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Ronoh, Kennedy, and Awoke Mengistie. "Load Balancing in Heterogeneous LTE-A Networks." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-81208.
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LTE-A is the latest cellular network technology. One feature of LTE-A is the use ofheterogeneous networks (HetNets) which consist of macro-cells and low power nodes(LPNs). One of the objectives of heterogeneous networks is to increase capacity especially inhotspot areas where there is high density of users. Due to their low transmit power, very fewusers associate with LPNs and this will result in load imbalance between LPNs and macrocells.Load balancing is therefore key issue in HetNets so as to maximize cell splitting gainsand ensure even user experiences. Cell range extension (CRE) is a technique that can be usedto achieve load balancing in HetNets. Under CRE, an offset is added to LPNs during cellselection so as to expand the range of LPNs and offload more users from macro-cells toLPNs. CRE usually involves the use of uniform offsets. The use of uniform offsets results insome degree of load balancing in a HetNet which is not optimal. This arises because differentLPNs require different offsets due to varying conditions such as user distribution andpropagation environment in different hotspots. The use of cell-specific offsets is necessary forimproving the level of load balancing in HetNets. In this thesis a heuristic load balancingalgorithm that is used to assign cell-specific offsets to LPNs is designed. The algorithm makesuse of a range optimization framework which applies the concept of cell load coupling. Ourresults show that the use of the cell-specific offsets results in not only a high degree of loadbalancing as measured by Jain’s fairness index but also more even user experiences in termsof throughput.
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Jouini, Hana. "Radio Resource Management in LTE Networks : Load Balancing in Heterogeneous Cellular Networks." Thesis, Paris, CNAM, 2017. http://www.theses.fr/2017CNAM1153/document.
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Face à la croissance exponentielle des réseaux mobiles très haut débit, les opérateurs de téléphonie mobile se sont lancé dans le déploiement des réseaux dits hiérarchiques (HetNet), composés par des sous-réseaux avec des caractéristiques divergentes en termes de type des cellules déployées et des technologies d’accès radio utilisées. Avec ce caractère hétérogène des réseaux cellulaire, l’exploitation de ces derniers devienne de plus en plus compliquée et coûteuse impliquant le déploiement, la configuration et la reconfiguration de stations de base et d’équipements de différentes caractéristiques. Ainsi, l’intégration dans les réseaux HetNet de fonctionnalités d’auto-configuration automatisant et simplifiant l’exploitation des réseaux deviennent une demande forte des opérateurs. Cette thèse a pour objectif l’étude et le développement de solutions de gestion dynamique de l’équilibrage de charges entre les différentes couches composant un même HetNet, pour une expérience utilisateur (QoE) améliorée. Dans ce contexte, une classe des algorithmes d’équilibrage de charges dite ‘équilibrage de charges par adaptation dynamique des paramètres de la procédure de handover’ est étudiée. Pour commencer, nous développons un modèle théorique basé sur des solutions et des outils de la géométrie stochastique et incorporant le caractère hétérogène des réseaux cellulaires. Ensuite nous exploitons ce modèle pour introduire des algorithmes d’adaptation des paramètres de handover basés sur la maximisation de la puissance reçue et du rapport signal/brouillage plus bruit (SINR). Nous exploitons ces résultats pour implémenter et étudier, par simulation à évènements discrets, des algorithmes d’équilibrage de charges dans le contexte des réseaux LTE HetNet auto-organisés basés sur les spécifications 3GPP. Ces travaux soulignent l’importance de l’équilibrage de charges afin de booster les performances des réseaux cellulaires en termes de débit global transmis, perte de paquets de données et utilisation optimisée des ressources radio<br>High demands on mobile networks provide a fresh opportunity to migrate towardsmulti-tier deployments, denoted as heterogeneous network (HetNet), involving a mix of cell types and radio access technologies working together seamlessly. In this context, network optimisation functionalities such as load balancing have to be properly engineered so that HetNet benefit are fully exploited. This dissertation aims to develop tractable frameworks to model and analyze load balancing dynamics while incorporating the heterogeneous nature of cellular networks. In this context we investigate and analyze a class of load balancingstrategies, namely adaptive handover based load balancing strategies. These latter were firstly studied under the general heading of stochastic networks using independent and homogeneous Poisson point processes based network model. We propose a baseline model to characterize rate coverage and handover signalling in K-tier HetNet with a general maximum power based cell association and adaptive handover strategies. Tiers differ in terms of deployment density and cells characteristics (i.e. transmit power, bandwidth, and path loss exponent). One of the main outcomes is demonstrating the impact of offloading traffic from macro- to small-tier. This impact was studied in terms of rate coverage and HO signalling. Results show that enhancement in rate coverage is penalized by HO signalling overhead. Then appropriate algorithms of LB based adaptive HO are designed and their performance is evaluated by means of extensive system level simulations. These latter are conducted in 3GPP defined scenarios, including representation of mobility procedures in both connectedstate. Simulation results show that the proposed LB algorithms ensure performance enhancement in terms of network throughput, packet loss ratio, fairness and HO signalling
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Nyembe, Wiseman Nkosingiphile. "Load balancing using cell range expansion in LTE advanced heterogeneous networks." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20338.
