Available bandwidth characteristics and estimation of in-home power line networks
Bandwidth information is critical to robust real-time multimedia transmission. However, existing bandwidth estimation (BWE) methods developed for the Internet or wireless networks are inadequate for power line networks due to the difference in media access control scheduling policies and channel noise characteristics. In this paper, we investigate the characteristics of in-home power line networks and present a real-time BWE scheme. By connecting different number of power line communication (PLC) modems, we find that the bandwidth is approximately inversely proportional to the number of PLC modems connected. Moreover, PLC modems have different characteristics of crossing different circuits under the same power meter and crossing different power meter under the same transformer. Based on the evaluation of in-home power line networks with multiple streaming, we propose an available bandwidth estimation scheme that estimates the cutoff rate from physical-layer line rate, data transmission rate, packet size, and packet loss rate. This scheme applies an iterative packet probing algorithm to estimate the available bandwidth. Experimental results show that the proposed scheme achieves good estimation accuracy.