Cloud computing architecture analysis

Cloud computing - at least as an extension of virtualization, the scope of influence has grown. However, cloud computing currently does not support complex enterprise environments. Therefore, cloud computing architecture is on the horizon. Experience shows that before cloud computing matures, we should pay more attention to the details of the system cloud computing architecture. Based on the analysis of some existing cloud computing products and some personal experience, a cloud computing architecture is summarized. The cloud computing architecture can be divided into four layers.

Display layer

This layer of most data center cloud computing architecture is mainly used to display the content and service experience required by users in a friendly way, and will utilize the various services provided by the middleware layer below. There are five main technologies:

HTML: The standard Web page technology is now mainly based on HTML4, but the upcoming HTML5 will promote the development of Web pages in many aspects, such as video and local storage.

JavaScript: A dynamic language for web pages that greatly enriches the functionality of web pages with JavaScript and creates more interactive dynamic pages with JavaScript-based AJAX.

CSS: Mainly used to control the appearance of web pages, and to elegantly separate the content of the page from its presentation.

Flash: The most commonly used RIA (Rich Internet ApplicaTIons) technology in the industry can provide rich web-based applications that are not available in HTML and other technologies at this stage, and it is very good in terms of user experience.

Silverlight: RIA technology from the industry giant Microsoft, although its current market share is slightly lower than Flash, but because it can be programmed using C#, it is very friendly to developers.

middle layer

This layer is built on the ground up. It provides a variety of services based on the resources provided by the infrastructure layer below, such as cache services and REST services, and these services can be used to support the display layer, or directly call the user. There are mainly five technologies:

REST: With REST technology, it is very convenient and elegant to provide some of the services supported by the middleware layer to the caller.

Multi-tenancy: It allows a single application instance to serve multiple organizations, and maintains good isolation and security, and through this technology, can effectively reduce the acquisition and maintenance costs of the application.

Parallel processing: In order to process massive amounts of data, huge X86 clusters are needed for massive parallel processing. Google's MapReduce is a representative of this.

Application server: A certain degree of optimization for cloud computing based on the original application server, such as the Jetty application server for Google App Engine.

Distributed Cache: Through distributed caching technology, not only can the pressure on the background server be effectively reduced, but also the corresponding response speed can be accelerated. The most famous distributed cache example is Memcached.

Infrastructure layer

This layer is to provide the above middleware layer or user with the resources needed for calculation and storage. There are four main technologies:

Virtualization: It can also be understood as a “multi-tenancy” at the infrastructure layer, because virtualization technology enables multiple virtual machines to be built on a single physical server, and full isolation between these virtual machines can be achieved. Not only can the cost of the server be reduced, but also the operating and maintenance costs of the server can be reduced at the same time. The mature X86 virtualization technology includes VMware ESX and open source Xen.

Distributed storage: In order to carry a large amount of data, but also to ensure the manageability of these data, a complete set of distributed storage systems is required.

Relational database: Basically, it is optimized on the basis of the original relational database to make it more adaptable in the cloud.

NoSQL: In order to meet the goals that some relational databases cannot meet, such as supporting massive amounts of data, some companies specifically design a database that is not based on a relational model.

Management

This layer is for the horizontal three-tier service, and provides a variety of management and maintenance technologies for the three layers, mainly in the following six aspects:

Account management: Through good account management technology, it is convenient for users to log in under safe conditions, and it is convenient for administrators to manage accounts.

SLA monitoring: Performance monitoring of virtual machines, services and applications running at various levels so that they can all run under the pre-defined Service Level Agreement (SLA).

Billing management: that is, statistics on resources consumed by each user, etc., to accurately request fees from users.

Security Management: Comprehensive protection of IT[6] resources such as data, applications and account numbers from criminals and malicious programs.

Load balancing: Addressing unexpected situations by distributing traffic to multiple instances of an application or service.

Operation and maintenance management: It is mainly to make the operation and maintenance operations as professional and automated as possible, thereby reducing the operation and maintenance costs of the cloud computing center.

