In 2006, Google launched the "Google 101 Program" and formally proposed the concept and theory of "cloud." Then Amazon, Microsoft, Hewlett-Packard, Yahoo, Intel, IBM and other companies have announced their "cloud plan", cloud security, cloud storage, internal cloud, external cloud, public cloud, private cloud... a bunch of dazzling concepts Constantly impacting people's nerves. So what exactly is cloud computing technology? Where is the generation, concept, principle, application and prospect of cloud computing technology?

First, the generation of cloud computing ideas

In the traditional mode, an enterprise building an IT system requires not only the purchase of hardware and other infrastructure, but also the license to buy software, which requires specialized personnel maintenance. As the company expands, it will continue to upgrade various hardware and software facilities to meet the needs. For enterprises, hardware and software such as computers are not what they really need. They are just tools to get the job done and provide efficiency. For individuals, we want to install a lot of software for normal use of the computer, and many of the software is chargeable. It is very uneconomical for users who do not use the software frequently. Can we have such a service and can provide all the software we need for us to rent? In this way, we only need to pay a small amount of "rent" to "rent" to these software services, saving us a lot of money to buy hardware and software.

We use electricity every day, but we don't have every own generator. It's supplied by power plants. We use tap water every day, but not every one has a well, it is concentrated by the waterworks. This model has greatly saved resources and facilitated our lives. In the face of the troubles that computers bring us, can we use computer resources like water and electricity? These ideas eventually led to the emergence of cloud computing.

The ultimate goal of cloud computing is to provide computing, services, and applications to the public as a public facility, enabling people to use computer resources like water, electricity, gas, and telephone.

The cloud computing mode is the centralized power supply mode of the power plant. In the cloud computing mode, the user's computer will become very simple, perhaps not much memory, no hard disk and various application software, can meet our needs, because the user's computer in addition to sending a "cloud" through the browser You can use the cloud service provider's computing resources, storage space, and various application software to basically use nothing outside of the command and acceptance data. This is like connecting the "display" and "host" wires to an infinite length so that the display can be placed in front of the user, and the host is placed far away from the computer user even. Cloud computing turns the wires that connect the "display" and "host" into a network, turning the "host" into a server cluster of cloud service providers.

In the cloud computing environment, the user's concept of use will also undergo radical changes: from "buy products" to "purchase services", because they will not face complex hardware and software, but the final service. . Users do not need to have visible and tangible hardware facilities, and do not need to pay for equipment room power supply, air conditioning, refrigeration, special maintenance, etc., and do not have to wait for long lead times, project implementation and other lengthy time, Simply remit the money to the cloud computing service provider and we will get the services we need right away. two,

Second, the concept of cloud computing

Cloud CompuTIng is developed by Distributed CompuTIng, Parallel CompuTIng, and Grid CompuTIng. It is an emerging business computing model. At present, the understanding of cloud computing is constantly changing, and there is still no universally consistent definition of cloud computing.

Liu Peng, a cloud computing and cloud computing expert in China, gave the following definition: "Cloud computing distributes computing tasks across resource pools made up of a large number of computers, enabling various application systems to acquire computing power, storage space, and various software services as needed." .

Narrow cloud computing refers to vendors building data centers or supercomputers through distributed computing and virtualization technologies, providing data storage, analytics, and scientific computing services to technology developers or enterprise customers for free or on-demand leases, such as Amazon. Data warehouse rental business.

Broad-based cloud computing refers to the establishment of network server clusters to provide different types of services such as online software services, hardware leasing, data storage, and computational analysis to various types of customers. Cloud computing in a broad sense includes more vendors and service types, such as online financial software launched by management software vendors such as domestic UFIDA and Kingdee, and Google application suites released by Google.

The popular understanding is that the cloud of cloud computing is the resource that exists on the server cluster on the Internet. It includes hardware resources (server, memory, CPU, etc.) and software resources (such as application software, integrated development environment, etc.), local. The computer only needs to send a demand message via the Internet. There will be thousands of computers at the remote end to provide you with the resources you need and return the results to the local computer. This way, the local computer needs almost nothing to do, all the processing is in The computer cluster provided by the cloud computing provider is completed.

Third, the main service forms and typical applications of cloud computing

Cloud computing is still in its infancy, and there are a variety of vendors developing different cloud computing services. Cloud computing has many forms of expression. Simple cloud computing can be seen everywhere in people's daily web applications, such as online production of Flash images provided by Tencent QQ space, Google's search service, Google Doc, Google Apps and so on. At present, the main service forms of cloud computing are: SaaS (Software as a Service), PaaS (Platform as a Service), IaaS (Infrastructure as a Service).

