Application of Local Area Network Based on Packet-filtering

On the basis of local area network design and relative research,this paper presents network security firewalls concerning packet-filtering control technology with which data on the internet can be taped when setting off IP address,TCP/UDP port and contract category features.The rules in filtering controlling on network security firewalls are only conducted by manager.With defining packet-filtering technologies and describing the rules underlying packet-filtering control on network security firewalls,this paper renders the logical principles of network security firewalls design,principal data structure and finally give an account of the major functional module.