A flexible security model for using Internet content

Java applets, Netscape plug-ins and ActiveX controls have led to the popularization of a new paradigm: extensive downloading of executable code into applications to enhance the functionality of the desktop. One of the problems with this paradigm is the need to control the access rights of the downloaded content. In this paper, we describe a system for downloading content from the Internet and controlling its actions on a client machine. Our system generates a protection domain for the downloaded content dynamically rising the content´s requested domain and a policy database that describes the user´s trust in the content´s manufacturer and type. Our system ensures that this protection domain is enforced throughout the execution of the content. We have modified the Java Virtual Machine to implement our security model. Our implementation, called Flexxguard, is freely available at http://www.alphaworks.ibm.com