A cloud is a pool of virtualized computer resources. A cloud can:
• Host a variety of different workloads, including batch-style back-end jobs and interactive, user-facing applications
• Allow workloads to be deployed and scaled-out quickly through the rapid provisioning of Virtual machines or physical machines
• Support redundant, self-recovering, highly scalable programming models that allow Workloads to recover from many unavoidable hardware/software failures
• Monitor resource use in real time to enable rebalancing of allocations when Cloud computing environments needed support grid computing by quickly providing physical and virtual Servers on which the grid applications can run. Cloud computing should not be confused with Grid computing. Grid computing involves dividing a large task into many smaller tasks that run in parallel on separate servers. Grids require many computers, typically in the thousands, and Commonly use servers, desktops, and laptops. Clouds also support no grid environments, such as a three-tier Web architecture running standard Or Web 2.0 applications. A cloud is more than a collection of computer resources because a Cloud provides a mechanism to manage those resources.
History The Cloud is a metaphor for the Internet, derived from its common
depiction in network diagrams (or more generally components which are managed by others) as a cloud outline. 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) and the term The Cloud was already in commercial use around the turn of the 21st century. Cloud computing solutions had started to appear on the market, though most of the focus at
this time was on Software as a service.
2007 saw increased activity, including 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. It was a hot topic by mid-2008
and numerous cloud computing events had been scheduled.
How does cloud computing work?
Supercomputers today are used mainly by the military, government intelligence agencies, universities and research labs, and large companies to tackle enormously complex calculations for such tasks as simulating nuclear explosions, predicting climate change, designing airplanes, and analyzing which proteins in the body are likely to bind with potential new drugs. Cloud computing aims to apply that kind of power—measured in the tens of trillions of computations per second— to
.problems like analyzing risk in financial portfolios, delivering personalized medical information, even powering immersive omputer games, in a way that users can tap through the Web. It does that by networking large groups of servers that often use low-cost consumer PC technology, with specialized
connections to spread data-processing chores across them. By contrast, the newest and most powerful desktop PCs process only about 3 billion computations a second. Let's say you're an executive at a large corporation. Your particular responsibilities include making sure that all of your employees have the right hardware and software they need to do their jobs. Buying computers for everyone isn't enough -you also have to purchase software or
software licenses to give employees the tools they require. Whenever you have a new hire, you have to buy more software or make sure your current software license allows another user. It's so stressful that you find it difficult to go to sleep on your huge pile of
money every night. installing a suite of software for each computer, you'd only have to load one application. That 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 computing system, there's a significant workload shift. Local computers no longer have to do all the heavy lifting when it comes to running applications. The network of computers that make up the cloud handles them instead. Hardware and
software demands on the user's side decrease. The only thing the user's computer needs to be able to run is the cloud computing system's interface software, which can be as simple as a Web browser, and the cloud's network takes care of the rest.
Instead of running an e-mail program on your computer, you log in to a Web e-mail account remotely. The software and storage for your account doesn't exist on your
computer --it's on the service's computer cloud.
Seven Technical Security Benefits of the Cloud
1. Centralized Data
2. Incident Response / Forensics
3. Password assurance testing (aka cracking)
5. Improve the state of security software (performance)
6. Secure builds
7. Security Testing