有人问过我关于云计算的安全问题，指出将信息存放在云里面，不能很好的保证信息的安全性，毕竟和存放在自己可以掌控的范围内截然不同。
确实大家这样说，是存在误区的。因为对于大家的理解，都认为，云计算的安全是指，将自己的数据，服务等存放在公共的云计算服务中。其实，云计算不是这样的。云计算本质是对原有的电脑服务架构进行革新，产生另外的系统架构，彻底颠覆以前系统架构存在的效率问题。
云计算的分类有三种：
There are three main types of cloud deployment models -public, private and hybrid clouds.
Public Clouds – are the most common type of cloud. This is where multiple customers can access web applications and services over the internet. Each individual customer has their own resources which are dynamically provisioned by a third party vendor. This third party vendor hosts the cloud for
multiple customers from multiple data centers, manages all the security and provides the hardware and infrastructure for the cloud to operate. The customer has no control or insight into how the cloud is managed or what infrastructure is available.
Private Clouds – emulate the concept of cloud computing on a private network. They allow users to have the benefits of cloud computing without some of the pitfalls. Private clouds grant complete control over how data is managed and what security measures are in place. This can lead to users having more confidence and control. The major issue with this deployment model is that the users have large expenditures as they have to buy the infrastructure to run the cloud and also have to manage the cloud themselves.
Hybrid Clouds – incorporate both public and private clouds within the same network. It allows the organisations to benefit from both deployment models.
For example, an organisation could hold sensitive information on their private cloud and use the public cloud for handling large traffic and demanding situations.
将不是特别重要的数据可以存放在公有云上；将特别重要的数据存放在私有云上，防止公有云存在的问题。