GDist-RIA Crawler: A Greedy Distributed Crawler for Rich Internet Applications

摘要

Crawling web applications is important for indexing, accessibility and security assessment. Crawling traditional web applications is an old problem, for which good and efficient solution are known. Crawling Rich Internet Applications (RIA) quickly and efficiently, however, is an open problem. Technologies such as AJAX and partial Document Object Model (DOM) updates only make the problem of crawling RIA more time consuming to the web crawler. One way to reduce the time to crawl a RIA is to crawl a RIA in parallel with multiple computers. Previously published Dist-RIA Crawler presents a distributed breath-first search algorithm to crawl RIAs. This paper expands Dist-RIA Crawler in two ways. First, it introduces an adaptive load-balancing algorithm that enables the crawler to learn about the speed of the nodes and adapt to changes, thus better utilize the resources. Second, it present a distributed greedy algorithm to crawl a RIA in parallel, called GDist-RIA Crawler. The GDist-RIA Crawler uses a server-client architecture where the server dispatched crawling jobs to the crawling clients. This paper illustrates a prototype implementation of the GDist-RIA Crawler, explains some of the techniques used to implement the prototype and inspects empirical performance measurements.