RIAs are also different from traditional Web applications in that a significant amount of application processing can take place on the client machine, which is the source of the RIAs' performance improvements over traditional Web applications. RIAs are faster because much of their code is executed directly on the user's machine; this is a dramatic difference from the early days of the Web when browsers basically behaved like dumb terminals. Their only real purpose was to accept user input, send it to the server, and display the response. All of the real logic processing took place on the server; now, though, the capabilities of the Web browser have greatly expanded.
Code that runs on the client tier is beyond the control of developer and other teams within the organization who own the code. An attacker can attach one of the many, freely downloadable, debugging utilities to the RIAs component that exists in the Web browser. This allows anyone to infiltrate the source code of the application as it executes. Any secrets in the client code will be plainly visible.
There was a recent case in which a high-profile computer conference's discount code was discovered embedded in the registration application. Unfortunately, the logic for checking and applying the discount code was implemented on the client. Before long, hackers found and used the secret code and left the conference organizers wondering how so many people were getting discounted passes to the show.
QA professionals should not consider looking at source code or using disassemblers out of the scope of their responsibilities. While it is true that, previously, they never had to perform these actions when testing traditional Web applications, RIAs have expanded the scope of the QA's responsibilities. Simple, manual, black box testing of the application through a Web browser is no longer sufficient. In order to ensure security, the QA arsenal must expand to include new tools and processes in order to thoroughly test all aspects of RIAs.
Changing the QA Mindset for Rich Internet Applications