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Introduction to Cloud Computing

Issues with Traditional Data Centers

For many years, traditional IT operations infrastructure involved rapidly growing data centers with a great deal of server and operational inefficiency. Typically, physical infrastructure was required for new applications or services and single instance workloads were deployed on servers. This would result in the use of only a fraction of their available resources. This meant that many servers in a data center consumed large amounts of space and power, with low overall use.Cloud Computing

Services and applications would generally be run on local infrastructure resulting the creation of complex systems to ensure availability and backup in the event of down time or data loss. Also, in the event of new services or applications being required, the procurement and provisioning of that physical infrastructure would first need to take place thus reducing the ability of IT to react quickly to business needs.


With the introduction of virtualization technologies, data centers were able to isolate workloads and applications inside individual virtual machines. This allowed for the consolidation of these virtual machines, requiring less hardware and leading to a significant increase in resource use with reduced costs and power consumption.

The Rise of Cloud Computing

The next significant evolution for Data Center infrastructure has been cloud computing. Cloud computing builds upon virtualization to make the infrastructure much more agile and flexible. You can think of cloud computing as the pooling of not simply virtual machines but resources such as storage, networking and compute, while providing services and applications to consumers with reduced administrative or management overhead. The services can be spun up and spun down as needed.

Ultimately this provides greater elasticity for the services, efficiency and agility for the business, and accountability for the actual resource.

Organizations today are facing new realities about how they operate based on trends, which include Cloud Computing, the Consumerization of IT, the explosion of data, and the development of new social and app patterns.

What is a Cloud?

Cloud computing, or “the cloud”, has become a leading trend in IT. However, its definition is ambiguous and some of the terminology related to it is confusing. Trying to define the cloud in purely technological terms is difficult—it is best to think of it as being an abstract concept that encapsulates techniques used to provide computing services from a pool of shared resources.

Cloud solutions abstract the physical hardware and present them as virtualized resources to be used for processing, memory, storage, and networking. Many cloud solutions add further layers of abstraction to define specific services that can be provisioned and used.

The cloud can mean different things to different people depending on how they use it, whether they’re accessing email, using online software, storing files online, and so on.

On the next page, we’ll look at a scenario based on running an application in the cloud and what that involves.

Cloud Benefits Agility

Business and market opportunities can emerge and change very quickly. A viable business opportunity today may no longer be relevant tomorrow. Modern IT operations needs to be agile and able to respond quickly and easily to business changes, enabling a business to remain competitive.


Operational and Management Efficiency

Also becoming more prominent is something called Shadow IT. Shadow IT is a term that refers to Information Technology (IT) applications and infrastructure that are managed and operated without the knowledge of the organization’s IT department. Where IT is not able to respond quickly enough to meet business needs, an increasing trend has been the engaging of third party solutions by employees and departments to provide the IT requirements that will meet the need. This can result in increased risk for the business in terms of reduced control, security and compliance concerns, as well as lack of visibility. Therefore, a significant driver is the need for IT departments to position themselves as empowering businesses as opposed to being perceived as an inhibiter.

Reduced Cost

Economics are also a major driver for the cloud. In many instances it is simply much cheaper to utilize a cloud service rather than building, managing and maintaining the services yourself. This leads to a more efficient use of resources and clear and concise reporting, which helps reduce overall costs.

View the video on the next page to learn more about some of the key benefits that cloud computing provides to organizations.

Cloud Solutions: Essential Characteristics

Regardless of the specific technologies that organizations use to implement cloud computing solutions, the National Institute of Standards and Technology (NIST), the official US based standards and technology definitions body, has identified five essential characteristics that are part of a cloud computing solution.

  • On-demand self-service. The ability to allocate required resources by the end user themselves as needed without involvement from the cloud service provider.
  • Broad network access. Being accessible via standard network access mechanisms, without the need for any specialized infrastructure.
  • Resource pooling. The pooling of the various resources to be allocated from and returned to as needed.
  • Rapid elasticity. The ability to scale up and scale down as required, whether automatically or manually, without lead times being required.
  • Measured service. The ability to measure exactly what resources are being used, to monitor and control those services and to be able to present that data to the service provider or end user.

Types of Cloud Services

There are different models for cloud services depending on how a service is actually being used or provided. In terms of service types, these effectively can be broken into three categories.

Types of Cloud Services

Software as a Service (SaaS

SaaS offerings consist of fully-formed software applications that are delivered as cloud-based services. Users can subscribe to the service and use the application, normally through a web browser or by installing a client-side app. Examples of Microsoft SaaS services include Microsoft Office 365™, Skype®, and Microsoft Dynamics CRM Online. The primary advantage of SaaS services is that they enable users to easily access applications without the need to install and maintain them. Typically, users do not have to worry about issues such as updating applications and maintaining compliance because the service provider handles them.

Platform as a Service (PaaS)

PaaS offerings consist of cloud-based services that provide resources on which developers can build their own solutions. Typically, PaaS encapsulates fundamental operating system (OS) capabilities, including storage and compute, in addition to functional services for custom applications. Usually, PaaS offerings provide application programming interfaces (APIs), in addition to configuration and management user interfaces. Azure provides PaaS services that simplify the creation of solutions such as web and mobile applications. PaaS enables developers and organizations to create highly scalable custom applications without having to provision and maintain hardware and operating system resources. Examples of PaaS include Azure Websites and Azure Cloud Services, which can run a web application that your developer team creates.

