About virtualization and cloud computing

For a long time, I have been paying attention to virtualization and cloud computing technologies. I have read a lot of materials and have gone through some research and practices, I have always wanted to give a brief summary of what I have seen and what I have done. I am helpless because I have no time or I am not in that mood.
I have heard a teacher say: "learning is a concept." Sometimes it is true that I want to think about it in most cases. When virtualization is mentioned in the industry, there will always be questions about virtualization and cloud computing. I have the same question, but it is still true. Even so, the industry has elaborated on these two concepts. On Wikipedia, this is described as follows: "virtualization representsAbstract methods of computer resourcesThrough virtualization, you can access abstract resources in the same way as accessing abstract resources. This resource abstraction method andPhysical configuration of implementation, address location, or underlying resources is not restricted"" Cloud computing is a wayDynamic ScalingOfVirtualizationResource passInternetToServiceProvided to the userComputing ModeUsers do not need to know how to manage infrastructure that supports cloud computing ".
Common types of virtualization include server virtualization, network virtualization, storage virtualization, desktop virtualization, and application virtualization. server virtualization includes CPU virtualization, Io virtualization, and memory virtualization. From the virtualization concept above, it is easy to understand these virtualization types. They are all divided by different computer resources. Virtualization technology is the most basic and indispensable technology for modern data centers. The finished virtualization technology is called virtual devices. Virtual Devices are what we call virtual machines. The formats of Virtual Devices provided by different virtual device providers are often different, even the Virtual Devices provided by the same vendor may be different. Currently, general manufacturers can provide a complete set of virtualization solutions, virtualization solutions often include how to create, manage, migrate, deploy virtual devices, and implement centralized monitoring, optimization, and backup of Virtual Devices. Common virtualization product providers include VMWare, Microsoft, IBM, and xen. Compared with other vendors, IBM is able to provide a complete set of virtualization solutions (including hardware and software) for enterprises, data centers, and other large organizations ), several other companies only provide software-level solutions (including the production and management of virtualization devices ).
From Wikipedia's definition of cloud computing, it is not difficult to see that virtualization is the foundation of cloud computing. At the same time, cloud computing has more connotations, this includes how to achieve dynamic scaling of virtualized resources and how to provide services to users. The development of cloud computing is no longer simply a technology, but more a business model, and this business model is proving to be successful, especially abroad. The direct driving force of cloud computing technology includes the rapid development of hardware technology, such as chip and storage technology, as well as the development of software technology, such as SOA, Web2.0, and Internet technology. At present, cloud computing providers have basically reached a consensus to divide cloud computing technologies into three layers: Infrastructure as a service (IAAS) and platform as a service (PAAs, platform as a service, software as a service (SAAS ). At different levels, the focus of cloud computing technology varies. IAAs focuses on how to use virtualization technology to achieve rapid deployment, dynamic resource scheduling, and provision to end users through internet services. Major IAAs users are large and small organizations and developers, IAAs provides services such as online computing and storage (such as virtual machines) and private cloud. Common products include Amazon EC2; PAAs focuses on all aspects of paas, except for providing Internet services, PAAs focuses on how to apply traditional computer operating system concepts and technologies to the cloud computing framework based on virtualization technology, the true implementation of the cloud Operating System (usually refers to the server operating system that integrates web servers and database servers) provides computing services, storage services, message and communication services, etc, in many cases, Cloud Technologies such as SQL Azure, which provide data management services, are also included in Paas. Common products include Windows Azure, sale force, and Amazon SWS (relatively speaking, windows azure can better reflect the basic concepts of PAAs). SaaS focuses on how to pass traditional application software through The Internet is provided to end users in the form of services. SaaS can be deployed on IAAs or Paas. The difference is that if the architecture is deployed on IAAs, some PAAs technologies need to be implemented, if the architecture is on pass, it can focus more on the business rather than the technology as traditional applications do. Currently, the advantages and disadvantages of the two implementation methods depend on the situation, common products include office online, Lotus live, and Windows Live. Technologies serve businesses, and cloud computing is more about a new business model. When talking about business, we naturally need to talk about money. Therefore, it is a great challenge for cloud computing vendors to develop billing rules.
As a developer, we focus more on how to use these cloud platforms to implement cloud applications. Compared with traditional applications, cloud applications and Internet technologies are more closely integrated. Therefore, when developing cloud applications, we should consider the design of cloud applications from the Web perspective, this includes security, scalability, availability, and performance. All in all, good cloud applications should have all the characteristics of contemporary web application architecture. Compared with the contemporary web application architecture, cloud applications should put security at the highest priority. There is no doubt that many vendors have reached a consensus. Currently, cloud application development platform providers mainly include Google, Microsoft, Amazon, and salesforce.com.