The principle and basic programming syntax of firewall tool―netfilter/iptables and traffic control tool―Traffic Control(TC) based on Linux are analyzed. According to features of small-scale Local Area Network(LAN), a network management system is proposed. This system implements packet filtering and network IP address translation by iptables, and implements traffic control by Hierarchical Token Bucket(HTB)-based TC. Test results indicate that the proposed system based on iptables and TC can effectively protect network security, reasonably constrain the bandwidth of network devices and ensure quality of services.