A new routing metric for wireless mesh networks

In Wireless Mesh Networks the main goal is to achieve the best possible quality and efficiency of data transmission between source and destination nodes. To achieve such transmission, a routing algorithm should select better paths by taking the quality of wireless links into account. Simple path selection based on minimal hop count often leads to poor performance due to the fact that paths with low hop count often have higher packet loss rates. Better paths can be obtained by characterizing the actual quality of wireless link. A number of link quality aware routing metrics such as Expected Transmission Count (ETX), Expected Transmission Time (ETT), Weighted Cumulative Expected Transmission Time (WCETT), Metric of Interference and Channel Switching (MIC), Interference Aware Metric (iAWARE) etc have been explored. This study highlights some shortcomings of these routing metrics and proposes the design of a novel metric called ETX-3hop, which addresses the discussed weaknesses and works more efficiently under various link quality conditions. ETX-3hop consists of a more accurate method to measure the link quality and a path metric that better captures the quality of a path. The performance of the ETX-3hop metric is compared against the original ETX with different path metrics. In extensive simulations, ETX-3hop metric outperforms the original ETX metric in terms of network throughput.