Analyzing and Boosting the Performance of Power-Line Communication Networks

Power-line communications are employed in home network-ing to provide easy and high-throughput connectivity. IEEE 1901, the MAC protocol for power-line networks, employs a CSMA/CA protocol similar to that of 802.11, but is substan-tially more complex, which probably explains why little is known about its performance. One of the key differences be-tween the two protocols is that whereas 802.11 only reacts upon collisions, 1901 also reacts upon several consecutive transmissions and thus can potentially achieve better per-formance by avoiding unnecessary collisions. In this paper, we propose a model for the 1901 MAC. Our analysis reveals that the default configuration of 1901 does not fully exploit its potential and that its performance de-grades with the number of stations. We derive analytically the optimal configuration parameters for 1901; this dras-tically improves throughput and achieves optimal perfor-mance without requiring the knowledge of the number of stations in the network. In contrast, to provide a similar per-formance, 802.11 requires knowing the number of contending stations, which is unfeasible for realistic traffic patterns. Our solution can be readily implemented by vendors, as it only consists in modifying existing MAC parameters. We cor-roborate our results with testbed measurements, unveiling a significant signaling overhead in 1901 implementations