1. A method of analyzing an ordered security rule-set comprising a plurality of rules comprising N≧1 extrinsic rule-fields, the method comprising: upon specifying an extrinsic space constituted by atomic elements corresponding to the values characterizing an extrinsic rule-field, partitioning said specified extrinsic space into two or more equivalence classes, wherein each atomic element in said extrinsic space belongs to one and only one equivalence class; mapping said equivalence classes over the rule-set; and generating a logically equivalent security rule-set, wherein respective rules comprise N−1 extrinsic rule-fields.