The Construction of a Virtual Backbone with a Bounded Diameter in a Wireless Network

We usually use a digraph to represent a wireless network (WN). Correspondingly, a connected dominating set (CDS) of the digraph is usually used to denote a virtual backbone (VB) of the corresponding WN. In this article, focusing on the problem of a minimum strongly connected dominating and absorbing set (MSCDAS) with a bounded diameter (or guaranteed routing cost) for a digraph, which is strongly connected, we introduce two algorithms. One is called the guaranteed routing cost strongly connected dominating and absorbing set (GOC-SCDAS), which can generate a strongly connected dominating and absorbing set (SCDAS) with a performance ratio 14.4k+1/22 in respect of the optimal solution. Another is called the α guaranteed routing cost strongly connected bidirectional dominating and absorbing set (α-GOC-SCBDAS), which can generate a strongly connected bidirectional dominating and absorbing set (SCBDAS) with a performance ratio 8.8443k+1/22k+1/22 in respect of the optimal solution and a better routing cost, where k=rmax/rmin and rmin,rmax is the transmission range of nodes in the network. Through the simulation experiments, we obtain the conclusion that in terms of the diameter and average routing path length (ARPL) of CDS, the outputs of our algorithms are better than those of the algorithm in (Du et al. 2006).

Wireless Sensor Networks Fault-Tolerance Based on Graph Domination with Parallel Scatter Search

In wireless sensor/ad hoc networks, all wireless nodes frequently flood the network channel by transmitting control messages causing “broadcast storm problem”. Thus, inspired by the physical backbone in wired networks, a Virtual Backbone (VB) in wireless sensor/ad hoc networks can help achieve efficient broadcasting. A well-known and well-researched approach for constructing virtual backbone is solving the Connected Dominating Set (CDS) problem. Furthermore, minimizing the size of the CDS is a significant research issue. We propose a new parallel scatter search algorithm with elite and featured cores for constructing a wireless sensor/ad hoc network virtual backbones based on finding minimum connected dominating sets of wireless nodes. Also, we addressed the problem of VB node/nodes failure by either deploying a previously computed VBs provided by the main pSSEF algorithm that does not contain the failed node/nodes, or by using our proposed FT-pSSEF algorithm repairing the broken VBs. Finally, as nodes in a VB incur extra load of communication and computation, this leads to faster power consumption compared to other nodes in the network. Consequently, we propose the virtual backbone scheduling algorithm SC-pSSEF which aims to find multiple VBs using the VBs provided by the pSSEF algorithm and switch between them periodically to prolong the network life time.

New Computation of Resolving Connected Dominating Sets in Weighted Networks

In this paper we focus on the issue related to finding the resolving connected dominating sets (RCDSs) of a graph, denoted by G. The connected dominating set (CDS) is a connected subset of vertices of G selected to guarantee that all vertices in the graph are connected to vertices in the CDS. The connected dominating set with minimum cardinality, or minimum CDS (MCDS), is an adequate virtual backbone for information interchange in a network. When distinct vertices of G have also distinct representations with respect to a subset of vertices in the MCDS, it is said that the MCDS includes a resolving set (RS) of G. With this work, we explore different strategies to find the RCDS with minimum cardinality in complex networks where the vertices have different importances.

Energy Measure Semigraph-Based Connected Edge Domination Routing Algorithm in Wireless Sensor Networks

In wireless sensor networks (WSNs), batteries are used as power source which is limited, and replacement of the battery is difficult. Since communication between nodes consumes most of the node power, topology-based power control is essential for reducing energy consumption. It is necessary to use optimized topology-based energy control model, so the selected nodes are used to generate a virtual backbone, which reduces unwanted routing of data. The virtual backbone for optimized topology can be created by connected dominating set (CDS) of graph theory. However, generating the virtual backbone by using the CDS algorithm is an NP-hard problem because of larger network size. To overcome this problem, in this paper, a novel distributed connected edge dominating set-based semigraph model (S-CEDS) is proposed. The performance ratio of the proposed S-CEDS is measured as (4 + ln∆′) |opt|, where |opt| represents the network size. The proposed S-CEDS is implemented using the ns-2 simulator and evaluated with conventional routing protocols such as AODV and DSDV. The results show that the proposed S-CEDS approach increases throughput and network lifetime. Also, it reduces energy consumption and average number of hops required for data transmission.

CONSTRUCTION OF MINIMUM CONNECTED DOMINATING SET IN A GRAPH AND ITS APPLICATION IN WIRELESS SENSOR NETWORKS

It is largely applied in Wireless Sensor Networks (WSN). It acts as a virtual backbone in WSNs.algorithms of finding such minimum connected dominating set was studied. A new algorithm for constructing a routing in WSN using one of the algorithms is proposed and implemented using java language. The sampleoutputs are also included

A Reconfigurable Multicast Routing Protocol for Mobile Ad-Hoc Networks

An infrastructure independent and self-organizing network where the mobile nodes are communicated with each other through wireless links is referred asMobile ad-hoc network. Amajor challenging task of mobile ad-hoc networks is Route maintenance due to some reasons such as frequent topological changes, packet collisions and bad channels which may cause some link breakages. Reconfigurable Virtual Backbone (RVB) construction and maintenance play a vital role, mainly in the multicast routing of mobile ad-hoc networks (MANETs). In this paper, the issues in providing a reconfigurable virtual backbone with the lower overhead are investigated and here we come up with a solution and propose a Reconfigurable Multicast Routing Protocol (RMRP) for constructing a virtual backbone and generating an alternate path during link failures. In comparison with the existing backbone and link recovery protocols like Backbone Group Model (BGM), Hierarchical Virtual Backbone Construction (HVBC) protocol and Local Link Failure Recovery (LLFR) protocol, the proposed protocol yields effective results in constructing a reconfigurable virtual backbone and generating an on-demand alternate path with the minimized overhead, increasing packet delivery ratio, throughput, minimizing delay of transmission, energy consumption, and with the improved routing performance significantly.