Aug 19, 2014

The term “cloud computing” covers a wide range of concepts, technologies, and techniques for creating scalable, flexible, and manageable IT infrastructure solutions. Today, I’ll explain the concept of cloud computing, cloud services, types of cloud and the Microsoft cloud technologies available. What is cloud computing? Cloud computing, or “the cloud,” has become a leading trend in IT. However, its definition is ambiguous and some of the terminology related to the cloud is confusing. It is difficult to define the cloud in purely technological terms, and it is best to think of the cloud as being an abstract concept that encapsulates techniques used to provide computing services from a pool of shared resources. Most cloud solutions are built on virtualisation technology, which abstracts physical hardware as a layer of virtualised resources for processing, memory, storage, and networking. Many cloud solutions add further layers of abstraction to define specific services that can be provisioned and used. Regardless of the specific technology used to implement it, the National Institute of Science and Technology have identified that cloud computing solutions exhibit the following five characteristics:

1. On-demand self-service: Cloud services are generally provisioned as they are required, and require minimal infrastructure configuration by the consumer.
2. Broad network access: Cloud services are generally accessed over a network connection – either a corporate network or the Internet.
3. Resource pooling: Cloud services use a pool of hardware resources that are shared across consumers.
4. Rapid elasticity: Cloud services scale dynamically to obtain additional resources from the pool as workloads intensify, and release resources automatically when they are no longer needed.
5. Measured service: Cloud services generally include some sort of “metering” capability that makes it possible to track relative resource usage by subscribers.

Cloud services Cloud services generally fall into one of the following three categories:

1. Software as a Service (SaaS) SaaS offerings consist of fully-formed software applications that are delivered as a cloud-based service. Users can subscribe to the service and use the application, usually through a web browser or by installing a client-side app. Examples of SaaS offerings include Microsoft Office 365, Skype, and Microsoft Dynamics CRM Online. The primary advantage of SaaS offerings is that users can easily access an application without the requirement to install and maintain it, and benefit from automatic updates to the application.
2. 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 offerings encapsulate fundamental operating system (OS) capabilities, including storage and compute, as well as functional services for custom applications. Usually, PaaS offerings provide application programming interfaces (APIs), as well as configuration and management user interfaces. Microsoft Azure provides PaaS services that simplify the creation of web applications, mobile applications, and other solutions. PaaS offerings enable developers and organisations to create highly scalable custom applications without having to provision and maintain hardware and operating system resources.
3. Infrastructure as a Service (IaaS) IaaS offerings provide virtualised server and network infrastructure components that can be easily provisioned and decommissioned as required. IaaS services are typically managed in a similar way to onpremises 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 with a default installation of Windows Server 2012 R2and SQL Server 2014, or it might be a completely pre-configured infrastructure environment for a specific application or business process. For example, a retail organisation might empower departments to provision their own database servers to use as data stores for custom applications, or it might define a set of virtual machine and network templates that can be provisioned as a single unit to implement a complete infrastructure solution for a branch or store, including all of required applications and configuration. Types of cloud Cloud services can be provided in a public cloud, a private cloud, or in a combined hybrid cloud environment. Public cloud services are hosted in external data centers that are managed by a cloud provider. In some cases you can consume public cloud services directly from the cloud provider, while in other cases the cloud services may be accessed through a third-party Internet service provider. In either case, the services are hosted on servers that are external to your organisation, and usually you share the data center with other customers in a multi-tenant solution (though typically a degree of isolation is provided to ensure security and confidentiality). In most public cloud solutions, you subscribe to one or more services and pay only for what you use. Private cloud services are hosted on an organisation’s own infrastructure, which is abstracted using virtualisation. The IT department of the organisation manages the data center as a shared pool of server and network resources that can be used for applications and business processes on an on-demand basis. Business units and individuals in the organisation can provision and consume services in the private cloud in a similar way to public cloud services. In many organisations, some services are provided through a public cloud platform while others are managed in a private cloud. These organisations often need to integrate their public and private cloud platforms to provide a single, consistent experience for users in which the actual location of the services being consumed is not a factor for users to consider. Hybrid cloud solutions enable organisations to migrate IT infrastructure to public cloud services at their own pace, and retain full control of IT resources for applications and data that contain sensitive data or have restrictive compliance requirements. Hybrid cloud environments also enable infrastructure and application architectures that take advantage of public cloud solutions for backup and high availability of on-premises applications. Microsoft cloud technologies Microsoft has invested heavily in building a cloud platform for individual consumers and enterprises. Most, if not all, Microsoft products provide or consume cloud-based services in one way or another. The following list describes some of the key Microsoft technologies that can be used to build enterprise cloud solutions.

• Office 365 is a SaaS version of Microsoft Office. Enterprises can purchase Office 365 subscriptions that include productivity applications such as Microsoft Word and Microsoft Excel, and online services including a hosted SharePoint Server and browser-based Office web applications.
• Microsoft Azure is a complete cloud platform that offers PaaS and IaaS services. Enterprises can build their own applications on Windows Azure services, and they can provision and manage virtual machines that are hosted in Microsoft Azure data centers.
• Hyper-V is Microsoft’s virtualisation technology, and it provides the foundation for Microsoft’s public and private cloud platform. Microsoft Azure is based on Hyper-V, and enterprises can use the same virtualisation capabilities to host their own private cloud services.
• Windows Server 2012 R2 is the evolution of Windows Server and includes scalability, security, and resource management features that make it ideal for cloud scenarios. Windows Server 2012 R2 can be used as both a Hyper-V host and as a guest OS.
• System Center 2012 R2 is a suite of products that enable enterprises to provision and manage private and public cloud services, consistently and effectively.
• The Microsoft Azure Pack builds on Windows Server 2012 R2 and System Center 2012 R2 to provide Microsoft Azure PaaS services in a private cloud. The consistent portal interface makes the provisioning and management of cloud services consistent, whether using the Microsoft Azure public cloud or a Windows Server and System Center based private cloud.

So with all of that information, you should have a general gist of what there is to know about the cloud. In my next post, I’ll specifically look at Microsoft Azure, its app services, data services, services to support networking, data storage and more.