High bandwidth requirements in multimedia transmission make the efficient use of limited network resource a challenging task, especially when multiple clients make their requests to the server simultaneously. In this paper, we propose a self-adjusted network transmission mechanism for multiple clients. Instead of assigning a fixed bandwidth for each client, the server determines the transmission rate for each client connection according to the buffer packets and playback rate at each client. Transmission rates are adjusted when the total requested bandwidth is larger than the network bandwidth. In addition, the proposed mechanism can minimize the bandwidth allocation and maximize the client buffer utilization. A simulation is performed and the simulation results show that the proposed mechanism can dynamically change the transmission rate for each client to avoid overflow of the client buffer, and achieve the optimal utilization of the limited network resource in multiple client network environments.