Wu Dapeng, Liu Zhenli, Yang Zhigang, Zhang Puning, Wang Ruyan, Ma Xinqiang
School of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
Key Laboratory of Optical Communication and Networks, Chongqing 400065, China.
Sensors (Basel). 2020 Dec 31;21(1):218. doi: 10.3390/s21010218.
With the widespread application of wireless sensor networks (WSNs), WSN virtualization technology has received extensive attention. A key challenge in WSN virtualization is the survivable virtual network embedding (SVNE) problem which efficiently maps a virtual network on a WSN accounting for possible substrate failures. Aiming at the lack of survivability research towards physical sensor node failure in the virtualized sensor network, the SVNE problem is mathematically modeled as a mixed integer programming problem considering resource constraints. A heuristic algorithm-node reliability-aware backup survivable embedding algorithm (NCS)-is further put forward to solve this problem. Firstly, a node reliability-aware embedding method is presented for initial embedding. The resource reliability of underlying physical sensor nodes is evaluated and the nodes with higher reliability are selected as mapping nodes. Secondly, a fault recovery mechanism based on resource reservation is proposed. The critical virtual sensor nodes are recognized and their embedded physical sensor nodes are further backed up. When the virtual sensor network (VSN) fails caused by the failure physical node, the operation of the VSN is restored by backup switching. Finally, the experimental results show that the strategy put forward in this paper can effectively guarantee the survivability of the VSN, reduce the failure penalty caused by the physical sensor nodes failure, and improve the long-term operating income of infrastructure provider.
随着无线传感器网络（WSN）的广泛应用，WSN虚拟化技术受到了广泛关注。WSN虚拟化中的一个关键挑战是可生存虚拟网络嵌入（SVNE）问题，该问题要在考虑底层可能出现故障的情况下，将虚拟网络高效地映射到WSN上。针对虚拟化传感器网络中缺乏对物理传感器节点故障的可生存性研究，将SVNE问题数学建模为一个考虑资源约束的混合整数规划问题。进一步提出了一种启发式算法——节点可靠性感知备份可生存嵌入算法（NCS）来解决此问题。首先，提出了一种用于初始嵌入的节点可靠性感知嵌入方法。评估底层物理传感器节点的资源可靠性，并选择可靠性较高的节点作为映射节点。其次，提出了一种基于资源预留的故障恢复机制。识别关键虚拟传感器节点，并对其嵌入的物理传感器节点进行进一步备份。当虚拟传感器网络（VSN）因物理节点故障而失效时，通过备份切换恢复VSN的运行。最后，实验结果表明，本文提出的策略能够有效保证VSN的可生存性，降低物理传感器节点故障造成的故障惩罚，并提高基础设施提供商的长期运营收益。
