Abstract: A system and method for filtering of web-based content in a proxy cache server environment provides a local network having a client, a directory server and a proxy cache server that caches predetermined Internet-derived web content within the network. When content is requested, it is vended to the client only if it meets predefined user policies for acceptability. These policies are implemented based upon one or more ratings lists provided by content rating vendors. The lists are downloaded to the network in whole or part, and cached for use in determining acceptability of content by a filter application. Ratings can be particularly based upon predetermined content categories. Caching occurs in a host or object cache for rapid access. Only if current ratings are not found in the host or object caches are ratings caches or vendors accessed for ratings. Ratings on requested content are then placed in the host or object cache for subsequent use.

Abstract: The restriction of particular resources includes providing a digital signature for unauthorized resources based on a structure-related parameter of the resource. Thus, attempts at circumventing recognition of such resource will likely result in altering the overall functionality of the resource. Further, such digital signatures are encoded in a critical file required for loading of a resource, thus ensuring that the identity of the resource is considered before execution thereof. Enforcement of the resource restriction includes generating a verification signature for a resource that requests loading. The verification signature is compared to the signature coded into the critical file, and a positive match results in the resource being blocked from loading.

Abstract: A system and method for filtering of web-based content in a proxy cache server environment provides a local network having a client, a directory server and a proxy cache server that caches predetermined Internet-derived web content within the network. When content is requested, it is vended to the client only if it meets predefined user policies for acceptability. These policies are implemented based upon one or more ratings lists provided by content rating vendors. The lists are downloaded to the network in whole or part, and cached for use in determining acceptability of content by a filter application. Ratings can be particularly based upon predetermined content categories. Caching occurs in a host or object cache for rapid access. Only if current ratings are not found in the host or object caches are ratings caches or vendors accessed for ratings. Ratings on requested content are then placed in the host or object cache for subsequent use.