23,558 research outputs found
AMCTD: Adaptive Mobility of Courier nodes in Threshold-optimized DBR Protocol for Underwater Wireless Sensor Networks
In dense underwater sensor networks (UWSN), the major confronts are high
error probability, incessant variation in topology of sensor nodes, and much
energy consumption for data transmission. However, there are some remarkable
applications of UWSN such as management of seabed and oil reservoirs,
exploration of deep sea situation and prevention of aqueous disasters. In order
to accomplish these applications, ignorance of the limitations of acoustic
communications such as high delay and low bandwidth is not feasible. In this
paper, we propose Adaptive mobility of Courier nodes in Threshold-optimized
Depth-based routing (AMCTD), exploring the proficient amendments in depth
threshold and implementing the optimal weight function to achieve longer
network lifetime. We segregate our scheme in 3 major phases of weight updating,
depth threshold variation and adaptive mobility of courier nodes. During data
forwarding, we provide the framework for alterations in threshold to cope with
the sparse condition of network. We ultimately perform detailed simulations to
scrutinize the performance of our proposed scheme and its comparison with other
two notable routing protocols in term of network lifetime and other essential
parameters. The simulations results verify that our scheme performs better than
the other techniques and near to optimal in the field of UWSN.Comment: 8th International Conference on Broadband and Wireless Computing,
Communication and Applications (BWCCA'13), Compiegne, Franc
Analysis of adaptive algorithms for an integrated communication network
Techniques were examined that trade communication bandwidth for decreased transmission delays. When the network is lightly used, these schemes attempt to use additional network resources to decrease communication delays. As the network utilization rises, the schemes degrade gracefully, still providing service but with minimal use of the network. Because the schemes use a combination of circuit and packet switching, they should respond to variations in the types and amounts of network traffic. Also, a combination of circuit and packet switching to support the widely varying traffic demands imposed on an integrated network was investigated. The packet switched component is best suited to bursty traffic where some delays in delivery are acceptable. The circuit switched component is reserved for traffic that must meet real time constraints. Selected packet routing algorithms that might be used in an integrated network were simulated. An integrated traffic places widely varying workload demands on a network. Adaptive algorithms were identified, ones that respond to both the transient and evolutionary changes that arise in integrated networks. A new algorithm was developed, hybrid weighted routing, that adapts to workload changes
A Cross-Layer Approach for Minimizing Interference and Latency of Medium Access in Wireless Sensor Networks
In low power wireless sensor networks, MAC protocols usually employ periodic
sleep/wake schedule to reduce idle listening time. Even though this mechanism
is simple and efficient, it results in high end-to-end latency and low
throughput. On the other hand, the previously proposed CSMA/CA-based MAC
protocols have tried to reduce inter-node interference at the cost of increased
latency and lower network capacity. In this paper we propose IAMAC, a CSMA/CA
sleep/wake MAC protocol that minimizes inter-node interference, while also
reduces per-hop delay through cross-layer interactions with the network layer.
Furthermore, we show that IAMAC can be integrated into the SP architecture to
perform its inter-layer interactions. Through simulation, we have extensively
evaluated the performance of IAMAC in terms of different performance metrics.
Simulation results confirm that IAMAC reduces energy consumption per node and
leads to higher network lifetime compared to S-MAC and Adaptive S-MAC, while it
also provides lower latency than S-MAC. Throughout our evaluations we have
considered IAMAC in conjunction with two error recovery methods, i.e., ARQ and
Seda. It is shown that using Seda as the error recovery mechanism of IAMAC
results in higher throughput and lifetime compared to ARQ.Comment: 17 pages, 16 figure
Advances in optimal routing through computer networks
The optimal routing problem is defined. Progress in solving the problem during the previous decade is reviewed, with special emphasis on technical developments made during the last few years. The relationships between the routing, the throughput, and the switching technology used are discussed and their future trends are reviewed. Economic aspects are also briefly considered. Modern technical approaches for handling the routing problems and, more generally, the flow control problems are reviewed
Pervasive intelligent routing in content centric delay tolerant networks
This paper introduces a Swarm-Intelligence based Routing protocol (SIR) that aims to efficiently route information in content centric Delay Tolerant Networks (CCDTN) also dubbed pocket switched networks. First, this paper formalizes the notion of optimal path in CCDTN and introduces an original and efficient algorithm to process these paths in dynamic graphs. The properties and some invariant features of these optimal paths are analyzed and derived from several real traces. Then, this paper shows how optimal path in CCDTN can be found and used from a fully distributed swarm-intelligence based approach of which the global intelligent behavior (i.e. shortest path discovery and use) emerges from simple peer to peer interactions applied during opportunistic contacts. This leads to the definition of the SIR routing protocol of which the consistency, efficiency and performances are demonstrated from intensive representative simulations
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