Design And Implementation Of Firewall Toolkit Based On Linux

With the rapid development of computer network technology, the Internet have brought important influence on every realm of the politics and economy. At the same time, problems on network security are increasingly serious and more and more arouse attention of people.Firewall technology, which is one of the cardinal technologies for protecting network, can be used to isolate organization's private network from Internet and exempt it from invasions which come from Internet. In China, developing firewall products with entire intellectual property have significant value for network security.In this paper, a firewall toolkit named Leacher is implemented on Linux platform. This toolkit of firewall apply packet filtering and application proxy technology synthetically and have entire intellectual property.Specifically, the contribution in this paper includes: The design and implementation of the firewall toolkit which use packet filtering technology and application proxy technology synthetically. This firewall toolkit, including functions of packet filtering, address masquerading, transparent proxy, FTP application proxy, HTTP application proxy, Telnet application proxy and ect, is a complete firewall product and fit to a wide variety of demandes of users. The presentation and implemention of a index technology which increase the speed of rule retrieval. The index technology improve the responsespeed of firewall and resolve the problem of bandwidth occupancy bynormal firewall at condition of long rule table. The presentation and implementation of a interaction mechanism betweenfirewall and IDS. By this mechanism, policies of firewall can be modifieddynamicly and the adaptivity of the firewall are improved. The design and implementation of administration tools of firewall basedon GUI. The tools facilitate the administration.