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The use of heterogeneous networks is on the increase, fueled by consumer demand for more data. The main objective of heterogeneous networks is to increase capacity. They offer solutions for efficient use of spectrum, load balancing and improvement of cell edge coverage amongst others. However, these solutions have inherent challenges such as inter-cell interference and poor mobility management. In heterogeneous networks there is transmit power disparity between macro cell and pico cell tiers, which causes load imbalance between the tiers. Due to the conventional user-cell association strategy, whereby users associate to a base station with the strongest received signal strength, few users associate to small cells compared to macro cells. To counter the effects of transmit power disparity, cell range expansion is used instead of the conventional strategy. The focus of our work is on load balancing using cell range expansion (CRE) and network utility optimization techniques to ensure fair sharing of load in a macro and pico cell LTE Advanced heterogeneous network. The aim is to investigate how to use an adaptive cell range expansion bias to optimize Pico cell coverage for load balancing. Reviewed literature points out several approaches to solve the load balancing problem in heterogeneous networks, which include, cell range expansion and utility function optimization. Then, we use cell range expansion, and logarithmic utility functions to design a load balancing algorithm. In the algorithm, user and base station associations are optimized by adapting CRE bias to pico base station load status. A price update mechanism based on a suboptimal solution of a network utility optimization problem is used to adapt the CRE bias. The price is derived from the load status of each pico base station. The performance of the algorithm was evaluated by means of an LTE MATLAB toolbox. Simulations were conducted according to 3GPP and ITU guidelines for modelling heterogeneous networks and propagation environment respectively. Compared to a static CRE configuration, the algorithm achieved more fairness in load distribution. Further, it achieved a better trade-off between cell edge and cell centre user throughputs. [Please note: this thesis file has been deferred until December 2016]
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Ali, Muhammad. "Load balancing in heterogeneous wireless communications networks : optimized load aware vertical handovers in satellite-terrestrial hybrid networks incorporating IEEE 802.21 media independent handover and cognitive algorithms." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/6307.
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Heterogeneous wireless networking technologies such as satellite, UMTS, WiMax and WLAN are being used to provide network access for both voice and data services. In big cities, the densely populated areas like town centres, shopping centres and train stations may have coverage of multiple wireless networks. Traditional Radio Access Technology (RAT) selection algorithms are mainly based on the 'Always Best Connected' paradigm whereby the mobile nodes are always directed towards the available network which has the strongest and fastest link. Hence a large number of mobile users may be connected to the more common UMTS while the other networks like WiMax and WLAN would be underutilised, thereby creating an unbalanced load across these different wireless networks. This high variation among the load across different co-located networks may cause congestion on overloaded network leading to high call blocking and call dropping probabilities. This can be alleviated by moving mobile users from heavily loaded networks to least loaded networks. This thesis presents a novel framework for load balancing in heterogeneous wireless networks incorporating the IEEE 802.21 Media Independent Handover (MIH). The framework comprises of novel load-aware RAT selection techniques and novel network load balancing mechanism. Three new different load balancing algorithms i.e. baseline, fuzzy and neural-fuzzy algorithms have also been presented in this thesis that are used by the framework for efficient load balancing across the different co-located wireless networks. A simulation model developed in NS2 validates the performance of the proposed load balancing framework. Different attributes like load distribution in all wireless networks, handover latencies, packet drops, throughput at mobile nodes and network utilization have been observed to evaluate the effects of load balancing using different scenarios. The simulation results indicate that with load balancing the performance efficiency improves as the overloaded situation is avoided by load balancing.
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Xie, Wanxia. "Supporting Distributed Transaction Processing Over Mobile and Heterogeneous Platforms." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/14073.
