Let's take a look at four Web applications on sites where real browsers matter.
These examples highlight how the end-user experience can be captured only with Web performance-monitoring technologies that use a (real) browser:
Accurately Capturing a Web Page with a Real-Browser There are many reasons to do ongoing testing and monitoring with a solution that uses a real-browser rather than an imitation browser.
An important reason is the ability to accurately capture an actual high-fidelity bitmap of the page when an error occurs instead of a reconstructed page.
A bitmap of a page is generated when you take a screenshot of the actual page exactly as it is drawn by the browser.
A reconstructed page attempts to recreate the layout of the page by translating the captured HTML.
Solutions that use imitation-browser testing are forced to capture the HTML of a page when an error occurs, since they do not actually draw or construct the page during the test.
If you use an imitation browser to try to view the page that generated the error, you will get a reconstructed page.
While this works for simple apps, sites that use RIA technologies such as DHTML will not work with imitation-browsers.
A real-browser-testing product captures the exact page that the user sees in a bitmap To capture the Web page exactly as the user would experience it, you need (realbrowser) technology that captures the actual dynamic behavior of the Web site.
When operation managers see a performance issue they want to quickly resolve the problem to reduce the number of users who could be impacted.
An imitation browser that captures individual objects would try to reconstruct this image by assembling objects via HTML, a process that can be error prone and can result in a misleading analysis.
Screen reconstruction would have extreme difficulty displaying the DHTML behavior used by a site like Pottery Barn.
Using an imitation browser is like reconstructing a crime scene from someone's memory of it.
Using (real)browser technology is like using a surveillance camera to take a snapshot of the actual crime scene.
Conclusion: In the upcoming articles, I will expand on the information introduced in this article, will discuss the impact of executing Javascript in a browser
These examples highlight how the end-user experience can be captured only with Web performance-monitoring technologies that use a (real) browser:
- Accurately capturing a snapshot of a Web page with a real-browser
- Measuring the impact of executing JavaScript in a browser
- Detecting Flash plug-ins
- Precisely measuring client execution of VBScript in a real-browser
Accurately Capturing a Web Page with a Real-Browser There are many reasons to do ongoing testing and monitoring with a solution that uses a real-browser rather than an imitation browser.
An important reason is the ability to accurately capture an actual high-fidelity bitmap of the page when an error occurs instead of a reconstructed page.
A bitmap of a page is generated when you take a screenshot of the actual page exactly as it is drawn by the browser.
A reconstructed page attempts to recreate the layout of the page by translating the captured HTML.
Solutions that use imitation-browser testing are forced to capture the HTML of a page when an error occurs, since they do not actually draw or construct the page during the test.
If you use an imitation browser to try to view the page that generated the error, you will get a reconstructed page.
While this works for simple apps, sites that use RIA technologies such as DHTML will not work with imitation-browsers.
A real-browser-testing product captures the exact page that the user sees in a bitmap To capture the Web page exactly as the user would experience it, you need (realbrowser) technology that captures the actual dynamic behavior of the Web site.
When operation managers see a performance issue they want to quickly resolve the problem to reduce the number of users who could be impacted.
An imitation browser that captures individual objects would try to reconstruct this image by assembling objects via HTML, a process that can be error prone and can result in a misleading analysis.
Screen reconstruction would have extreme difficulty displaying the DHTML behavior used by a site like Pottery Barn.
Using an imitation browser is like reconstructing a crime scene from someone's memory of it.
Using (real)browser technology is like using a surveillance camera to take a snapshot of the actual crime scene.
Conclusion: In the upcoming articles, I will expand on the information introduced in this article, will discuss the impact of executing Javascript in a browser