A Kind of Improved RED Algorithm of WSN Oriented to Self-Similar Traffic

2011 ◽  
Vol 214 ◽  
pp. 549-553
Author(s):  
Yu Jiao Wang ◽  
Hai Yun Lin

Active queue management algorithm works at network routing node. It notifies terminal system control transmission rate in advance with discard or mark packet before buffer queue overflows, so as to avoid congestion. Aiming at characteristics of wireless sensor network (WSN) and based on introduction of traditional RED algorithm, the paper introduced H parameter to represent traffic similarity to original linear relationship between packet loss probability and average queue length to form the non-linear relationship related to self-similarity. Then a kind of improved RED algorithm of WSN oriented to self-similar traffic was proposed. The detail implementation flow was also provided. Simulation based on OPNET shows that the improved RED is superior to traditional RED algorithm in steady performance.

Author(s):  
Chao Wang

Background: It is important to improve the quality of service by using congestion detection technology to find the potential congestion as early as possible in wireless sensor network. Methods: So an improved congestion control scheme based on traffic assignment and reassignment algorithm is proposed for congestion avoidance, detection and mitigation. The congestion area of the network is detected by predicting and setting threshold. When the congestion occurs, sensor nodes can be recovery quickly from congestion by adopting reasonable method of traffic reassignment. And the method can ensure the data in the congestion areas can be transferred to noncongestion areas as soon as possible. Results: The simulation results indicate that the proposed scheme can reduce the number of loss packets, improve the throughput, stabilize the average transmission rate of source node and reduce the end-to-end delay. Conclusion: : So the proposed scheme can enhance the overall performance of the network. Keywords: wireless sensor network; congestion control; congestion detection; congestion mitigation; traffic assignment; traffic reassignment.


2016 ◽  
Vol 26 (1) ◽  
pp. 17
Author(s):  
Carlos Deyvinson Reges Bessa

ABSTRACTThis work aims to study which wireless sensor network routing protocol is more suitable for Smart Grids applications, through simulation of AODV protocols, AOMDV, DSDV and HTR in the NS2 simulation environment. Was simulated a network based on a residential area with 47 residences, with one node for each residence and one base station, located about 25m from the other nodes. Many parameters, such as packet loss, throughput, delay, jitter and energy consumption were tested.  The network was increased to 78 and 93 nodes in order to evaluate the behavior of the protocols in larger networks. The tests proved that the HTR is the routing protocol that has the best results in performance and second best in energy consumption. The DSDV had the worst performance according to the tests.Key words.- Smart grid, QoS analysis, Wireless sensor networks, Routing protocols.RESUMENEste trabajo tiene como objetivo estudiar el protocolo de enrutamiento de la red de sensores inalámbricos es más adecuado para aplicaciones de redes inteligentes, a través de la simulación de protocolos AODV, AOMDV, DSDV y HTR en el entorno de simulación NS2. Se simuló una red basada en una zona residencial con 47 residencias, con un nodo para cada residencia y una estación base, situada a unos 25 metros de los otros nodos. Muchos parámetros, tales como la pérdida de paquetes, rendimiento, retardo, jitter y el consumo de energía se probaron. La red se incrementó a 78 y 93 nodos con el fin de evaluar el comportamiento de los protocolos de redes más grandes. Las pruebas demostraron que el HTR es el protocolo de enrutamiento que tiene los mejores resultados en el rendimiento y el segundo mejor en el consumo de energía. El DSDV tuvo el peor desempeño de acuerdo a las pruebas.Palabras clave.- redes inteligentes, análisis de calidad de servicio, redes de sensores inalámbricas, protocolos de enrutamiento.


Author(s):  
Xiaoping Huang ◽  
Fangyi Wen ◽  
Zhongxin Wei

In recent years, with the development of communication technology, embedded computing technology and sensor technology, it has become increasingly mature. Micro sensors with sensing, computing and communication capabilities have appeared in large numbers and developed rapidly, making wireless sensor networks widely used. People put forward higher requirements for the accuracy, reliability and flexibility of the image acquisition system. The image transmission system using analog technology not only has low image quality, but also has a serious waste of system resources, is not easy to form a complex network structure, and has poor functional scalability. In view of the actual needs of the current image acquisition and wireless transmission system, based on embedded technology, image acquisition, processing technology and network transmission technology, this paper proposes and designs a low-cost, high-reliability embedded image acquisition and wireless transmission system. Experimental tests show that this system has reasonable design, high video coding efficiency, good image continuity, stable operation, and basically realizes the display, storage and playback functions of the collected video data. Improve the transmission rate of the system and reduce the distortion caused by compression in terms of image compression. At the same time, it supports multiple image resolutions, frame rate options and multiple video formats, and the system’s transmission rate can adapt to the state of the network. This design fulfills the basic requirements of an embedded image acquisition system based on network technology, and provides a good foundation for the next development of a gigabit network-based image acquisition system.


