In this paper we study resilience of TDMA-based wireless sensor networks to node failures. We investigate exploiting mutlicast routing for providing redundancy in the number of gateways used by data streams, so as to protect them against gateway failures. To do this, we develop an optimization model aiming at packet traffic throughput maximization composed of three mixed-integer programming problem formulations and corresponding solution algorithms. The first formulation assumes predefined multicast routing trees and fixed gateway locations, and optimizes the TDMA frame composition. The second one adds routing trees optimization, while the third formulation additionally includes optimization of gateway locations. We present a numerical study illustrating effectiveness of our model, including efficiency of the solution algorithms. Our results show that substantial gains in traffic throughput can be obtained by including routing trees optimization and optimal gateways selection, especially for high levels of redundancy.

在本文中，我们研究了基于TDMA的无线传感器网络对节点故障的恢复能力。我们调查了利用mutlicast路由来提供数据流使用的网关数量的冗余，从而保护它们免受网关故障的影响。为此，我们开发了一种针对数据包流量吞吐量最大化的优化模型，该模型由三种混合整数编程问题公式和相应的求解算法组成。第一种公式假定预定义的多播路由树和固定的网关位置，并优化TDMA帧组成。第二个增加了路由树的优化，而第三个公式另外包括了网关位置的优化。我们提供了一个数值研究，说明了我们模型的有效性，包括求解算法的效率。