3. WORKING OF CLOUD COMPUTING
4. CLOUD ARCHITECTURE
6. TYPES OF CLOUD COMPUTING
7. ROLES PLAYED IN CLOUD COMPUTING
6. CLOUD SERVICES
8. ADVANTAGES AND DRAWBACKS
Cloud computing is Internet ("cloud") based on development and use of computer technology ("computing").It is a style of computing in which dynamically scalable and often virtualised resources are provided as a service over the internet.Users need not have knowledge of, expertise in, or control over the technology infrastructure "in the cloud" that supports them. The concept incorporates infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS) as well as Web 2.0 and other recent (ca. 2007-2009) technology trends which have the common theme of reliance on the Internet for satisfying the computing needs of the users. Examples of SaaS vendors include Salesforce.com and Google Apps which provide common business applications online that are accessed from a web browser, while the software and data are stored on the servers.A cloud is a pool of virtualized computer resources. A cloud can: 1.Host a variety of different workloads, including batch-style back-end jobs and interactive, user- facing applications. 2.Allow workloads to be deployed and scaled-out quickly through the rapid provisioning of virtual machines or physical machines. 3.Support redundant, self-recovering,highly scalable programming models that allow workloads to recover from many unavoidable hardware/software failures. 4.Monitor resource use in real time to enable rebalancing of allocations when needed.
Fig 1.1: Overview of cloud computing
The underlying concept dates back to 1960 when John McCarthy opined that "computation may someday be organized as a public utility"; indeed it shares characteristics with service bureaus which date back to the 1960s.The term cloud had already come into commercial use in the early 1990s to refer to large ATM networks.By the turn of the 21st century,the term "cloud computing" had started to appear, although most of the focus at this time was on Software as a service (SaaS). In 1999, Salesforce.com was established by Marc Benioff, Parker Harris,and his fellows.They applied many technologies of consumer web sites like Google and Yahoo! to business applications. IBM extended these concepts in 2001,as detailed in the Autonomic Computing Manifesto-which described advanced automation techniques such as self-monitoring, self-healing, self-configuring, and self-optimizing in the management of complex IT systems with heterogeneous storage, servers, applications, networks, security mechanisms, and other system elements that can be virtualized across an enterprise. Amazon.com played a key role in the development of cloud computing by modernizing their data centres after the dot-com bubble and, having found that the new cloud architecture resulted in significant internal efficiency improvements,providing access to their systems by way of Amazon Web Services in 2002 on a utility computing basis. 2007 saw increased activity,with Google,IBM and a number of universities embarking on a large scale cloud computing research project, around the time the term started gaining popularity in the mainstream press.
WORKING OF CLOUD COMPUTING
Fig 1.2: Working of cloud computing
In cloud computing you only need to load one application.This application would allow workers to log into a Web-based service which hosts all the programs the user would need for his or her job. Remote machines owned by another company would run everything from e-mail to word processing to complex data analysis programs.It's called cloud computing, and it could change the entire computer industry.
In a cloud...