The New Web: Characterizing AJAX Traffic
The rapid advent of “Web 2.0” applications has unleashed new HTTP traffic patterns which differ from the conventional HTTP request-response model. In particular, asynchronous pre-fetching of data in order to provide a smooth web browsing experience and ri
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Abstract. The rapid advent of “Web 2.0” applications has unleashed new HTTP traffic patterns which differ from the conventional HTTP request-response model. In particular, asynchronous pre-fetching of data in order to provide a smooth web browsing experience and richer HTTP payloads (e.g., Javascript libraries) of Web 2.0 applications induce larger, heavier, and more bursty traffic on the underlying networks. We present a traffic study of several Web 2.0 applications including Google Maps, modern web-email, and social networking web sites, and compare their traffic characteristics with the ambient HTTP traffic. We highlight the key differences between Web 2.0 traffic and all HTTP traffic through statistical analysis. As such our work elucidates the changing face of one of the most popular application on the Internet: The World Wide Web.
1 Introduction The World Wide Web [1] is one of the most popular applications of the Internet and runs primarily over the HTTP protocol. While HTTP (Hyper Text Transfer Protocol) [2] constitutes the session layer or messaging protocol of the Web, HTML (Hyper Text Markup Language) describes the content and allows authors of web content to connect up web pages through hypertext links or hyperlinks; an idea made popular by Tim BernersLee in the early 1990s and widely used today. In its classical form, users reach other pages or access new data by clicking on hyperlinks or submitting web based forms. In this basic HTTP request-response model each clicked link or submitted form results in downloading a new web page in response to the respective request. The recent popularity of asynchronous communication enabled web sites has caused a significant shift from the classical HTTP request-response model of the Web. This asynchronous communication is commonly executed through AJAX (Asynchronous JavaScript and XML) [3], a compendium of technologies that enable web browsers to request data from the server asynchronously, i.e., without requiring human intervention such as clicking on a hyperlink or on a button. Consequently, HTTP requests are increasingly becoming automated rather than being human-generated. In this paper we use AJAX and “Web 2.0” interchangeably to refer to web applications that use this new paradigm on the Internet. Contemporary web pages often contain embedded request-response functions comprising a JavaScript application engine that automatically executes in the background to asynchronously pre-fetch large quantities of data from the server. This intelligent M. Claypool and S. Uhlig (Eds.): PAM 2008, LNCS 4979, pp. 31–40, 2008. © Springer-Verlag Berlin Heidelberg 2008
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Browser Output Screen (DOM)
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Fig. 1. Comparison of classical with AJAX enabled web applications
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