'Behind the cloud seven, all wishes and dreams are fulfilled according to the faith of the people in ancient times. Now, IT professionals and analysts have rediscovered the cloud.' 1)
Cloud computing is the latest technology trend and a new paradigm for the use of IT. According to Gartner 2), “Cloud Computing will be as influencial as E-business” at its time of arrival. Cloud Computing mainly refers to the provision of IT resources by a provider via the Internet (fix and mobile). It is often also perceived as a derivative of ASP (Application Service Providing) and Software as a Service (SaaS), yet there are significant differences in its deployment and application. Due to its ease of application and lack of complexity, Cloud Computing Services are usually deployed within an SME environment.
Users can access these resources, which are typically based on a shared infrastructure and are “ready made” applications, with a standard browser (Firefox, Internet Explorer, Google Crome, Opera a.o.). Besides the access simplicity, Cloud Computing unlike business software packages such as SAP, Oracle etc. usually does not require a significant up-front investment. Finally, it does require neither the build up of extensive know-how nor of additional resources to integrate the application into an existing IT infrastructure (personnel, HW, SW).
There are three kinds of cloud computing: Public Cloud, Private Cloud and Hybrid Cloud
This cloud is “open” for everyone. Users can access their data comfortably no matter where they are, as long as they have an Internet connection. A well-known Public Cloud system is an e-mail system like GMail or GMX FreeMail.
Only select users have access to the cloud. Therefore, security standards are higher than in public clouds. Often this kind of cloud is used in large companies as Deutsche Telekom. For instance, the employees of the company need a smart card to identify themselves, but then have access to companies data bases - no matter where they are.
This cloud is a combination of both public and private cloud. Some security items are active, but they are customized to lower security needs. So providing of a hybrid cloud is cheaper than providing a private cloud due to the lower security efforts, but with access to a limited number of user in contrast to a public cloud
In addition to such a simple handling (“ease of use”), cloud computing services payment is based on a subscription fee per user-licence and on-demand - per usage and per feature requested (if authorized). This payment model is called “Pay-as-you-use” 3) model, which has been established as a de facto industry standard payment model.
Cloud Computing offers can span the entire IT portfolio, including hardware (i.e. CPU usage, storage, archiving and backup solutions), software (i.e. applications such as CRM, e-mail system or Web-conferencing) or services such as spam filtering.
Due to the nature of a shared infrastructure, applications and web-based access to these resources, security in access, data handling/processing (server) and web-based exchange (internet) becomes a critical issue and a key-element of all Cloud Computing offers. Therefore often all three elements of this communication chain are secured: Servers via certificates and a dedicated firewall, web-based exchange via SSL encryption and the browser based access via a dedicated client. Yet, usability requirements will allow for a registered user to securely access the service, providing user name and password.
There are global Cloud Computing service providers, while there are also specialized local enterprises offering customized support and add value through consulting services. Besides these global Web-players, IT-giants such as HP, Dell and IBM are developing their cloud services, spanning from SaaS to IaaS (Infrastructure as a Service), PaaS (Platform as a Service) to CaaS (Communication as a Service). In addition, telecommunication service providers are entering the competition and add value by bundling their secured access services (fix & mobile) in order to provide the customer with an individual offer and compete with global players.
— Udo Lorenz 2011/04/20 21:17