Cloud computing refers to both the applications delivered as services over the Internet and the hardware and software systems in data centers that provide these services. Hardware and software data center is what we call a cloud. Cloud computing is a relatively new concept and it has become popular recently. Recent leverage virtualization technologies and cloud computing will be a logical separation between different nodes, each node appears as a different physical machine to the user. Unlike the grid, makes several distributed computers linked together to form a logical computer that can handle a large amount of data and computation. In the case of Cloud Computing virtualization technology that allows each node to appear as a separate physical machine that allows the user to load custom software and operating system on each node and configure custom rules for each node.
The idea of cloud computing has evolved from parallel processing, distributed computing and grid. There is significant similarity between them, but they work differently. Although cloud computing is an emerging field of computer science, the idea has been around for several years. It's called cloud computing because data and programs are the "cloud" of web servers. To simplify the concept, cloud computing can be defined simply as the sharing and use of applications and resources in a network environment to get the job done without worrying about the ownership and management of network resources and applications. According to the scale, with cloud computing, computing resources to obtain work and their information is not stored on the PC, but the host is available elsewhere at any place and at any time.
Second Related Technology Comparison
2.1. Grid form of distributed computing and parallel computing, whereby a 'super and virtual computer consisting of a cluster of networked, loosely-coupled computers that work together to perform major tasks
2.2. Utility computing packaging of computing resources, such as computing and storage, as measured by a similar traditional public services such as electricity.
2.3. The autonomic computing
Computer systems that can self-government.
Third General mechanism
Cloud computing using information technology as a service over the network. The concept includes general infrastructure as a service (IaaS), Platform as a Service (PaaS), Hardware as a Service (Haas) and Software as a Service (SaaS). This may be the ability to rent a server or servers and run the application of geophysical modeling available anywhere. This may be the ability of (S Rupley, 2009) to rent a virtual server, load the software on it to turn it on and off at will, or cloned to meet the sudden demands of the task. It can be guarding and securing large amounts of data that is accessible only by authorized applications and users. This can be supported by the cloud provider that sets a platform with the ability to scale automatically in response to load changes. It can be used to keep the cloud storage applications, business and personal information. And this may be the possibility of using a handful of Web services to integrate photos, maps and GPS information to create a cover customers in web browsers.
In the cloud computing system, there is a significant change of job. The local computer does not have to run the application. Network of computers that make up the cloud handles them instead. In this situation, buying hardware and software on the user side is reduced. Let the cloud take care of it. The only thing that the local computer must be aware of the interface software that will run the program. Today, as the web browser Mozilla Firefox and Internet Explorer 8 is widely used as the interface software in the cloud computing system.
The truth is, Internet users already use some form of cloud computing. If you have an e-mail with a Webbased email service such as Hotmail, Yahoo! Mail or Gmail, then you have had some experience with cloud computing. Instead of running an e-mail program on the local computer, users will log into the web account email remotely. Software and storage for the account does not exist in the local computer is the computer service cloud.
4th The key feature of Cloud Computing
Currently, there is no standard definition or specification of Cloud Computing. On May take some time to define the key features of Cloud Computing on the basis of practice in field.Based to practice in the area of services and solutions for the design award, the following two key enabling technologies could play an important role in the revolutionary phase of cloud computing:
4.1. Virtualization Technology
Virtualization technologies for handling files that the operating system, middleware and applications proliferate and assigned to a physical computer or a stack of servers away. Virtualization Technology also can help re-license the operating system, middleware, or software application, a subscriber is relieved of his services cloud computing platform.
4.2. Service-oriented architecture (SOA).
Service-oriented architecture is essentially a set of services. These services communicate with each other. The communication can involve either simple data passing by, or may include two or more services coordinating some activity. Some means of connecting services to each other is necessary. Development of a system or software architecture is now moving towards a services-oriented, unlike a few decades most of the program is a standalone and intentionally disposable. Recently, the tremendous growth of Internet users and Internet access technology, the software can now rent. Giant companies such as Google, Microsoft, Sun or even Amazon have this ability to provide software services instead of selling the software directly to customers. SOA is a software or system architecture to deal with componentization, reusability, extensibility and flexibility. This feature is based around the need for companies that are looking to cut costs and opt to rent instead of buying.
