Using Ajax to Improve the Bandwidth Performance of Web Applications : “Christopher Merrill over at webperformance.com wrote up an article on the performance impacts of Ajax development in which he measured bandwidth results for an application using full page refreshes vs. Ajax techniques. The Goal In order to test the theory, we decided to see if we could cut the bandwidth use of an application by at least 50%. We selected a rather simple internal data-analysis application. The application consists of a typical page layout with a central section containing the changing content. The header, footer and navigation menu do not change during the application operation. We modified the application so that it can be accessed in either traditional (page-refresh) mode or AJAX mode. We then used our measurement tool (Web Performance Analyzer) to record and analyze the bandwidth utilization of each application. Conclusion In applications that have a significant part of each page containing content that is identical in multiple page requests, using AJAX-style methods to update only the relevant parts of a web page can bring significant bandwidth savings. Using less than 100 lines of javascript, we were able to quickly convert an existing web application to use AJAX page-update methods to drastically reduce (>60%) the bandwidth requirements of our sample application.
