Network traffic management is a significant technology to ensure network QoS. At first, this paper analyzes the key technologies of network traffic management, including traffic identification technology and control technology. Then, a strategy of network traffic management system is proposed. To address the deficiencies of mensuration and precision of main network traffic rate control technology TCR, an improved traffic rate control model is proposed. This model makes the rate control more effective and accurate. Finally, a network traffic management prototype system is implemented based on Linux OS and netfilter firewall framework. Experimental test shows the effectiveness and the accuracy of this system.