Explanation: What is cloud computing?

Three types of cloud computing

Source: http://www.pilicat.com

1,IAAs(Infrastructure as a service, infrastructure as a service) provides data centers, infrastructure hardware, and software resources over the Internet. IAAs provides servers, operating systems, disk storage, databases, and/or information resources. The most advanced IAAs products are Amazon's AWS (Elastic Compute Cloud), but IBM, VMWare, HP, and other traditional IT vendors also provide such services. IAAs usually introduces other usage and pricing models according to the "elastic cloud" model, that is, they only use the services you need at any specific time, and only pay for it.

2,PAAs(Platform as a service, platform as a service) provides an infrastructure where software developers can build new applications or expand existing applications, at the same time, you do not have to purchase development, quality control, or production servers. Salesforce.com's force.com, Google's app engine, and Microsoft's azure (Microsoft's cloud computing platform) all adopt the PAAs model. These platforms allow companies to create personalized applications, as well as independent software vendors or other third-party organizations to create new solutions for vertical sub-sectors.

3,SAAS(Software as a service, software as a service) is the most mature and famous, and also the most widely used cloud computing. You can think of it as a software distribution mode. In this mode, the application software is installed in the vendor or service supplier, and users can use the software through a network, the common network is the Internet. This model is also called "on demand" software, which is the most mature cloud computing model, this mode is highly flexible, proven to be reliable, and scalable, so it can reduce maintenance costs and investment, in addition, the operating costs are also reduced due to the multi-purpose infrastructure of this model. Salesforce.com, netsuite, Google's Gmail, and spscommerce.net are examples of this.

As a matter of fact, as I have said so much, I will summarize that cloud computing is elastic computing.

In addition, cloud computing also has a very important function, that is, it can help us build many physical computers into a powerful supercomputer. What does it mean? That is to say, you want to install a Windows system, which uses 0.1 billion CPUs and 0.2 billion memory. Can you install it? It is estimated that the computer city cannot buy such a computer? However, cloud computing can do this, such as using openstack and cloudstack.