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Recent advances in pervasive computing and peer-to-peer computing have opened up vast opportunities for developing collaborative applications. To benefit from these emerging technologies, there is a need for investigating techniques and tools that will allow development and deployment of these applications on mobile and heterogeneous platforms. To meet these challenging tasks, we need to address the typical characteristics of mobile peer-to-peer systems such as frequent disconnections, frequent network partitions, and peer heterogeneity. This research focuses on developing the necessary models, techniques and algorithms that will enable us to build and deploy collaborative applications in the Internet enabled, mobile peer-to-peer environments. This dissertation proposes a multi-state transaction model and develops a quality aware transaction processing framework to incorporate quality of service with transaction processing. It proposes adaptive ACID properties and develops a quality specification language to associate a quality level with transactions. In addition, this research develops a probabilistic concurrency control mechanism and a group based transaction commit protocol for mobile peer-to-peer systems that greatly reduces blockings in transactions and improves the transaction commit ratio. To the best of our knowledge, this is the first attempt to systematically support disconnection-tolerant and partition-tolerant transaction processing. This dissertation also develops a scalable directory service called PeerDS to support the above framework. It addresses the scalability and dynamism of the directory service from two aspects: peer-to-peer and push-pull hybrid interfaces. It also addresses peer heterogeneity and develops a new technique for load balancing in the peer-to-peer system. This technique comprises an improved routing algorithm for virtualized P2P overlay networks and a generalized Top-K server selection algorithm for load balancing, which could be optimized based on multiple factors such as proximity and cost. The proposed push-pull hybrid interfaces greatly reduce the overhead of directory servers caused by frequent queries from directory clients. In order to further improve the scalability of the push interface, this dissertation also studies and evaluates different filter indexing schemes through which the interests of each update could be calculated very efficiently. This dissertation was developed in conjunction with the middleware called System on Mobile Devices (SyD).
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Skagos, P. Takis. "Load balancing in a heterogeneous, distributed environment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq39153.pdf.
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Mohammad, Malik Adeel, and Saeed Muhammad Sheharyar. "Load Balancing in Microwave Networks." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121698.
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Microwave links are very commonly used in carrier networks especially towards the access side. They not only ease deployment of a network but are also very cost effective. However, they bring along a multitude of challenges which are characteristic of the wireless technology. Microwave links are fickle. Being exposed to varying weather conditions, they experience bandwidth fluctuations. This is true especially in the case of links operating at higher frequencies. The unpredictable nature of microwave links makes it quite challenging to plan capacity in a network beforehand. Radio links employ adaptive modulation. They operate on a range on modulation schemes each of which offers different throughput and bit error rates. When operating at a low bit rate modulation scheme, a situation may arise where the microwave link is not able to support the entire traffic incident from the backbone network. As a result, the microwave link will suffer from congestion and packets arriving at the microwave link will eventually be dropped. The switching nodes that precede the microwave link along a communication path are unaware of the microwave link conditions and, therefore, continue to transmit traffic at a high rate. Large carrier networks cannot afford to have performance inconsistencies like data loss and increased latency. Service degradation, even for a very short duration, can have dire consequences in terms of customer dissatisfaction and revenue loss. The goal of this thesis is to use MPLS-TP Linear Protection to load balance traffic across alternative paths in a network where links use adaptive modulation. Rerouted traffic must take other paths so that the congested microwave link is completely avoided. The idea is augmented by the use of a radio condition signaling mechanism between the packet switching node and the microwave node that precede a microwave link. The microwave node sends radio condition control messages to the preceding packet switching node to rate limit traffic and avoid congestion at the microwave link. The result of this thesis work is a system prototype that achieves the stated goal. Evaluation of the prototype is carried out through graphical results, generated by a traffic generator, that advocate the correctness, performance and robustness of the system.
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Saranyan, N. "Prediction based load balancing heuristic for a heterogeneous cluster." Thesis, Indian Institute of Science, 2003. http://hdl.handle.net/2005/95.
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Load balancing has been a topic of interest in both academia and industry, mainly
because of the scope for performance enhancement that is available to be exploited in
many parallel and distributed processing environments. Among the many approaches
that have been used to solve the load balancing problem, we find that only very few
use prediction of code execution times. Our reasoning for this is that the field of code prediction
is in its infancy. As of this writing, we are not aware of any prediction-based
load balancing approach that uses prediction8 of code-execution times, and uses neither
the information provided by the user, nor an off-line step that does the prediction, the
results of which are then used at run-time. In this context, it is important to note that
prior studies have indicated the feasibility of predicting the CPU requirements of general
application programs.
Our motivation in using prediction-based load balancing is to determine the feasibility
of the approach. The reasoning behind that is the following: if prediction-based load
balancing does yield good performance, then it may be worthwhile to develop a predictor
that can give a rough estimate of the length of the next CPU burst of each process. While
high accuracy of the predictor is not essential, the computation overhead of the predictor
must be sufficiently' small, so as not to offset the gain of load balancing.
