A novel optimization-based bandwidth-aware minimum power multicast routing algorithm in green wireless networks

An Efficient Backbone Based Quick Link Failure Recovery Multicast Routing Protocol

Minimizing energy consumption by joint radio and computing resource allocation in Cloud-RAN

Wireless mesh network (WMN) is a peculiar type of growing technology that can alter the world more effectively in the coming decades. Multicast routing in mesh networks is the distribution of data from a single source to multiple destinations or multiple sources to multiple destinations through the intermediate nodes. There can be many numbers of intermediate nodes between source and destination. But the number of hops a packet traverses decides the energy consumed, data rate, speed, throughput and other characteristics of a network. The reduction in the number of hops leads to reduced processing of data which leads to reduced consumption of power. In this paper, energy coherence for wireless mesh networks from a point of view that started recently to attract the attention of the conservation of energy for operational and the environment reasons which is known as the Green Networking is considered. This paper discusses the energy coherence of multicast routing algorithm based on angle which reduces the hop count leading to reduction in energy consumption and the angle with efficient energy optimization is found. Not only the energy, other network parameters like throughput, delay, packet delivery ratio, packet loss ratio have also been improved at the appropriate angle. This in turn enhances the QoS of the network.

In wireless networks, the multicast QoS routing is a key technique to increase bandwidth utilization, but the multicast routing is typically complicated and difficult because it belongs to the NP-complete problem. The main goal of a delay-bounded wireless multicast algorithm is to determine the optimal multicast tree that has the least cost while satisfying the delay-bounded requirement. However, previous studies suffer from the Tree setup-break and dangling node problems, and yield a large number of control messages. This paper thus proposes the adaptive distributed multicast routing (ADMR) algorithm to guarantee cycle-free, and to overcome these two problems while yielding the least-cost delay-bounded multicast tree for high-density member multicast networks. Numerical results indicate that ADMR significantly outperforms the Jia-based algorithms in number of control messages and setup convergent time.

Anypath routing is proposed to improve the performance of wireless networks by exploiting the spatial diversity and broadcast nature of the wireless medium. In this paper, we study anypath routing in wireless networks with directional antennas, and propose DART (Directional Anypath RouTing), a crosslayer design of MAC and routing layers. For the routing layer, we propose two shortest directional anypath routing algorithms based on two antenna models. Our routing algorithms are simple and fast, thus are suitable for implementation in practical protocols. For the MAC layer, we present a directional anycast MAC, which is an enhancement to the IEEE 802.11 MAC, making DART suitable for integration into current systems. Simulation results show that DART can significantly reduce the packet transmission delay.

Energy saving and high delivery reliability are two essential metrics in wireless ad hoc networks. In this paper, we propose a joint power control and network coding (PCNC) scheme which regulates the transmission power to reduce the overall energy usage and uses network coding to improve reliability by reducing the number of packet retransmissions. To argue for PCNC scheme, we investigate both unicast and multicast routing scenarios. To evaluate routing optimality, we adopt expected utility as a metric, which integrates energy cost, reliability, and benefit value. Based on the expected utility, we explore the optimality in both unicast and multicast routing. For unicast routing, we propose an optimal algorithm. We show the NP-hardness of multicast routing problem, and also design a heuristic solution. Results from simulations demonstrate that PCNC improves the performance in terms of expected utility compared with existing techniques.

Efficient multicasting over Wireless Mesh Network (WMN) is challenging due to dynamic and multi-hop wireless communication among multicast group members. Multicast Ad hoc On-Demand Distance Vector (MAODV) protocol is a tree based multicast routing protocol that enables dynamic, self-starting, multi-hop routing between participating mobile nodes wishing to join or participate in a multicast group in Wireless Mesh Network (WMN). The mobility of mobile nodes often causes link breakage in the tree-based protocols which sometime results in tree partitioning and poor performance. In MAODV, when a broken link is detected between two nodes on the multicast tree, the node downstream to the break is responsible for initiating the repair of the broken link. After link repair, it is likely that the previous distance between the nodes (nodes downstream to the link breakage) and the group leader will not remain same. The shortest path from the group leader to the nodes downstream to the node which initiates link breakage is not ensured. Moreover, if the node attempting to repair a tree link break does not receive a response after certain attempts, it assumes that the multicast tree is not repairable currently and this leads to tree partitioning. In this paper, an improved link repair technique is proposed which ensures shortest path from any node to the group leader. Simulation results demonstrate significant improvement in performance metrics compared to standard MAODV.

Under given energy constraints, a fundamental problem in wireless networks is to maximize network lifetime and prolong network operational lifetime. Since nodes in the network can be affected with interference of peripheral nodes, it causes collisions and congestions. Thus, whole network consumes more energy. It is clear that the higher density of network the higher degree of nodes. It leads to more redundant coverage, i.e. more overlapped areas (joint areas between adjusted nodes) in the network, which also increases energy consumption and probability of collisions. This paper proposes an energy-efficient topology control algorithm. Based on location awareness, the proposed algorithm minimizes a set of the relay nodes keeping the connectivity and whole network coverage. To address this, the algorithm calculates density of network and divides the transmission range of a node into border area and core area. Then, the algorithm calculates overlapped areas between border nodes and selects relays amongst them. As a result, the network can be seen as a sparse network in which the overlapped areas are reduced. Since only selected nodes act as relays at the particular time interval, it helps to reduce whole network energy consumption, prolong operational network lifetime and reduce collisions or congestions. The results of simulation show that the proposed algorithm improves energy-efficiency of the network while preserving connectivity and functions of routing agent.

