On Computing Resilient Virtual Backbone in CRNs

Recently, the concept of virtual backbone (VB) has been investigated to improve the efficiency of wireless networks. Since node fault is the most significant failure type in various wireless networks, many efforts are made to improve the resilience of VB by increasing node connectivity. However, in cognitive radio networks (CRNs), communication disruption among unlicensed users (cognitive users, CUs) is likely due to the unpredictable channel unavailability caused by licensed users (primary users, PUs). As a result, the fault-tolerance of a VB in CRNs can be greatly improved by enhancing edge connectivity. This paper investigates how to generate a fault-tolerant VB with maximum lifetime in CRNs against unforeseen PU activities. We define this problem as the maximum lifetime sturdier virtual backbone (MLSVB) problem, and propose a heuristic algorithm for it. To the best of our knowledge, this is the first work to discuss about the requirements of fault-tolerant VB in CRNs.