To understand what a cloud computing solution , then it is worth starting the “official” definition of this technology. Examine the principles of cloud computing will allow us not only to analyze in detail the nature of this technology, but also to understand in depth the benefits. The National Institute of Standards and Technology (NIST American), an ‘agency of the government dedicated to the definition of standards that can drive the progress of industry and commerce, has developed in an official document the definition of Cloud Computing universally accepted by’ industry and by industry professionals.
In this definition the cloud model is identified by five essential characteristics, three service models, and three distribution models. The essential features indicate how a cloud computing service must be structured; service models indicate what needs to provide a service cloud computing, while the distribution patterns indicate from where the services to be provided.
The characteristics of cloud computing
The five essential characteristics specify what features should be able to provide users with a cloud computing service to be defined as such:
- Self-Service : the user must be able to request the services (bandwidth, computing power, applications) independently, without the intervention of the infrastructure managers or service providers.
- Global access : the services must be accessible from multiple devices, from more places and at all times. Cloud computing needs to ensure the heterogeneous access: Mobile, tablets, small household desktop or large server.
- Pooling of resources : IT resources (storage, processors, virtual machines etc.) Must be organized in groups and not isolated so you can dynamically serve a variable number of users depending on their demands.
- Elasticity immediate : the resources must be able to climb (up and down) quickly and, in some cases, automatically.
- Measurability of services : each service has to be controlled and monitored in a transparent manner so that it can be measured in terms of resource consumption and so that we can apply the models pay per use .
Service models of Cloud computing
The models of the services, which are three, indicate what are the services that a cloud computing model must deliver:
- SaaS (Software as a Service) : in this model to be delivered as services are the software.Office 365, which lets you use online software like Word or Excel, is a SaaS model. The various Web mail services such as Gmail or Outlook.com, are examples of software services delivered via cloud computing.
- PaaS (Platform as a Service) : to be paid are the necessary infrastructure that allow you to develop, test and deploy an application. In this model we are supplied to service companies able to run applications, save the data in a database or in a file store, process information, and so on. Windows Azure Microsoft, with which you can deploy applications written with .Net platform and other programming languages, or the Google Cloud Platform is a PaaS model.
- IaaS (Infrastructure as a Service) : in this model to be provided is the entire IT infrastructure.The customer can buy, from a virtualized environment, computing power, entire machines, space, network services in order to deliver autonomously your services or your own applications.
The distribution patterns of Cloud computing
If the characteristics indicated as must be a service of Cloud computing and service models indicated the thing , the distribution patterns instead indicate where a cloud computing model has to be organized. In this case the possible alternatives are four.
- Private Cloud : The Cloud computing services are provided by the company, or by an external provider, only the company itself and its various units ( on-premise ). What matters is the fruition of the services: the infrastructure can be managed or operated by the company itself or by an external provider, the property can be internal or external, but the services must be the prerogative of a single organization.
- Community Cloud : The Cloud computing services are provided by a company or a service provider to a select group of organizations that share some features like, for example, security levels, legal requirements, objectives and so on. Also in this case the infrastructure can be handled or operated by one of the companies of the group or by an external provider.
- Public Cloud : Cloud computing services are provided through the Internet from a different service provider customers. The infrastructure, platform, applications are owned by the service provider, are managed by the service providers and are shared with more customers.
- Hybrid Cloud : the services are built on hybrid infrastructure that use the private mode for some aspects (for example the retention of data) and the public mode for other (for example the access interfaces).
From this description it is clear that cloud computing is not just a technology, but a big architectural revolution involving all levels of IT: the software we use every day to read e-mail, to servers that distribute our application, the configuration of the entire IT infrastructure.In all these areas the cloud technologies are able to improve existing technologies, lower acquisition costs, improve the efficiency of services, to enable innovative processes. And it is a transformation that affects not only large or very large companies, but anyone using computer tools.
To understand how they fit into the different combinations of cloud to the various areas of our businesses, and leaving aside for this series of articles the so-called personal cloud, ie the Cloud dedicated to individuals, we see some examples of possible use of the Cloud for different types of organizations.
A new startup of professionals: SaaS in the Public Cloud
A startup needs to address in a short time high costs for structuring its own IT services: e-mail services, productivity software, communications services and internal collaboration. The levels of flexibility of IT tools should be very high, as is the company’s dynamism: the services must be accessible from different devices, shared documents between all the employees, the organization of work must be able to be managed from different locations and at all times.Traditional infrastructure in this case would be expensive to design and put into production (purchase of computers, purchase of servers, services configuration), it is difficult to manage and maintain. Not to mention that some features, such as the use of the Internet for sharing and collaboration, would objectively very difficult to setup with levels of quality and adequate security. Acquiring software services (SaaS) distributed by a Public Cloud instead allows, on the one hand, to save the acquisition costs and can, over time, add or delete service quotas to tailor the solution to the size, the other of you can get a high quality of services without having to worry about maintenance and management, which takes place in the datacenter of the service provider with costs included in your subscription.
A software: PaaS in Public Cloud
The software companies are firms that, on the front line and in direct contact with the consumer, addressing the main effects of the information revolution made of new apps, social connections, on-demand services. Users are increasingly demanding and expect even the specific applications they use at work, efficiency, usability and interoperability. The modern workstyle, the work order imposed by the use of smartphones and web services, has become a necessity for companies, both also for developers who must provide them with the business software. Even in this case, on scalable services and interconnected internally it is expensive and inefficient. Relying on a provider of programming platforms (PaaS) distributed on a public cloud can receive services to distribute your application through the Internet will have access to scalable infrastructure, always connected, integrated with the most popular services (mobile notifications, multimedia streaming) and the very high quality of service.
An SME: SaaS and IaaS in Cloud Hybrid
Even companies with well-established IT infrastructure and major accomplishments in technology will have to deal with pay Cloud. First or later any company you are in the position of having to renew its architecture because it obsolete, no longer supported or no longer sufficient to follow the company’s activities. Any company will therefore in a position to choose whether to completely renew its architecture, purchasing new hardware to accommodate new software, or if you begin to move in the Cloud services that you intend to renew, keeping others on the infrastructure you already own. It is a solution Cloud Hybrid which preserves existing investments and, above all, to gradually test the utility of the new model, to assess the advantages and disadvantages of Cloud, beginning to test the effectiveness of the solution and addressing the new investment with tranquility.
A large company: IaaS and SaaS in Private Cloud
The typical condition of large enterprises datacenter, is that of a disorganized growth over time. In most of these scenarios we are facing an infrastructure grew year after year with different operating systems installed on different servers supported storage systems and network also different from each other. A data center like that, difficult to operate and manage, is a bottleneck for the company, with IT that will always be one step behind its demands. In this case a solution Private Cloud allows, on the one hand, to consolidate the virtualization tools through the entire hardware infrastructure, whether it be storage, server, or network, and on the other to introduce, above this level consistent virtualized , a series of monitoring and automation services that facilitate maintenance and management, enabling the principles of cloud computing and enable iT to regain the agility needed to run the enterprise.