Wireless sensor networks (WSN) often operates unattended in harsh and inhospitable environments. While such deployment eliminates/reduces human intervention and provided fully-automated data gathering systems, WSNs are prone to sensors failure which not only can degrade the quality of coverage but also disrupt the data traffic. To address such a problem, most approaches in the literature deploy redundant nodes during network setup and reconfigure the network topology to establish alternate data paths. However, sometimes the network suffers a loss of a critical node or a large scale damage that involves many nodes and would thus create multiple disjoint partitions. For these cases, a provisioned approach for tolerating occasional failures at the network design level will not be effective. This talk analyzes the effect of a node failure on connectivity and explores the different recovery options. A number of schemes for connectivity restoration will be described. A summary of on-going efforts and open research problems will be also presented.
 

 
Mohamed F. Younis is currently an Associate professor in the department of computer science and electrical engineering at the university of Maryland Baltimore County (UMBC). Before joining UMBC, he was with the Advanced Systems Technology Group, an Aerospace Electronic Systems R&D organization of Honeywell International Inc. While at Honeywell he led multiple projects for building integrated fault tolerant avionics, in which a novel architecture and an operating system were developed. This new technology has been incorporated by Honeywell in multiple products and has received worldwide recognition by both the research and the engineering communities. He also participated in the development the Redundancy Management System, which is a key component of the Vehicle and Mission Computer for NASA’s X-33 space launch vehicle. Dr. Younis’ technical interest includes network architectures and protocols, wireless sensor networks, embedded systems, fault tolerant computing and distributed real-time systems. Dr. Younis has five granted and two pending patents. He is the chair of LCN’10 and program co-chair of the LCN’09, the ad-hoc and sensor networks symposium of ICC’09 and the wireless networks symposium of ICC’11. In addition, he serves/served on the editorial board of multiple journals and the organizing and technical program committee of numerous conferences.  Dr. Younis has published over 120 technical papers in refereed conferences and journals.