(1) Software as a Service (SaaS)

The SaaS service provider deploys the application software on its own server, and the user subscribes the application software service to the manufacturer through the Internet according to the demand. The service provider charges according to the quantity of the software set by the customer, the length of time, and the like, and the user is charged through the browser. Provide the mode of the software. The advantage of this service model is that the service provider maintains and manages the software and provides the hardware facilities for the software to run. Users only need to have a terminal that can access the Internet, so they can use the software anytime, anywhere. In this mode, customers no longer spend a lot of money on hardware, software, and maintenance personnel as in the traditional model. They only need to pay a certain amount of rental service fees, and they can enjoy the corresponding hardware, software, and maintenance services through the Internet. This is the network. Apply the most efficient operating model. For small businesses, SaaS is the best way to adopt advanced technology.

In terms of enterprise management software, the cloud computing ERP in SaaS mode allows customers to pay service fees on demand according to different combinations of concurrent users, functions used, data storage capacity, and length of use, without paying software license fees. There is no need to pay for hardware equipment such as purchasing servers, and there is no need to pay for the purchase of operating system, database and other platform software costs, nor for software project customization, development, implementation costs, or IT maintenance department expenses, in fact, cloud computing ERP is the most important feature that inherits the open source ERP license-free fee and only charges the service fee. It is an ERP product that highlights the service.

Currently, Salesforce.com is the most famous company to offer such services, and Google Doc, Google Apps and Zoho Office are also such services.

(2) Platform as a Service (PaaS)

Provide the development environment as a service. This is a distributed platform service. Vendors provide services such as development environment, server platform, and hardware resources to customers. Users can customize and develop their own applications based on their platforms and deliver them to other customers through their servers and the Internet. PaaS provides enterprises or individuals with a middleware platform for R&D, providing application development, databases, application servers, testing, hosting and application services.

Google App Engine, Salesforce's force.com platform, 800-800's 800APP is the representative product of PaaS. Take Google App Engine as an example. It is a platform consisting of python application server group, BigTable database and GFS. It provides developers with an integrated host server and an automatically upgradeable online application service. Users write applications and run on Google's infrastructure to serve Internet users, and Google provides the platform resources needed to run and maintain applications.

(3) Infrastructure Services (IaaS)

IaaS provides the vendor's "cloud" infrastructure consisting of multiple servers as a metering service to customers. It consolidates memory, I/O devices, storage and computing power into a single virtual resource pool to provide the entire industry with the storage resources and virtualized servers needed. This is a hosted hardware approach where users pay for the vendor's hardware. For example, Amazon Web Services (AWS), IBM's BlueCloud, etc. all lease infrastructure as a service.

The advantage of IaaS is that users only need low-cost hardware to rent the corresponding computing power and storage capacity on demand, which greatly reduces the hardware overhead of users.

Currently, the most representative of Google cloud applications, such as GoogleDocs, GoogleApps, Googlesites, cloud computing application platform GoogleApp Engine.

GoogleDocs is the first cloud computing application to be introduced, and is a typical application of software-as-a-service thinking. It is an online office software similar to Microsoft's Office. It can process and search documents, forms, slides, and share and set sharing permissions with others over the web. Google Docs is a web-based word processing and spreadsheet program that increases collaboration efficiency. Multiple users can change files online at the same time, and can see edits made by other members in real time. Users only need a computer with Internet access and a standard browser that can use Google files to create and manage online, real-time collaboration, rights management, sharing, search capabilities, revision history, and access anytime, anywhere. Improved sharing and collaboration capabilities for file operations.

Google Apps is Google Apps, enabling users to handle the sheer volume of information, stay connected, and communicate, share, and collaborate with other colleagues, customers, and partners. It integrates Cmail, GoogleTalk, Google Calendar, GoogleDocs, and the latest cloud applications GoogleSites, API extensions and some management functions, including communications, collaboration and publishing, management services, and cloud computing features. Can better achieve collaborative sharing anytime, anywhere. In addition, it has the advantage of low cost and convenient hosting, users do not need to maintain and manage the built-in collaborative sharing platform.

Googlesites is Google's latest cloud computing app, appearing as a component of GoogleApps. It's a site-editing tool that focuses on teamwork, and it can be used to create a variety of team sites that can use Googlesites to include all types of files, including documents, videos, photos, calendars, and attachments, with friends, teams, or the entire network. share it.

Google AppEngine is a platform released by Google in April 2008 that allows users to develop and deploy their own applications on Google's infrastructure. Currently, Google AppEngine supports the Python language and the Java language. Each Google AppEngine application can use up to 500MB of persistent storage space and support bandwidth and CPU of 5 million page views per month. And, the Google AppEngine application is easy to build and maintain, and scales easily based on user traffic and data storage needs. At the same time, the user's app can be integrated with Google's app, and Google AppEngine also introduces a software development kit (SDK) that includes a web server application that emulates all Google AppEngine services on the user's local computer.

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