As wireless communication gains popularity, significant research has been devoted to supporting real-time transmission with stringent Quality of Service (QoS) requirements for wireless applications. At the same time, ...
详细信息
As wireless communication gains popularity, significant research has been devoted to supporting real-time transmission with stringent Quality of Service (QoS) requirements for wireless applications. At the same time, a wireless hybrid network that integrates a mobile wireless ad hoc network (MANET) and a wireless infrastructure network has been proven to be a better alternative for the next generation wireless networks. By directly adopting resource reservation-based QoS routing for MANETs, hybrids networks inherit invalid reservation and race condition problems in MANETs. How to guarantee the QoS in hybrid networks remains an open problem. In this paper, we propose a QoS-Oriented Distributed routing protocol (QOD) to enhance the QoS support capability of hybrid networks. Taking advantage of fewer transmission hops and anycast transmission features of the hybrid networks, QOD transforms the packet routing problem to a resource scheduling problem. QOD incorporates five algorithms: 1) a QoS-guaranteed neighbor selection algorithm to meet the transmission delay requirement, 2) a distributed packet scheduling algorithm to further reduce transmission delay, 3) a mobility-based segment resizing algorithm that adaptively adjusts segment size according to node mobility in order to reduce transmission time, 4) a traffic redundant elimination algorithm to increase the transmission throughput, and 5) a data redundancy elimination-based transmission algorithm to eliminate the redundant data to further improve the transmission QoS. Analytical and simulation results based on the random way-point model and the real human mobility model show that QOD can provide high QoS performance in terms of overhead, transmission delay, mobility-resilience, and scalability.
Energy efficiency is an important target for the management of wavelength-division-multiplexing-based core optical networks. A possible power management strategy for energy-efficient optical networks consists in putti...
详细信息
Energy efficiency is an important target for the management of wavelength-division-multiplexing-based core optical networks. A possible power management strategy for energy-efficient optical networks consists in putting opto-electronic devices (transponders and regenerators) into a low power mode, called sleep or idle, or even turning them off, during low traffic periods. It has been shown that sleep-mode enabled transponders and regenerators yield to substantial energy savings;however, their nonnegligible wake-up time may degrade the network performance in terms of the blocking probability of the connections. Opaque networks, in which transponders are utilized at each node in the end-to-end path, are especially prone to such degradations since multiple network nodes may simultaneously exhaust their pool of transponders due to long wake-up times, increasing the blocking probability. On the other hand, these degradations are less severe in transparent networks. In this paper, we evaluate how the duration of the wake-up time affects the performance of the network in terms of blocking probability depending on its architecture (transparent, translucent, or opaque) and the dynamicity of the traffic. Additionally, we propose a novel routing algorithm to mitigate the blocking probability due to the wake-up time. The benefits of the proposed algorithm are highlighted through extensive results.
Data loss due to integrity attacks or malfunction constitutes a principal concern in wireless sensor networks (WSNs). The present paper introduces a novel data loss/modification detection and recovery scheme in this c...
详细信息
Data loss due to integrity attacks or malfunction constitutes a principal concern in wireless sensor networks (WSNs). The present paper introduces a novel data loss/modification detection and recovery scheme in this context. Both elements, detection and data recovery, rely on a multivariate statistical analysis approach that exploits spatial density, a common feature in network environments such as WSNs. To evaluate the proposal, we consider WSN scenarios based on temperature sensors, both simulated and real. Furthermore, we consider three different routing algorithms, showing the strong interplay among (a) the routing strategy, (b) the negative effect of data loss on the network performance, and (c) the data recovering capability of the approach. We also introduce a novel data arrangement method to exploit the spatial correlation among the sensors in a more efficient manner. In this data arrangement, we only consider the nearest nodes to a given affected sensor, improving the data recovery performance up to 99%. According to the results, the proposed mechanisms based on multivariate techniques improve the robustness of WSNs against data loss.
Whenever new routing algorithms are proposed, corresponding performance gains are reported. Are these gains the same for different interconnect scenarios? Do the proposed techniques always outperform the previous ones...
详细信息
ISBN:
(纸本)9781424481552
Whenever new routing algorithms are proposed, corresponding performance gains are reported. Are these gains the same for different interconnect scenarios? Do the proposed techniques always outperform the previous ones in all possible routing scopes? We found out that the answer for these questions is no. In this work we evaluate several routing algorithms under an extensive set of experiments and different interconnect scenarios. The results show that different algorithms are preferable according to the different routing scopes, process generations and net sizes.
