The Design Of The Hardware Firewall Based Stateful Inspection

With internet application popularizing,the network have been the mainplatform with exchange information.Information security problem in the networkhas been not only paid attention by individuals and companies of networkinformation society increasingly,but also involved in all aspects.For buildingreliable and secure information networks,it is of great necessity and urgency tomake research on security technonlogy.The firewall technonolgy,which has cometo be used since1990s as a kind of network security technonolgy,has beenimproved continuously within more than thirty years.It expericed PacketFiltering Firewall,Circuit Level Firewall,Applicaion Layer Firewall,and StatefulInspection Firewall.The paper gives an introduction to the composition of hardware firewall,which processes received network data packet by network interface chip.Technologies involved include status inspection technology and packet-filteringtechnology. Status inspection technology refers to judgement of informationcontained in the network data packet that is in effective connection status andmonitored by the firewall. The judgement will be based on comparisons betweeninformation of the current and previous data packets, to obtain the controlinformation of that data packet so that the internal network can be protected.Packet-filtering technology is a supplement to status inspection technology,allowing regular inspection over data packets that are not included in the statustable for the convenience for future work on data packet.The paper takes advantage of the technological strength of IP core ofdesigned network chip RTL801of FPGA board and IP core of packet-filteringtechnology, so as to greatly reduce the difficulty in design. In the meanwhile, itcombines FPGA board and PC and brings to full play the status inspectiontechnology of PC to finish the design of status inspection design module ofhardware firewall.