IaaS offerings provide virtualized server, network and storage infrastructure components that can be easily provisioned and decommissioned as required. Typically, IaaS facilities are managed in a similar way to on-premises infrastructure, and provide an easy migration path for moving existing applications to the cloud.A key point to note is that an infrastructure service might be a single IT resource—such as a virtual server that has a default installation of Windows Server® 2012 R2 and Microsoft SQL Server® 2014—or it might be a completely preconfigured infrastructure environment for a specific application or business process. For example, a retail organization might empower departments to provision their own database servers to use as data stores for custom applications. Alternatively, the organization might define a set of virtual machine and network templates that can be provisioned as a single unit to implement a complete, preconfigured infrastructure solution for a branch or store, including all the required applications and settings.

Cloud Service Usage

You can configure and access these different service types through three different implementation models. These are Public Cloud, Private Cloud or a mixture of both using a Hybrid Cloud model. We’ll talk about each model in more detail in subsequent topics.

Cloud Service Usage

Public Cloud

Definition of a Public Cloud

A public cloud is owned by the cloud service provider (also known as a hosting provider). The cloud service provider provides cloud resources for an organization, which the end user connects to via a secure network connection, typically over the internet. The cloud vendor may share its resources with multiple organizations, or with the public. The main feature of a public cloud is that the resources that the organization uses, such as storage, processing power, various web-based applications, and other components, do not belong to the organization that is utilizing the resources, but rather to the cloud vendor. There are many cloud service providers and business can use multiple companies of varying scale.

Public Cloud Considerations

If you are a startup or have limited data, infrastructure or services to manage and maintain, the move to a cloud based service could be relatively straight forward, depending on the model and services you choose. However for companies who already have significant infrastructure moving to a cloud based model is not a trivial matter and requires a lot of upfront planning and analysis. There are also legitimate concerns about data integrity, security, management and compliance. These are real and valid concerns which end users need to satisfy themselves about before taking that step.


Pros and Cons of a Public Cloud

With public cloud services, the tenant organization has less management overhead than organizations that use private clouds. This means the renting organizations are not responsible for maintaining or supporting those resources, they just use them. However, this also means that control of the public infrastructure and services is greatly reduced because the service provider manages this for the tenant organization. In addition, the public cloud hosts the infrastructure and services for multiple organizations (multitenant), which introduces security implications that you need to review. In most cases, the cloud vendor will provide the renting organization with a service level agreement (SLA). The SLA specifies the following items:

    • What resources are being made available.
    • What failure rate or downtime is acceptable.
    • The escalation procedures if any of the resources fail.
    • The fees for different resources and services.

Private Cloud

A private cloud operates only within one organization on a private network and is highly secure. It provides cloud functionality to external customers or specific internal departments, such as Accounting or Human Resources. By creating a private cloud, you can provide a pool of resources for the infrastructure and the applications to be shared to each end user as a tenant with the respective resources that they need.

Private Cloud

When considering a private cloud implementation, an organization should evaluate carefully whether building its own private cloud is the right strategy. Depending on various factors, such as cost, availability of in-house skills, compliance, and the SLA, it may be better to outsource the hosting of the infrastructure. Business decision makers should ask themselves such questions as “what will our business look like in 3 to 5 years?” and “will our current infrastructure provide the services we need for the business to grow and survive?”

Depending on the level of control and customization you require and on the cost of implementation and management of the model, for the private cloud, there are a couple of options:

Self-Hosted Private Cloud

The self-hosted private cloud provides a dedicated on-premises environment that is internally designed, hosted, and managed.

Service Providers

Service providers will host the private cloud and make a service available to their customers. This is a dedicated environment that is internally designed but externally hosted and externally managed. It combines the benefits of controlling the service and architectural design with the benefits of outsourcing.

Hybrid Cloud

A hybrid cloud is a combination of private and public deployment models. In a hybrid cloud, specific resources are run or used in a public cloud, and others are run or used in a private cloud. A hybrid cloud offers benefits from both private and public cloud models and may be preferable when you want to control and manage some of your workloads locally but also still want to leverage some of the benefits of cost, efficiency and scale available with a public cloud model.


There are three main areas for consideration when considering hybrid cloud implementations.


One of the benefits of using a hybrid cloud is that you can seamlessly move applications and services between the private and public cloud environment. An example of this would be an in-house written web application that is currently being developed and tested in the private cloud environment. When the application is ready to go into a production environment you have the ability to move it to the public cloud. In addition you can also move a public cloud-based application to the private cloud when the need arises, such as in order to upgrade it. To accommodate this movement of resources between public and private clouds you will need to look at cross platform compatibility, i.e. what are you building or running and whether that is supported in the public cloud service.


For applications and services running in the private cloud you will typically have full control over the management and configuration of resources. For applications and services running in the public cloud however you will have less control and manageability as the public cloud vendor will take ownership of some tasks. You should be able to control and manage certain tasks such as modifying the configuration of applications, services and virtual machines but you do need to ensure you have the level of control you need.


If your organization stores sensitive customer data, such as in the payment card industry, you may prefer (or it may be a legal requirement) to keep this sensitive data in your own data centers. You may still want to offer services that are based out of a public cloud but need to have full control over sensitive data. In this scenario a hybrid cloud would suit as you can store and manage sensitive customer data in your own private cloud while offering services to your customers through a public cloud and gaining the benefits of doing so for your business.