2021 ◽  
pp. 1-11
Author(s):  
Shu Zhang ◽  
Jianhua Chen

 This paper analyzes the security algorithm and energy cost of wireless sensor networks in depth, and designs and implements a series of energy-optimized security solutions to ensure the secure establishment and operation of wireless sensor networks. This paper proposes an improved Ad hoc network routing protocol based on energy control. It introduces a low-energy balanced routing algorithm to reduce routing transmission energy consumption, balance network traffic, and improve the energy control performance of network routing protocols. The protocol uses a cross-layer design in this way, the route selection combines the information of the link the remaining energy. A joint function is formed by the transmit power level remaining energy. The joint function of all nodes on the path is used as the basis for route selection and applied to the route discovery stage. At the same time, the protocol introduces edge degree parameters in the establishment process, the idea of minimum energy consumption path and the introduction of energy consumption ratio parameters in the cluster skull backbone network generation process are adopted to realize the energy optimization of the path establishment process. At the same time, the protocol uses the message interaction mechanism in the path establishment process to implement a node security authentication scheme based on secret shared information without adding any routing communication messages, which effectively prevents the passive and active attacks of the attacker on the network. The results of simulation experiments prove that the secure routing protocol achieves the network’s balanced energy consumption while ensuring the secure communication of the network, and solves the energy problem.


Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 314
Author(s):  
Tianyu Jing ◽  
Huilan Ren ◽  
Jian Li

The present study investigates the similarity problem associated with the onset of the Mach reflection of Zel’dovich–von Neumann–Döring (ZND) detonations in the near field. The results reveal that the self-similarity in the frozen-limit regime is strictly valid only within a small scale, i.e., of the order of the induction length. The Mach reflection becomes non-self-similar during the transition of the Mach stem from “frozen” to “reactive” by coupling with the reaction zone. The triple-point trajectory first rises from the self-similar result due to compressive waves generated by the “hot spot”, and then decays after establishment of the reactive Mach stem. It is also found, by removing the restriction, that the frozen limit can be extended to a much larger distance than expected. The obtained results elucidate the physical origin of the onset of Mach reflection with chemical reactions, which has previously been observed in both experiments and numerical simulations.


Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1115
Author(s):  
Dmitry Zimnyakov ◽  
Marina Alonova ◽  
Ekaterina Ushakova

Self-similar expansion of bubble embryos in a plasticized polymer under quasi-isothermal depressurization is examined using the experimental data on expansion rates of embryos in the CO2-plasticized d,l-polylactide and modeling the results. The CO2 initial pressure varied from 5 to 14 MPa, and the depressurization rate was 5 × 10−3 MPa/s. The constant temperature in experiments was in a range from 310 to 338 K. The initial rate of embryos expansion varied from ≈0.1 to ≈10 µm/s, with a decrease in the current external pressure. While modeling, a non-linear behavior of CO2 isotherms near the critical point was taken into account. The modeled data agree satisfactorily with the experimental results. The effect of a remarkable increase in the expansion rate at a decreasing external pressure is interpreted in terms of competing effects, including a decrease in the internal pressure, an increase in the polymer viscosity, and an increase in the embryo radius at the time of embryo formation. The vanishing probability of finding the steadily expanding embryos for external pressures around the CO2 critical pressure is interpreted in terms of a joint influence of the quasi-adiabatic cooling and high compressibility of CO2 in the embryos.


2014 ◽  
Vol 998-999 ◽  
pp. 1092-1095
Author(s):  
Qi Sheng Zhao ◽  
Xiao Ming Liu ◽  
Hui Sheng Zhu

The information security of wireless sensor networks is one of hot issues on the current research; this paper combines threshold key scheme with the management of security key sharing and group agreement and proposes dynamic key management scheme through clustering level key matrix of authentication mechanism from the cluster to node. The network is divided into different clusters, and the cluster head conducts the key authentication exchange and updates the key management with threshold key schemes, with no need of third authentication center, reduces the computing and communication costs, and promotes communication.


Sign in / Sign up

Export Citation Format

Share Document