1.9. Performance and Security Considerations

Just as you are concerned with the performance and security of your ASP.NET web applications, you will need to take similar precautions to ensure that your important data is protected from abuse while you're using Silverlight 2 to its full potential. There are a few ramifications for taking web presentation development out of the ASP.NET server and into the Silverlight 2 client. Let's cover a few of these so that you're prepared to handle them when you begin writing your own Silverlight 2 applications.

1.9.1. No Reliable Measure of Client Performance

It is the user's computer that is now responsible for executing the code that creates your application's UI and provides behaviors, animations, and service layer communication. This means that if you introduce a memory leak, it's your users' memory that's leaking, which could have adverse effects on their browsing experience with other sites, and not simply your own. In ASP.NET development, the server is solely responsible for creating content that is delivered to the browser as HTML; if you suffered from performance problems here, they were down on the server, where they could be profiled and improved. This isn't to say that you do not need to address performance issues when working with ASP.NET applications that rely heavily on client-side scripting technologies like AJAX, or Web Service calls that could introduce similar memory leaks, but if you are accustomed to server-centric web development, it's worth noting that much of your logic now lives in both the client and server worlds. You have the added consideration now to remember that not all client hardware is created equal, and that amazing 3D photo rotation you wrote for your fast development machine, when executed on the average user's machine, might be too slow to use effectively.