Traditional rate control protocols for networks such as TCP require cooperation between traffic sources to achieve optimal network performance. However, traffic sources may not be cooperative due to a widely heterogeneous demand of end-users. We propose a flow rate control framework using noncooperative game theory. The scheme is based on the idea of the Stackelberg solution from noncooperative game theory. The network as a leader designs a pricing mechanism for network bandwidth that attempts to drive the users? flow to the social optimal solution. Each user as a follower is charged by network, and chooses a willingness-to-pay to maximize his own net profit. We prove that the rate control game admits a unique Stackelberg equilibrium point and the bandwidth allocation is efficient and fair.