Cloud is a broad concept often liberally over-used, misused and abused, covering virtually every possible type of online service, so an official definition is warranted.
The National Institute of Standards and Technology (NIST) defines Cloud Computing as... “A model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction" (NIST, SP-800-145).
It is described as comprising these five (5) essential “must-have” characteristics:
Broad Network Access: The system must be accessible everywhere on various devices - mobile devices, laptops, workstations, etc.
Rapid Elasticity: Compute, Storage and Network resources may be dynamically provisioned and released, to scale rapidly outward and inward commensurate with demand.
On Demand Self Service: The system must feature a self-service catalog of offerings available to users who must be able to unilaterally provision resources as needed and automatically without human interaction from IT service providers.
Resource Pooling: The system must be able to service multiple customers from the same physical resources, by securely separating the resources at the logical level.
Measured Services: The system must provide accountability by way of a show-back / charge-back mechanism that keeps track of which users are employing which resources, how much and for how long.
Cloud can be leveraged according to any or all of the following Deployment models - Public, Private and Hybrid Cloud, described in Figure 1.
Lastly, Cloud is delivered via one of the three core services delivery models - Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Service (SaaS), each with its own advantages, disadvantages, intricacies and shared responsibility model as described in Figure 2.
Infrastructure as a Service (IaaS)
The infrastructure layer builds on a hypervisor / virtualization layer by offering the virtual machines as a service to users. Instead of purchasing servers or even hosted services, IaaS customers can create and remove virtual machines and network them together at will. Clients are billed for infrastructure services based on what resources are consumed. This eliminates the need to procure and operate physical servers, data storage systems, or networking resources.
Platform as a Service (PaaS)
The platform layer rests on the infrastructure layer’s virtual machines. At this layer customers do not manage their virtual machines, they merely create applications within an existing API or programming language. There is no need to manage an operating system, let alone the underlying hardware and virtualization layers. Clients merely create their own programs which are hosted by the platform services they are paying for.
Software as a Service (SaaS)
Services at the software level consist of complete applications that do not require development. Such applications can be email, customer relationship management, and other office productivity applications. Enterprise services can be billed monthly or by usage, while software as service offered directly to consumers, such as email, is often provided for free.
Cloud is undoubtedly a game changer but it is no easy undertaking and should not be entered into lightly, with reckless abandon or with overbearing frugality. The great news is, you don’t have to go it alone. By partnering with an experienced vendor, such as BreezeIT with over 30 years of industry expertise, your transition to the Cloud can be a success, delivered securely, on-time and on-budget. Contact BreezeIT today and learn how our portfolio of Cloud Services can help you achieve mission success.
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