Ajax accelerates Web applications

Ajax|web

At present, the IT industry relies more and more on web systems in providing business applications. Although web browsers have always been an ideal and inexpensive way to provide software to remote users, they do not provide rich client functionality like desktop applications. Ajax (Asynchronous JavaScript and XML) enables rich client interaction and real-time data micro-update (micro-update) and does not require the use of any proprietary proprietary plug-ins.

Ajax is a web development technology that uses most browser-built tools, and contains three components, the JavaScript used for computation, the ECMA Script, the Dynamic HTML for representations, and the XML HTTP for client/server communication.

The key component of Ajax is XML HTTP. When it is downloaded to the client browser, it is possible to quickly communicate between the Web page and the server, instead of having to reload the entire Web page in the case of the client-server communication with the traditional web-based model.

This may seem simple, but it opens a long, dusty door for Web application developers. In addition to the components built into the browser, it does not have to rely on anything else. Because some enterprises pay special attention to the security and logistical problems that a user may have when installing software, Ajax does not need to release any software to the user, so it also arouses the great interest of this kind of enterprise.



The traditional Web application architecture (sometimes called the postback model) is inefficient because it wastes a lot of communication bandwidth. Each time a user clicks on the hyperlink, a postback (that is, reload) the entire Web page appears. In fact, reloading all of these projects may not be necessary, and perhaps just a small piece of text from the database will solve the problem.

With XML HTTP and JavaScript, developers can request a chunk of information asynchronously from the server without reloading the entire page. This allows Web applications to react more quickly to user interactions.

Suppose a user might want to view the details of a customer through a Web page. In a traditional Web application, the user must wait for the Web page to refresh after a click, and the user will be able to see the details of the customer only after this step is completed. But in the AJAX model, users can retrieve the customer's data immediately from the server by clicking on the customer's name, and then the data is displayed directly on the Web page.

XML HTTP can also solve the problem of real-time data in the traditional web-based application model. When a Web page containing some data is downloaded to the browser, the data is considered obsolete. It is not possible for the browser to know whether the data on the server has changed or is still accurate. This problem becomes even more pronounced when a Web application has multiple users at the same time. And if Ajax is used, it can be checked before the user uses the data to avoid this problem.

Ajax is now supported by all major browser platforms, including Internet Explorer, Mozilla FireFox, Netscape, opera, and Safari. There are also many development efforts that are trying to standardize XML HTTP. Last year, the 3W consortium formed a Web API workgroup dedicated to the specification development of HTTP features (partly Ajax). It is because of the extensive support of Ajax in the IT industry that the team attaches so much importance to the development of the specification.

By performing targeted information updates (or micro-updates), it is sufficient to significantly reduce network load and enable faster interaction and communication with real-time data. We can measure the benefits of this approach by calculating the total number of bytes transferred, the total download time, and how many steps can be performed per second when a task is completed.

The role of Ajax has become increasingly important and more pronounced, and it has been used in heavyweight applications such as Google Maps and Salesforce.com, as well as in large and small businesses. Its rapid growth suggests that the way companies build future Web applications is undergoing profound changes.