It is a style of computing where massively scalable IT-related capabilities are provided to users as a subscription-based or pay-per-use service that is accessible in real time over the Internet to multiple external customers. It can extend the existing capabilities of an IT department and provide significant economies of scale. Most organizations that are currently accessing the cloud are using it to supplement their existing IT capabilities. In time, they may choose to move all of the computing needs to the cloud.
Some examples of cloud related services include:
Software as a service (“SaaS”) is a software delivery model where a software vendor develops a Web-native software application and hosts and operates the application for use by its customers over the Internet. The customer does not own the application, which can be accessed by multiple customers simultaneously, but generally pays for using it. Salesforce.com, Inc. (CRM (LAST: 158.13 7/8/2011 9:15:01 AM) (LAST: 158.13 7/8/2011 9:15:01 AM) ) is the poster child for the SaaS vendors. Other companies include Netsuite (N (LAST: 0 12:00:00 AM) (LAST: 0 12:00:00 AM) ), Salary.com (SLRY (LAST: 4.09 12/31/1969 7:00:00 PM) (LAST: 4.09 12/31/1969 7:00:00 PM) ), Constant Contact (CTCT (LAST: 25.25 12/31/1969 7:00:00 PM) (LAST: 25.25 12/31/1969 7:00:00 PM) ), Taleo (TLEO (LAST: 36.79 12/31/1969 7:00:00 PM) (LAST: 36.79 12/31/1969 7:00:00 PM) ) and DemandTec (DMAN (LAST: 7.81 12/31/1969 7:00:00 PM) (LAST: 7.81 12/31/1969 7:00:00 PM) ).
Data as a Service is focused on delivering data in response to a query rather than providing access to a more elaborate, full-blown application. Google search falls into this category.
Utility computing, also referred to Hardware as a Service, allows customers to rent storage space and servers as they need them. The participants in this space include Amazon's Elastic Compute Cloud (EC2), Salesforce.com's AppExchange, IBM’s Deep Computing Capacity on Demand, Google’s App Engine, Rackspace’s Cloud FS, and Dell’s Cloud Computing Solutions.
Platform as a service provides programmers and companies with a development environment to build applications that run on the provider's infrastructure and are delivered to users from the provider's servers.
Managed service providers (“MSP”). Managed service providers offer fully outsourced network management services that include advanced features like IP telephony, messaging and call center, virtual private network, managed firewalls, and the monitoring of network servers.
The Top 100 Bloggers of Cloud Computing: