A plum of happiness spreads over the face of an Information Technology consultant when an inquisitive customer inquires about the cloud computing. A sense of faith is bestowed upon the consultant by customer to get the right solution, and perhaps, the today's solution. In the same breath, the consultant embarks upon the difficult task of providing Information Technology solution with right platforms and Apps drawn from the mushrooming industry with a large number of cloud-based Information Technology providers, some claiming 'go cloud' to anything they offer while others having complicated proprietary solutions. Both are bad for customer, and consequently dent the credibility of the consultant.
On the other hand, the hype of cloud computing has the capability to drive the decision-making at board meetings. A single-person enterprise finds it lucrative to settle with a few cloud providers to meet their different business needs to avoid upfront investment in Information Technology. Even common people hook to the cloud for news, entertainment, education and research.
Let us consider a much cited example of travelling on an airplane. We could argue that one would prefer to purchase an aircraft, hire a pilot and crew, and also build the entire airport infrastructure to plan his or her flight schedule. Though a miniature percentage of population can still adopt this path, the general opinion will ridicule the proposition. People would rather avail similar, yet just adequate facilities, by buying a ticket with a fee from an airline. The airline company adopts a service model where the company is responsible to manage expensive assets, and to recruit and manage crew while offering services to passengers at a fee that is far below the capital investment and operation costs. Here, a passenger can avail service at a much lower cost compared to the earlier model of having a dedicated aircraft. At the same time, the airline company does profitable business by offering services to the large number of passengers. A win-win situation for both sides.
We can also discuss another popular example to bring in various important points to establish analogies with cloud computing better. This is about electricity that we consume daily at our homes, offices, and manufacturing plants.
The process of power generation, and building and maintaining its distribution network are big-scale activities in terms of both engineering and management. However, back home, we are neither concerned nor make ourselves aware of the entire supply-chain and the complexities involved in the process. We are not worried about the broader scale of operation or the costs involved. We are rather happy to use as it suites our requirements and budget; and we pay as per metered-usage.
People compare cloud computing to such service models. Well, yes it is correct up to this. Cloud computing proposes a large-scale computing system that an Information Technology vendor would establish and manage while providing all of these as services with a fee. But then, going further, it is a different service model, and it has its own unique characteristics and delivery mechanisms.
We talk of computation as a service bundle when we talk of cloud computing. We aim to use the entire platform, including server infrastructure, computer network, operating system and software applications, as a service; and aim to pay per-use basis. We pay a fee for the service, thus pay for use only.
The whole concept of 'Cloud Computing' started with using Software as a Service, or SaaS, where application service providers setup their software applications to be used on pay-per-use basis from their central infrastructures. Later, the same concept was extended to infrastructure itself, and we called it as IaaS, or Infrastructure as a Service. Similarly, we coined the term Platform as a Service, or PaaS, that referred to the availability of a software platform as a service.
This inclusive approach to computing with resources sourced from one or more vendors, located at one or more locations, and working in unison to provide highly available storage and applications, has led to the model of cloud computing. People also term this model as a technology though it can certainly be ascribed as a functional model with a bundle of intertwined technologies. Thus the use of the term as a technology in this book or elsewhere must be understood in the right spirit.
National Institute of Standards and Technology (NIST) proposed the model that can serve as a standard to understand various cloud services offered by multitude of cloud providers. The model is intended to serve as a means for broad comparisons of different cloud services and deployment methods. This also provides the basis to understand the whole paradigm, and to make the best use in business and common usages.
As per the definition by NIST, 'Cloud Computing' is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. The Cloud Model is composed of five essential characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service), three service models (cloud software as a service, cloud platform as a service, and cloud infrastructure as a service), and four deployment models (private cloud, community cloud, public cloud, and hybrid cloud).
There have been many changes in the way we do business in present times though we are oblivious of use of the technologies working behind it. Let us discuss some of the major changes that are directly related to cloud computing.
After creation, editing and sharing of online documents have been possible through cloud-based Apps, things have drastically changed the way we store data and collaborate with others. Though skeptics complain about security aspects, the ease of doing our jobs overshadowed such concerns. Currently, people collaborate at various levels using textual data, documents, audio and video; and use cloud Apps to manage their workflows with workforce spread across different geographical locations.
Cloud computing has brought Information Technology to common people due to its propositions of cost and universal access, and has attracted popular attention as it enables us to manage and use big data seamlessly. This has almost translated our discussion on general Information Technology into that on cloud computing.
In spite of significant hypes, cloud computing is not an overnight phenomenon. Rather, it has taken several years to reach its current state through complex interplay of demands by users and innovations by service providers to meet the expectations from users. Though it has received wide visibility and have started establishing itself as an inseparable way of Information Technology consumption, the evolution is still on; and more surprising impacts from this amazing computing paradigm cannot be ruled out.