The firewall is the security system in-between the inside and outside network,responsible for controlling the visit to resources. The filtration technology of the firewall, the detection technique of the state, and the security weakness i n Internet of agent's technology are analyzed in detail. The topologi cal structure of the network, the disposition of firewall, and the influence of the borderline environment of the network security to the firewall are described . Authors suggest that when building firewall, the principle of security assessm ent from both outside and inside the firewall, so...
