Basic concepts of cloud computing

1. Cloud computing software and hardware

Cloud software: OpenStack (CLOUD keyboard-based System), a collaborative project launched by Rackspace and NASA.

Cloud Hardware: Open computing Projects (Ocp:open Compute project)

2. Why is cloud computing born?

The cloud computing model is the centralized power supply model for power plants. In the cloud computing mode, the user's computer becomes very simple, perhaps small memory, no hard disk and a variety of applications to meet our needs, because the user's computer in addition to the "cloud" through the browser to send instructions and accept data is basically nothing to do can use the cloud service provider's computing resources, Storage space and various application software. This is like connecting "monitor" and "host" wires infinitely long, so you can put the monitor in front of the user, and the host is far away from even the computer users themselves do not know where. Cloud computing connects "monitor" and "host" wires into networks, turning "hosts" into server clusters for cloud service providers.

3. Cloud Computing Basic concepts

Cloud computing (Cloud Computing) is a new business computing model developed from distributed computing (distributed Computing), parallel processing (Parallel Computing), Grid computing (grids Computing). At present, the understanding of cloud computing is constantly evolving, cloud computing is not yet a universally agreed definition.

The popular understanding is that cloud computing "cloud" is the resources on the Internet server cluster, which includes hardware resources (server, memory, CPU, etc.) and software resources (such as application software, integrated development environment, etc.), the local computer only need to send a demand information via the Internet, The remote will have thousands of computers that will provide you with the resources you need and return the results to your local computer, so that the local computer has little to do, and all of the processing is done in the computer cluster provided by the cloud provider.

4. Cloud Computing's main service forms and typical applications

Cloud computing is still in its infancy, with a complex variety of vendors developing different cloud computing services. Cloud computing in a variety of forms, simple cloud computing in People's Daily network applications everywhere, such as Tencent QQ space to provide online production of flash pictures, Google search services, Google Doc, Google Apps and so on. At present, the main service forms of cloud computing are:

SaaS (Software as a Service):

SaaS Service providers deploy applications uniformly on their own servers, where users order applications via the Internet to vendors, based on the number of customer-defined software, the length of time, etc., and provide the software model to customers through the browser. such as Google Doc, Google Apps, Salesforce.com, ERP

PAAs (Platform as a Service):

Provide the development environment as a service. This is a distributed platform services, vendors to provide development environment, server platform, hardware resources and other services to customers, users on their platform to customize the development of their own applications and through their servers and the Internet to other customers. PAAs can provide a middleware platform for enterprises or individuals to develop, provide application development, database, Application Server, test, hosting and application services.

Google App Engine, Salesforce's force.com platform, 800 800APP is a PAAs representative product. Google App Engine, for example, is a platform composed of Python application servers, bigtable databases, and GFS to provide developers with an integrated host server and an online application service that can be upgraded automatically. Users write applications and run on Google's infrastructure to provide services to Internet users, and Google provides the platform resources needed to run and maintain applications.

IaaS (infrastructure as a Service):

IaaS is the manufacturer's "cloud" infrastructure consisting of multiple servers, which is provided to customers as metering services. It integrates memory, I/O devices, storage, and computing capabilities into a virtual pool of resources to provide the entire industry with the required storage resources and virtualized servers. This is a managed hardware approach that users pay to use the vendor's hardware facilities. For example, Amazon Web Services (AWS), IBM's Bluecloud, and so on, are leased infrastructure as a service.

The advantage of IaaS is that users need only low-cost hardware, hire the appropriate computing power and storage capacity on demand, and greatly reduce the cost of the user's hardware.

Currently, Google Cloud applications are most representative, such as Docs, Apps, googlesites, Cloud computing application platform Googleapp Engine.

5. The core technology of cloud computing

Cloud computing systems use a number of technologies, including programming models, data management technology, data storage technology, virtualization technology, cloud computing platform management technology is the most critical.

6. Google's Cloud computing platform

Google's hardware conditions, large data centers, search engine pillar applications, to promote the rapid development of Google Cloud computing. Google's cloud computing is mainly composed of MapReduce, Google File System (GFS), and BigTable. They are the 3 main components of Google's internal cloud computing infrastructure. Google also builds other cloud computing components, including a domain description language and a distributed lock service mechanism. Sawzall is a domain language based on MapReduce, which is devoted to large-scale information processing. Chubby is a highly available, distributed data Lock service, and when a machine fails, Chubby uses the Paxos algorithm to ensure backup.

7. Cloud computing technology development faces the main problem

Although the cloud computing model has many advantages, it also has some problems, such as data privacy, security, software license, network transmission and so on.

• Data privacy issues: how to ensure that the data privacy of the cloud service provider, not to be illegally used, not only need technical improvements, but also need to further improve the law.

• Data security: Some data is the business secret of the Enterprise, the security of data is related to the survival and development of the enterprise. The security of cloud computing data will not solve the impact of cloud computing in the enterprise application.

User habits: How to change the user's use habits, so that users adapt to the network of software and hardware applications is a long-term and arduous challenge.

• Network transport problem: cloud computing services rely on the network, the current low speed and instability, so that the performance of cloud applications is not high. The popularity of cloud computing relies on the development of network technology.