physical system that you manage and maintain yourself. IaaS provides the greatest degree of flexibility and customization of the three cloud computing types. Though Amazon Web Services was mentioned earlier as a popular PaaS provider, they are more famously known as an IaaS provider which highlights the flexibility that providers may have. Digital Ocean is also another widely known IaaS provider.
Imagine that the individual components of your IT infrastructure are the ingredients of an apple pie. So instead of apples, sugar, flour, butter, cinnamon, salt, nutmeg, and lemon juice, think applications, data, storage, operating systems, virtualization, servers, storage, and networking!
Now imagine that you want to make the ‘pie’ yourself: you have all the ‘ingredients’, and want to use and manage them yourself. This would be the equivalent of having all your IT infrastructure on-premises, with you having sole responsibility for them:
What if you only wanted to be responsible for the applications, data, operating system, and software ‘ingredients’, but not for the others? Another company would have to manage your virtualization, storage, servers, and networking. This would be Infrastructure as a Service:
You could choose to manage just your applications and data and have another company be responsible for your operating systems, software, virtualization, storage, servers, and networking. This would be Platform as a Service:
If you didn’t want any responsibility whatsoever, you’d go for Software as a Service, and another company would manage everything - applications, data, operating systems, software, virtualization, storage, servers, and networking:
These three service models are sometimes collectively known as the “cloud computing stack” as they build on top of one another, with IaaS at the base, PaaS in the middle, and SaaS at the top.