Security plays a key role in every stage of an application, from the design, to development, to deployment, and into daily use. Struts does not offer any specific security features, as it relies on the security built into the JSP/Servlet and J2EE frameworks. The J2EE framework does offer basic authentication and authorization services; however the exact implementation is often dependent on the J2EE server. On the other hand, the .NET Framework, and ASP.NET in particular, offer many advanced security features that go above and beyond such simple tasks as authentication and authorization.
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ASP.NET and Struts: Web Application Architectures