This paper investigates the issues of QoS multicast routing in wireless ad hoc networks. Due to limited bandwidth of wireless nodes, a QoS multicast call will be blocked if there does not exist a single multicast tree that has the requested bandwidth, even though there is enough bandwidth in the system to support the call. We propose a new QoS multicast routing scheme that uses multiple trees. The aggregate bandwidth of multiple trees can meet the bandwidth requirement and the delay from the source to the farthest destination node shall not exceed a pre-specified bound. Two strategies for constructing multiple trees are studied. The simulation results show that the new scheme significantly improves the request success rate and makes a better use of network resources.KeywordsDestination NodeNetwork LoadSuccess RatioBandwidth RequirementMulticast TreeThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Recently, importance of wireless networks increased significantly. Wireless Mesh Networks (WMNs) are receiving growing attention and offer many advantages in terms of connectivity and reliability. Multicast communication is an important technology for wireless networks in which the same content of data should be delivered to a group of receiver nodes simultaneously. So multicast routing provides efficient data distribution among a group of nodes rather than other traditional unicast routing strategies. Here we focus on the Channel Allocation (CA) scheme which efficiently utilizes multiple wireless interfaces to achieve better throughput and improving the radio interference. This kind of problem has been proved to be NP-hard. Hence, solving the multicast channel assignment problem in MCMR WMNs will be more complicated than that of traditional networks. The research in this paper is aimed at improving the network performance for efficient joint channel assignment and multicast routing problem in MCMR WMNs by using the Q-learning scheme. We also implement our proposed channel assignment algorithm, and evaluate and compare its performance with LAMR. Simulations and experimental results demonstrate that QLMR outperforms the previous works in terms of achieved average throughput, average end-to-end delay, average packet delivery ratio and so on. We will evaluate the performance of the proposed scheme.

In this paper, we study the multicast routing problem in wireless relay networks. Our objective is to maximize the number of recipients of a multicast stream by deciding the topology of the wireless relay network based on the given resource budget and the channel quality of the nodes. To the best of our knowledge, this important maximization problem has not been previously addressed. Since existing approaches cannot effectively solve the problem, we propose a scheme called multicast subscriber selection (MSS). Through analysis, we prove that the path-construction problem is NP-hard. Our heuristic MSS has polynomial-time complexity, and its performance is bound to the optimal solution. We also evaluate the performance of MSS via simulations. The results demonstrate that the existing unicast routing approach is inefficient under different budgets and channel conditions. In contrast, the proposed MSS scheme achieves better performance, because it can effectively utilize relay stations.

Fractional Link scheduling is one of the most fundamental problems in wireless networks. The prevailing approach for shortest fractional link scheduling is based on a reduction to the maximum-weighted independent set problem, which itself may not admit efficient approximation algorithms. In addition, except for the wireless networks under the protocol interference model, none of the existing scheduling algorithms can produce a link schedule with explicit upper bounds on its length in terms of the link demands. As the result, the polynomial approximate capacity regions in these networks remain blank. This paper develops a purely combinatorial paradigm for fractional link scheduling in wireless networks. In addition to the superior efficiency, it is able to provide explicit upper bounds on the lengths of the produced link schedule. By exploiting these upper bounds, polynomial approximate capacity regions are derived. The effectiveness of this new paradigm is demonstrated by its applications in wireless networks under the physical interference model and wireless MIMO networks under the protocol interference model.

In this paper, we propose to address the energy efficient routing problem in multi-hop wireless networks with accumulative relay. In the accumulative relay model, partially overheard signals of previous transmissions for the same packet are used to decode it using a maximal ratio combiner technique [J.G. Proakis, 2001]. Therefore, additional energy saving can be achieved over traditional energy efficient routing. The idea of accumulative relay originates from the study of relay channel in information theory with a main focus on network capacity. It has been independently applied to minimum-energy broadcasting in L.G. Manish Agrawal et al. (2004), I. Maric and R. Yates (2002). We formulate the minimum energy accumulative routing problem (MEAR) and study it. We obtain hardness of approximation results counterbalanced with good heuristic solutions which we validate using simulations. Without energy accumulation, the classic shortest path (SP) algorithm finds the minimum energy path for a source-destination pair. However, we show that with energy accumulation, the SP can be arbitrarily bad. We turn our attention to heuristics and show that any optimal solution of MEAR can be converted to a canonical form - wave path. Armed with this insight, we develop a polynomial time heuristic to efficiently search over the space of all wavepaths. Simulation results show that our heuristic can provide more than 30% energy saving over minimum energy routing without accumulative relay. We also discuss the implementation issues of such a scheme.

The Unmanned Aerial Vehicles (UAVs), commonly known as drones, are significant in the agriculture sphere to automate the work such as: data acquisition, crop spraying among others. This paper proposes a path planning solution for a team of UAVs that is required to whiten a greenhouse’s roof, this problem having both social-economic impact, as well as scientific-technical impact. First, the space around the roof is partitioned into cells based on a 3D cell decomposition technique, labeling the cells including the surface of the roof as regions of interest (ROIs). Based on this representation, a Petri net (PN) model captures the motion of drones, while their trajectories are returned by a Mixed Integer Linear Programming (MILP) problem which optimizes the energy consumption. An adaptable strategy is used such that the MILP problem considers only the available UAVs with enough energy to reach the ROIs. The algorithm is implemented in MATLAB and the simulation results are captured in a video link, evaluating the impact of the size of the team and the precision used for mapping the environment over the running time.

Design of certification authority using secret redistribution and multicast routing in wireless mesh networks