13. A system for screening incoming data of a network, comprising: an analyzing module to analyze the relationships between a plurality of existing rules in a rule set of a firewall used to screen the incoming data of the network, wherein the relationships include cause interactions and effect interactions among the existing rules; a representation module to create a representation of the relationships including the cause interactions and effect interactions; a receiving module to receive a new rule to be inserted into the rule set; a new rule analyzing module to analyze if a conflict is created by insertion of the new rule in the rule set by inserting further relationships between the new rule and the existing rules to create a modified representation and determining if a conflict is created based on the modified representation; and a display to display the representation and the modified representation to a user of the system.
19. The system of claim 13 , wherein the new rule analyzing module suggests, when the conflict is identified, a new placement for the new rule within the rule set.