One fundamental issue in cognitive radio mobile ad hoc networks (CR-MANETs) is the selection of a stable path between any source and destination node to reduce the end-to-end delay and energy consumption arisen from route reconstruction. In this way, we analyse the link stability by calculating the link life time that is dependent on failures caused by secondary users’ (SUs) movements and primary users’ (PUs) activities. We propose a joint stability-based routing, link scheduling and channel assignment (SRLC) algorithm in CR-MANETs, which is benefited from considering the link life time, amount of interference imposed on PUs and energy consumption. The proposed algorithm selects a frequency channel/time slot in a way that channel utilization and previous behaviours of SUs and PUs, are taken into account. In the proposed SRLC, the concept of load balancing is applied by avoiding to route packets through SUs with insufficient energy. The effectiveness of the proposed algorithm is verified by evaluating the aggregate interference energy, end-to-end delay, goodput and the energy usage per packet transmission under three different scenarios. The results show our proposed scheme finds better routes compared to the recently proposed joint stable routing and channel assignment protocol.
相似文献Mobile ad hoc network (MANET) is vulnerable to security attacks because of the shared radio medium and lack of centralized coordination. Since most multi-hop routing protocols implicitly assume cooperative routing and are not originally designed for security attacks, MANET has been challenged by diverse denial-of-service attacks that often interfere with the protocol and interrupt on-going communication. In this paper, we propose an explore-based active detection scheme, called EBAD, to efficiently mitigate the routing misbehaviors in MANETs running with dynamic source routing. The basic idea is that a source node broadcasts a route request packet with a fictitious destination node to lure potential malicious nodes to reply a fake route reply packet. If the source node receives the fake route reply packet or an intermediate node cannot decrypt the received route reply packet, the routing misbehavior can be detected. We also propose a route expiry timer based approach to reduce the effect of route cache pollution because of the fake route reply. We present a simple analytical model of the EBAD and its numerical result in terms of detection rate. We also conduct extensive simulation experiments using the OMNeT++ for performance evaluation and comparison with the existing schemes, CBDS and 2ACK. The simulation results show that the proposed countermeasure can not only improve the detection rate and packet delivery ratio but also can reduce the energy consumption and detection latency.
相似文献Mobile ad hoc network is open medium and infrastructure-less network. Mobile ad hoc network is susceptible to various security attacks such as, black hole attack, gray hole attack, bad mouthing attack, sybil attack and worm hole attack due to open medium, infrastructure-less features and lack of in-built security. In black hole attack and gray hole attack, attacker falsely sends route reply and dropped data packets received from source node. Due to these attacks, performance of mobile ad hoc network decreases. This paper proposes a time stamp-based algorithm which is an enhanced version of existing IDSNAODV algorithm. Proposed algorithm modifies existing palling process to validate identity of observer nodes using a time stamp-based approach. Based on defined set of rules and recorded activities report, source node decides the nature of target node. The performance of proposed algorithm is evaluated using the network simulator. The proposed algorithm shows improved performance for packet delivery ratio, throughput and routing overhead as compared to existing algorithm.
相似文献The idea of Smart City incorporates a few ideas being technology, economy, governance, people, management, and infrastructure. This implies a Smart City can have distinctive communication needs. Wireless technologies, for example, WiFi, Zig Bee, Bluetooth, WiMax, 4G or LTE have introduced themselves as a solution for the communication in Smart City activities. Nonetheless, as the majority of them utilize unlicensed interference, coexistence and bands issues are increasing. So to solve the problem IoT is used in smart cities. This paper addresses the issues of both resource allocation and routing to propose an energy efficient, congestion aware resource allocation and routing protocol (ECRR) for IoT network based on hybrid optimization techniques. The first contribution of proposed ECRR technique is to employ the data clustering and metaheuristic algorithm for allocate the large-scale devices and gateways of IoT to reduce the total congestion between them. The second contribution is to propose a queue based swarm optimization algorithm for select a better route for future route based on multiple constraints, which improves the route discovering mechanism. The proposed ECRR technique is implemented in Network Simulator (NS-2) tool and the simulation results are compared with the existing state-of-art techniques in terms of energy consumption, node lifetime, throughput, end-to-end delay, packet delivery ratio and packet overheads.
相似文献Extensive use of sensor and actuator networks in many real-life applications introduced several new performance metrics at the node and network level. Since wireless sensor nodes have significant battery constraints, therefore, energy efficiency, as well as network lifetime, are among the most significant performance metrics to measure the effectiveness of given network architecture. This work investigates the performance of an event-based data delivery model using a multipath routing scheme for a wireless sensor network with multiple sink nodes. This routing algorithm follows a sink initiated route discovery process with the location information of the source nodes already known to the sink nodes. It also considers communication link costs before making decisions for packet forwarding. Carried out simulation compares the network performance of a wireless sensor network with a single sink, dual sink, and multi sink networking approaches. Based on a series of simulation experiments, the lifetime aware multipath routing approach is found appropriate for increasing the lifetime of sensor nodes significantly when compared to other similar routing schemes. However, energy-efficient packet forwarding is a major concern of this work; other network performance metrics like delay, average packet latency, and packet delivery ratio are also taken into the account.
相似文献Delay tolerant networks can not maintain end-to-end connectivity. Thus the routing is one of the critical issues. As we known, the two-level community model including the small community and the big community is proposed for the first time. In the same small community, any two member nodes are friends with each other. And in the same big community which is constructed of some small communities, any two communities have some pairs of friend nodes between them. Based on this model, a two-level community-based routing (TLCR) algorithm is presented in delay tolerant networks. In TLCR, according to the location of packet holder including inside the small community of destination node, inside of the big community and outside of the small community of destination node, and outside of the big community of destination node, the different packet forwarding strategies are investigated. The number of relay nodes selected by a packet holder is decreasing with the holder’s location from inside of the small community of destination node to outside of the big community of destination node. The probability of the source node successfully delivers the packet to the destination node and the copies number corresponding with the above three locations are analyzed, respectively. The simulation results show that TLCR not only improves the delivery ratio but also greatly reduces the resource cost.
相似文献The vehicular delay-tolerant network is the real-life application based area of Delay tolerant network where communication takes place using vehicular nodes and roadside units. The topology used in vehicular networks is highly dynamic by architecture due to the use of moving vehicular nodes. It operates in such a scenario where a direct path between source and destination remains absent on the most piece of the time. In case of non-existence of connected path vehicular delay-tolerant network works opportunistically and uses the same store, carry, and forward paradigm as Delay Tolerant Network. However, the routing protocols designed for vehicular delay-tolerant network faces crucial challenges like inadequate relay node, incomplete data transfer, a large number of packet drop, and uncertain delivery time. In this research paper, we propose a novel routing strategy for the vehicular delay-tolerant network. The proposed routing strategy selects efficient vehicular relay node for complete packet transfer and intelligently reduces the packet drop for timely packet delivery. We implement the proposed routing strategy in the ONE simulator; the ONE simulator provides an opportunistic environment for nodes. We analyze the performance of the proposed strategy under various simulations results using different parameters. The results show that the proposed strategy outperforms standard routing protocols in terms of considered parameters and provide an efficient solution for the problem of disconnection.
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