Cloud computing and distributed computing

Cloud computing is "a" a style of computing where massively scalable it-related capabilities are ' as a service ' provided the Internet to listbox external customers using Internet technologies. " That is, cloud computing is the use of Internet technology to integrate information technology capabilities into a vastly scalable way to provide services to multiple external customers as a way of computing. Too round the mouth, say white a bit. Cloud computing is a way of computing the leasing services of users, which should be available everywhere, and (because they can be extended on a large scale) should be very inexpensive.

But with the Internet technology to connect a large number of servers to provide rental computing services, this is what new? In other words: A large distributed computing network with a front-end billing server (see below), so that the distributed computing into the cloud? Of course not! Or else I'm going to paint a cloud in the diagram below that represents distributed computing.

　　

Cloud computing has an extensible computing resource integration approach. So we can also think of cloud computing as customizing a virtual computer for users. When it comes to virtual computers, we usually think of the virtual machine architecture that the following diagram illustrates. The Virtual Machine Monitor (VMM) is an important part of virtualization technology. The main function of VMM is to turn hardware resources into virtual resources. There are many benefits to turning hardware resources into virtual resources, and I'm not going to list them here. Only one: sometimes virtual resources are better than real hardware resources, as we all know that virtual memory can be much larger than the amount of memory the hardware can provide. However, the virtual machines that are joined in the diagram below are still unable to integrate the user-tailored virtual computers needed for cloud computing. The key is that the usual virtualization approach takes into account only virtual individual hardware resources, and then joins the virtual, single computing environment. This is still not the idea of the distributed computation shown above.

　

The virtualization technology required for cloud computing must be virtual architecture technology. Simply put, the connection should be considered at the level of the VMM group. As a result, the virtualization of hardware resources does not have to be limited to a single hardware resource. The following figure (Source: VMware founder Mendel Rosenblum) gives a hint of virtual architecture technology. On such a virtual architecture, an application's request for hardware resources can be limited to the same physical hardware resource. This integrated virtual computer can be truly tailored to the user.