The cloud computing architecture has three layers that are horizontal, namely the display layer, the middleware layer and the infrastructure layer. Through these three layers of technology, it can provide very rich cloud computing capabilities and a friendly user interface. The cloud computing architecture and the other layer are vertical. , called management, exists to better manage and maintain the horizontal three layers.

Display Layer Most of the data center cloud computing architecture layer is mainly used to display the content and service experience required by users in a friendly way, and will utilize the various services provided by the middleware layer below. There are five main technologies: HTML : Standard Web page technology, now mainly based on HTML4, but the upcoming HTML5 will promote the development of Web pages in many aspects, such as video [1] and local storage. JavaScript: A dynamic language for web pages that greatly enriches the functionality of web pages with JavaScript and creates more interactive dynamic pages with JavaScript-based AJAX. CSS: Mainly used to control the appearance of web pages, and to elegantly separate the content of the page from its presentation. Flash[2]: The most commonly used RIA (Rich Internet ApplicaTIons) technology in the industry can provide rich web-based applications that are not available in HTML and other technologies at this stage, and it is very good in user experience [3]. Silverlight: RIA technology from industry giant Microsoft [4], although its current market share is slightly lower than Flash, but because it can be programmed using C# [5], it is very friendly to developers.

The middle layer is built on the ground up. It provides a variety of services based on the resources provided by the infrastructure layer below, such as cache services and REST services, and these services can be used to support the display layer, or directly to the user. Called, and there are five main technologies: REST: Through REST technology, it is very convenient and elegant to provide some of the services supported by the middleware layer to the caller. Multi-tenancy: It allows a single application instance to serve multiple organizations, and maintains good isolation and security, and through this technology, can effectively reduce the acquisition and maintenance costs of the application. Parallel processing: In order to process massive amounts of data, huge X86 clusters are needed for massive parallel processing. Google's MapReduce is a representative of this. Application server: A certain degree of optimization for cloud computing based on the original application server, such as the Jetty application server for Google App Engine. Distributed Cache: Through distributed caching technology, not only can the pressure on the background server be effectively reduced, but also the corresponding response speed can be accelerated. The most famous distributed cache example is Memcached.

The role of the infrastructure layer is to prepare the required middleware layer or user for the computing and storage resources. There are four main technologies: virtualization: it can also be understood as the “multi-tenancy” of the infrastructure layer. Because virtualization technology can generate multiple virtual machines on one physical server, and can achieve complete isolation between these virtual machines, not only can reduce the cost of server acquisition, but also reduce the operation and maintenance of the server. Cost, mature X86 virtualization technology has VMware ESX and open source Xen. Distributed storage: In order to carry a large amount of data, but also to ensure the manageability of these data, a complete set of distributed storage systems is required. Relational database: Basically, it is optimized on the basis of the original relational database to make it more adaptable in the cloud. NoSQL: In order to meet the goals that some relational databases cannot meet, such as supporting massive amounts of data, some companies specifically design a database that is not based on a relational model.

This layer of management is for the horizontal three-tier service, and provides three layers of management and maintenance technologies, mainly in the following six aspects: account management: through good account management technology, can be safe It is convenient for users to log in under the conditions, and it is convenient for the administrator to manage the account. SLA monitoring: Performance monitoring of virtual machines, services and applications running at various levels so that they can all run under the pre-defined Service Level Agreement (SLA). Billing management: that is, statistics on resources consumed by each user, etc., to accurately request fees from users. Security Management: Comprehensive protection of IT[6] resources such as data, applications and account numbers from criminals and malicious programs. Load balancing: Addressing unexpected situations by distributing traffic to multiple instances of an application or service. Operation and maintenance management: It is mainly to make the operation and maintenance operations as professional and automated as possible, thereby reducing the operation and maintenance costs of the cloud computing center. The cloud computing architecture has three layers that are horizontal, namely the display layer, the middleware layer and the infrastructure layer. Through these three layers of technology, it can provide very rich cloud computing capabilities and a friendly user interface. The cloud computing architecture and the other layer are vertical. , called management, exists to better manage and maintain the horizontal three layers.