How can AJAX technology save application bandwidth?

Using AJAX to Improve the Bandwidth Performance of Web Applications this article quantifies how AJAX technology can save the Bandwidth of Applications. I compared the results of the two tests in the article with a picture combination: This shows the effect is more obvious.

 

Here are several basic results:
1. Applications that contain ajax are downloaded for the first time, which is larger than applications in the general page refreshing mode: the ajax version of Usage Analyser is 12387 in size and the original size is 9741 bytes.
2. AJAX applications in subsequent interactions: only part of the refresh data needs to be updated 2-3 k, while the traditional full-page refresh mode requires the whole page to be reloaded: About 10 k
3. The more interactions, the more obvious the bandwidth savings of AJAX applications;
4. Although the full-page refresh mode requires re-loading images and so on, the client is notified to use locally cached images and JS images. Therefore, no new traffic is generated,

In this test, ajax technology saved a total of more than 61%. It far exceeds the expected 50%, and the savings rate will be higher as interactions increase.

The formula for converting the proportion of bandwidth saved by AJAX technology compared with that by PAGE swiping:
(Interactions (page interaction traffic-AJAX Interaction Volume)-(added for the first time in AJAX)/(page interaction times + page size loaded for the first time)