1. At an engine employing at least one processor and at least one memory device, a method of content filtering of data containers, the method comprising: defining content types; receiving rule identifiers of a set of rules applicable to each content type; determining dependence of at least one rule on at least one other rule; sorting said rule identifiers according to said dependence to produce rule strata specific to said each content type where rules within each rule stratum are independent of each other and rules within each rule stratum beyond a first stratum depend on at least one rule of at least one preceding rule stratum; receiving an array of processor-executable instructions modules, each instructions module corresponding to a rule among said set of rules; receiving from a network a data container having components of different content types; ascertaining for each component a respective content type; and applying rules of rule strata specific to said respective content type to said each component starting with rules of a first rule stratum and proceeding sequentially to selected rules of succeeding rule strata.