Providing better communication and maximising the communication performance in a Underwater Wireless Sensor Network (UWSN) is always challenging due to the volatile characteristics of the underwater environment. Radio...
详细信息
Providing better communication and maximising the communication performance in a Underwater Wireless Sensor Network (UWSN) is always challenging due to the volatile characteristics of the underwater environment. Radio signals cannot properly propagate underwater, so there is a need for acoustic technology that can support better data rates and reliable underwater wireless communications. Node mobility, 3-D spaces and horizontal communication links are some critical challenges to the researcher in designing new routing protocols for UWSNs. In this paper, we have proposed a novel routing protocol called Layer by layer Angle-Based Flooding (L2-ABF) to address the issues of continuous node movements, end-to-end delays and energy consumption. In L2-ABF, every node can calculate its flooding angle to forward data packets toward the sinks without using any explicit configuration or location information. The simulation results show that L2-ABF has some advantages over some existing flooding-based techniques and also can easily manage quick routing changes where node movements are frequent.
Mobile charge problem describes a fleet of mobile chargers delivers energy to the sensor nodes periodically in wireless sensor networks (WSNs). In it, every sensor node has an asynchronous rest working time during a c...
详细信息
Mobile charge problem describes a fleet of mobile chargers delivers energy to the sensor nodes periodically in wireless sensor networks (WSNs). In it, every sensor node has an asynchronous rest working time during a charging round. We consider the asynchronous rest working time and give the lower and upper bounds of the recharging cycle by the suitable total serving rate, to give the definition of time windows for the sensor nodes. In this paper, we model this problem in 2-dimensional WSNs as a vehicle routing problem with time windows (VRPTW). For solving the problem of multiple mobile chargers with different routing paths, we propose to transform the multiple routing problems into a single routing problem, by duplicating the sink into multiple virtual sinks. To optimize the routing path, we propose a local optimization algorithm by considering the collaborative charging among the mobile chargers. Through the simulations, we compare our proposed algorithm with the H eta ClusterCharging(beta) algorithm. We demonstrate the advantages of our collaborative scheduling algorithm in this problem.
With the rapid development of underwater acoustic modem technology, underwater acoustic sensor networks (UWASNs) have more applications in long-term monitoring of the deployment area. In the underwater environment, th...
详细信息
With the rapid development of underwater acoustic modem technology, underwater acoustic sensor networks (UWASNs) have more applications in long-term monitoring of the deployment area. In the underwater environment, the sensors are costly with limited energy. And acoustic communication medium poses new challenges, including high path loss, low bandwidth, and high energy consumption. Therefore, designing transmission mechanism to decrease energy consumption and to optimize the lifetime of UWASN becomes a significant task. This paper proposes a balance transmission mechanism, and divides the data transmission process into two phases. In the routing set-up phase, an efficient routing algorithm based on the optimum transmission distance is present to optimize the energy consumption of the UWASN. And then, a data balance transmission algorithm is introduced in the stable data transmission phase. The algorithm determines one-hop or multihop data transmission of the node to underwater sink according to the current energy level of adjacent nodes. Furthermore, detailed theoretical analysis evaluates the optimum energy levels in the UWASNs with different scales. The simulation results prove the efficiency of the BTM.
routing algorithm with more flexibility and fewer virtual channels is essential for high performance multicomputer systems. For three-dimensional mesh-connected networks, the traditional planar-adaptive routing algori...
详细信息
routing algorithm with more flexibility and fewer virtual channels is essential for high performance multicomputer systems. For three-dimensional mesh-connected networks, the traditional planar-adaptive routing algorithm requires three virtual channels to provide two-dimensional adaptivity. In this paper, a partially three-dimensional-adaptive routing algorithm is proposed for mesh-connected networks. The proposed algorithm utilizes at most two virtual channels for adaptive routing. Flit-level simulations are conducted to compare the proposed algorithm and two existing solutions. The simulation result shows that the proposed algorithm is superior to existing ones for nonuniform traffic patterns and apparently reduces the average packet latency.
Due to the opportunistic network with the characteristics of link frequent fracture and limited node capability, people maximize the efficiency of data transmission by getting the history information of node, using th...
详细信息
For sparse sensor networks, through our quantitative analysis, a routing algorithm based on node information and node mobility, called NINMR, is proposed in this paper. By building a simple analytical model, we analyz...
详细信息
暂无评论