Research Of Worm Filtering Technology Based On Internet Security Gateway

The paper introduces some important techniques of firewall and the software frame based on Linux firewall. We make research through analyzing the behavior characteristics and uniform function model of worms. Moreover, we put forward the Internet worm's filtering module basing on firewall. Based on the known worms'features, we use Feature-match technique to prevent worm from expanding into intranet, and guarantee the security for intranet.It is well known that filtering worm in firewall will cost much CPU timeslices and computation resources. So, in order to ensure the filtering performance, we design the module as follows: Firstly, Extract worms'features accurately, and put them into the worms'feature database. Secondly, filter network stream at different layers, and check the different data stream branches efficiently according to different rules and its probability matching worms'features, to ensure normal network streams can be forwarded through firewall as soon as possible to lower the impact to gateway and internet effectively. Through the work in this paper,we try to provide a way to lower worms' damage in internet in theory and in practice.