Virtualization supports infrastructure level storage technology to get rid of hardware device limitations, better scalability, programming mode to ensure good user experience processing technology, ensure data storage and access resource management, and ensure the stability and security of system state are the first three deployment modes: public cloud, private cloud and hybrid cloud to improve resource utilization and save a lot of energy.
The emergence of cloud computing makes many people regard it as a new technology, but in fact, its rudiment has appeared for many years, and only in recent years has it begun to achieve relatively rapid development. To be exact, cloud computing is the product of the evolution of large-scale distributed computing technology and its supporting business model. Its development mainly depends on the common development of virtualization, distributed data storage, data management, programming mode, information security and other technologies and products. In recent years, the evolution of business models such as hosting, back charging and on-demand delivery has also accelerated the turning point of cloud computing market. Cloud computing not only changes the way information is provided, but also subverts the traditional delivery mode of ICT system. Cloud computing is not so much a technological innovation as a transformation of thinking and business model.
Let's talk about the core technology of cloud computing in detail.
Cloud computing is a kind of intensive computing mode centered on data and processing capacity. It integrates a number of ICT technologies and is the product of "smooth evolution" of traditional technology. Among them, virtualization technology, distributed data storage technology, programming model, large-scale data management technology, distributed resource management, information security, cloud computing platform management technology, green energy-saving technology are the most critical.
1. Virtualization Technology
Virtualization is one of the most important core technologies of cloud computing. It provides infrastructure support for cloud computing services, and is the main driving force for ICT services to rapidly move to cloud computing. It can be said that without virtualization technology, there will be no cloud computing service landing and success. With the continuous heating of cloud computing applications, the industry's attention to virtualization technology has also been mentioned to a new height. At the same time, our survey found that many people have misunderstandings about cloud computing and virtualization, believing that cloud computing is virtualization. In fact, this is not the case. Virtualization is an important part of cloud computing, but not all of it.
Technically speaking, virtualization is a kind of computing form that simulates computer hardware in software and provides services for users with virtual resources. The purpose of this paper is to allocate computer resources reasonably and to provide services more efficiently. It breaks the physical partition between the hardware of the application system, so as to realize the dynamic architecture and realize the centralized management and use of physical resources. The biggest advantage of virtualization is to enhance the flexibility and flexibility of the system, reduce costs, improve services, and improve the efficiency of resource utilization.
From the form of expression, virtualization can be divided into two application modes. One is to virtualize a powerful server into several independent small servers to serve different users. Second, virtual multiple servers into a powerful server to complete specific functions. The core of these two modes is unified management, dynamic allocation of resources and improvement of resource utilization. In cloud computing, these two modes have more applications.
2. Distributed data storage technology
Another advantage of cloud computing is that it can process massive data quickly and efficiently. In today's data explosion, this is crucial. In order to ensure the high reliability of data, cloud computing usually uses distributed storage technology to store data in different physical devices. This mode not only gets rid of the limitation of hardware equipment, but also has better expansibility and can quickly respond to the changes of user requirements.
Distributed storage is not exactly the same as traditional network storage. Traditional network storage system uses centralized storage server to store all data. Storage server becomes the bottleneck of system performance and can not meet the needs of large-scale storage applications. Distributed network storage system adopts scalable system structure, uses multiple storage servers to share the storage load, and uses location server to locate storage information. It not only improves the reliability, availability and access efficiency of the system, but also is easy to expand.
In the current cloud computing field, Google's GFS and Hadoop's open source system HDFS are two popular cloud computing distributed storage systems.
GFS (Google File System) technology: Google's non open source GFS (Google File System) cloud computing platform meets the needs of a large number of users and provides services for a large number of users in parallel. The data storage technology of cloud computing has the characteristics of high throughput and high transmission rate.
HDFS (Hadoop distributed file system) technology: most ICT manufacturers, including Yahoo and Intel's "cloud" plan, adopt HDFS data storage technology. The future development will focus on large-scale data storage, data encryption and security assurance, and continue to improve the I / O rate.
3. Programming mode
In essence, cloud computing is a multi-user, multi task, concurrent processing system. Efficient, simple and fast is its core concept. It aims to easily distribute powerful server computing resources to end users through the network, while ensuring low cost and good user experience. In this process, the choice of programming mode is very important. Distributed parallel programming mode will be widely used in cloud computing projects.
The original intention of distributed parallel programming mode is to make use of software and hardware resources more efficiently and make users use applications or services more quickly and simply. In the distribution