Abstract: A method and apparatus in a computer system coupled to a network for altering information in said network by the computer system. A process is inserted between two lower layers of the ISO/OSI model. The process then receives a packet from a first layer of the ISO/OSI model, and determines whether a criteria comprising a set of conditions has been determined in the packet. If any of the set of criteria is present in the packet then the packet is transformed into a modified packet according to a predefined action. Then, the modified packet is transmitted to a second layer of the ISO/OSI model. In different embodiments the layers may be either higher or lower relative to one another in order that incoming or outgoing packets be modified. The method may also be performed under control of a user-generated script, or by remote control from another node. The method may also employ user-generated processes for condition (criteria) checking and/or modifications.