An efficient QOS routing protocol for mobile ad-hoc networks

To satisfy the user requirements for continuous and real-time multimedia information, the concept of Quality of Service (QoS) has emerged as a main issue in mobile ad-hoc networks. QoS routing is to find a route according to the QoS requirements of the users. In this paper, we propose an efficient QoS routing protocol that is based on AODV over TDMA, one of the typical routing protocols for mobile ad-hoc networks, by making a bandwidth reservation for QoS guarantee. While the existing schemes calculate the maximum available bandwidth for each candidate path, our scheme is to check only if the bandwidth of a given path satisfies the end-to-end QoS requirement. Also, the key idea in the bandwidth reservation is to select carefully time slots without causing any conficts in the wireless environment, thereby maximizing the bandwidth efficiency. In order to evaluate the performance of the proposed QoS routing protocol, some simulations are carried out in the adhoc environment. The simulation results show that the proposed protocol provides sufficiently low and stable delay performance regardless of the offered load.1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI

Design of an energy-efficient geographic routing protocol for mobile ad-hoc networks

Mobile Ad-hoc networks extend communications beyond the limit of infrastructure based networks. Future wireless applications will take advantage of rapidly deployable, self-configuring multi-hop mobile Ad-hoc networks. In order to provide robust performance in mobile Ad-hoc networks and hence cope with dynamic path loss conditions, it is apparent that research and development of energy efficient geographic routing protocols is of great importance. Therefore various mobile Ad-hoc routing protocols have been studied for their different approaches. Forwarding strategies for geographic routing protocols are discussed and there is a particular focus on the pass loss model used by those routing protocols, the restriction and disadvantage of using such path loss model is then discussed. A novel geographic routing protocol which incorporates both the link quality and relay node location information has been developed to determine an energy efficient route from source to destination. The concepts of a gain region and a relay region to minimize the energy consumption have been proposed to define the area in where the candidate relay nodes will be selected with the minimized hop count. The signalling overhead required by the protocol has been analyzed in various scenarios with different traffic load, node densities and network sizes. Discrete event simulation models are therefore developed to capture the behaviour and characteristics of the operation of the developed routing protocol under different path loss conditions and network scenarios. A non-free space path loss model has been developed with a random loss between the nodes to simulate a realistic path loss scenario in the network. An enhanced signalling process has been designed in order to achieve advanced routing information exchange and assist routing determination. Comparison of simulated characteristics demonstrates the significant improvement of the new routing protocol because of its novel features, the gain region to ensure the deductiono f the energyc onsumptiont,h e relay region to ensuret he forward progress to the destination and hence maintain an optimised hop count. The simulation results showed that the energy consumption under the operation of the developed protocol is 30% of that with a conventionagl eographicarl outing protocol

An efficient QOS routing protocol for mobile ad-hoc networks

To satisfy the user requirements for continuous and real-time multimedia information, the concept of Quality of Service (QoS) has emerged as a main issue in mobile ad-hoc networks. QoS routing is to find a route according to the QoS requirements of the users. In this paper, we propose an efficient QoS routing protocol that is based on AODV over TDMA, one of the typical routing protocols for mobile ad-hoc networks, by making a bandwidth reservation for QoS guarantee. While the existing schemes calculate the maximum available bandwidth for each candidate path, our scheme is to check only if the bandwidth of a given path satisfies the end-to-end QoS requirement. Also, the key idea in the bandwidth reservation is to select carefully time slots without causing any conficts in the wireless environment, thereby maximizing the bandwidth efficiency. In order to evaluate the performance of the proposed QoS routing protocol, some simulations are carried out in the adhoc environment. The simulation results show that the proposed protocol provides sufficiently low and stable delay performance regardless of the offered load.1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI

Trust Based Routing to Improve Network Lifetime of Mobile Ad Hoc Networks

Mobile Ad hoc Network is an impromptu wireless network consisting of mobile, self governing independent nodes. Routing in Mobile Ad hoc Networks has been a major concern due to its dynamic topology, lossy and unreliable links. In traditional routing, a single specific node is selected in prior as the potential next-hop forwarder for a packet. Unlike traditional routing, a category of routing technique termed Opportunistic Routing exploits the broadcast nature of wireless medium to compensate the unreliability of the packet transmissions in the channel. In Opportunistic Routing, one among the set of candidate nodes is selected as the potential next-hop forwarder using metrics like number of transmissions in a link, link error probability, cost, etc., for packet transmission. For selection and prioritization of candidates that ensures minimum number of transmissions from source to destination node, whilst improving the lifetime of the network on determining the residual battery energy, a new metric is proposed. This metric helps in improving the network lifetime considering the transmission powers in terms of the fraction of residual battery powers. Further, as nodes in mobile ad hoc networks are susceptible to attacks, a trust model based on direct, as well as indirect trust degrees from similar trusted neighbours is integrated in order to overcome the vulnerability due to attacks by malicious/selfish nodes and to provide reliable packet transmissions. Fading of trust is incorporated with a perspective to ensure the uncertainty of trust with time until it is updated

Cross-layer Balanced and Reliable Opportunistic Routing Algorithm for Mobile Ad Hoc Networks

For improving the efficiency and the reliability of the opportunistic routing algorithm, in this paper, we propose the cross-layer and reliable opportunistic routing algorithm (CBRT) for Mobile Ad Hoc Networks, which introduces the improved efficiency fuzzy logic and humoral regulation inspired topology control into the opportunistic routing algorithm. In CBRT, the inputs of the fuzzy logic system are the relative variance (rv) of the metrics rather than the values of the metrics, which reduces the number of fuzzy rules dramatically. Moreover, the number of fuzzy rules does not increase when the number of inputs increases. For reducing the control cost, in CBRT, the node degree in the candidate relays set is a range rather than a constant number. The nodes are divided into different categories based on their node degree in the candidate relays set. The nodes adjust their transmission range based on which categories that they belong to. Additionally, for investigating the effection of the node mobility on routing performance, we propose a link lifetime prediction algorithm which takes both the moving speed and moving direction into account. In CBRT, the source node determines the relaying priorities of the relaying nodes based on their utilities. The relaying node which the utility is large will have high priority to relay the data packet. By these innovations, the network performance in CBRT is much better than that in ExOR, however, the computation complexity is not increased in CBRT.Comment: 14 pages, 17 figures, 31 formulas, IEEE Sensors Journal, 201

Trust based algorithm for candidate node selection in hybrid MANET-DTN

The hybrid MANET - DTN is a mobile network that enables transport of the data between groups of the disconnected mobile nodes. The network provides benefits of the Mobile Ad-Hoc Networks (MANET) and Delay Tolerant Network (DTN). The main problem of the MANET occurs if the communication path is broken or disconnected for some short time period. On the other side, DTN allows sending data in the disconnected environment with respect to higher tolerance to delay. Hybrid MANET - DTN provides optimal solution for emergency situation in order to transport information. Moreover, the security is the critical factor because the data are transported by mobile devices. In this paper, we investigate the issue of secure candidate node selection for transportation of the data in a disconnected environment for hybrid MANET- DTN. To achieve the secure selection of the reliable mobile nodes, the trust algorithm is introduced. The algorithm enables select reliable nodes based on collecting routing information. This algorithm is implemented to the simulator OPNET modeler