A method of content filtering of data containers of multiple content types is based on generating a set of encoded filters and a set of encoded rules for each content type. Each encoded filter is expressed as a respective operator, from among user-defined operators, and two operands including a content descriptor and a descriptor criterion. A filter has a binary state and a rule may be based on a single filter or a number of selected filters. An apparatus implementing the method has a user interface for receiving user-defined configuration data, a configuration module for generating a set of encoded filters and a set of encoded rules for each content type, a network interface for receiving data containers from a network and transmitting filtered data containers to the network, and a filtering module for applying the rules to received data containers.