As for the system, we assume a set of autonomous computers, that are connected by
a fast, shared medium. The individual nodes can vary in the additional hardware and
software that may be available in them. Further, we assume that the processes in the
workload are sequential.
The first step is to fix the parameters for our assumed predictor. Then, an algorithm
that takes into account the characteristics of the predictor is proposed. There are many
trade-off decisions in the design of the algorithm, including certain steps in which we
have relied on trial and error method to find suitable values. The next logical step is
to verify the efficiency of the algorithm. To assess its performance, we carry out event
driven simulation. We also evaluate the robustness of the algorithm with respect to the
characteristics of the predictor.
The contribution of the thesis is as follows: It proposes a load-balancing algorithm
for a heterogeneous cluster of workstations connected by a fast network. The simulation
assumes that the heterogeneity is limited to variability in processor clock rates; but
the algorithm can be applied when the nodes have other types of heterogeneity as well.
The algorithm uses prediction of CPU burst lengths as its basic input unit. The performance
of the algorithm is evaluated through event driven simulation using assumed
workload distributions. The results of the simulation show that the algorithm yields a
good improvement in response times over the scenario in which no load redistribution is
done.
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Wallace, Brian T. "Automated system for load-balancing EBGP peers." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0008800.
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Janjic, Vladimir. "Load balancing of irregular parallel applications on heterogeneous computing environments." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/2540.
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Large-scale heterogeneous distributed computing environments (such as Computational Grids and Clouds) offer the promise of access to a vast amount of computing resources at a relatively low cost. In order to ease the application development and deployment on such complex environments, high-level parallel programming languages exist that need to be supported by sophisticated runtime systems. One of the main problems that these runtime systems need to address is dynamic load balancing that ensures that no resources in the environment are underutilised or overloaded with work. This thesis deals with the problem of obtaining good speedups for irregular applications on heterogeneous distributed computing environments. It focuses on workstealing techniques that can be used for load balancing during the execution of irregular applications. It specifically addresses two problems that arise during work-stealing: where thieves should look for work during the application execution and how victims should respond to steal attempts. In particular, we describe and implement a new Feudal Stealing algorithm and also we describe and implement new granularity-driven task selection policies in the SCALES simulator, which is a work-stealing simulator developed for this thesis. In addition, we present the comprehensive evaluation of the Feudal Stealing algorithm and the granularity-driven task selection policies using the simulations of a large class of regular and irregular parallel applications on a wide range of computing environments. We show how the Feudal Stealing algorithm and the granularity-driven task selection policies bring significant improvements in speedups of irregular applications, compared to the state-of-the-art work-stealing algorithms. Furthermore, we also present the implementation of the task selection policies in the Grid-GUM runtime system [AZ06] for Glasgow Parallel Haskell (GpH) [THLPJ98], in addition to the implementation in SCALES, and we also present the evaluation of this implementation on a large set of synthetic applications.
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Khanna, Varun. "Intelligent load balancing in mobile ad hoc networks." Thesis, Wichita State University, 2010. http://hdl.handle.net/10057/3729.
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On demand ad hoc routing protocols such as AODV and DSR do not look for new routes unless there is a change in the network topology. In scenarios where same intermediate node is used for longer time, this behavior may cause the traffic concentration on few intermediate nodes resulting in large latency and depletion of battery power at the nodes. To overcome this problem, a load balancing algorithm is proposed in this thesis. Each node forwards its residual energy information to all its neighbor nodes using reserved fields in the hello packets. Each node calculates a desirability metric, for each of its neighbor, based on the neighbor‟s energy information and the available bandwidth towards it. The choice of a particular route depends upon the desirability metric of the next hop. The proposed scheme is independent of the underlying routing protocol however the routing protocol should be able to save multiple routes to a destination and be able to put and retrieve the energy information to and from the hello messages.<br>Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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Korzeniowski, Miroslaw. "Dynamic load balancing in peer-to-peer networks." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983620296.
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Du, Lin. "Intelligent geographic load balancing for mobile cellular networks." Thesis, Queen Mary, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414466.
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Wang, Yunlu. "Load balancing in hybrid LiFi and RF networks." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31211.
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The increasing number of mobile devices challenges the current radio frequency (RF) networks. The conventional RF spectrum for wireless communications is saturating, motivating to develop other unexplored frequency bands. Light Fidelity (LiFi) which uses more than 300 THz of the visible light spectrum for high-speed wireless communications, is considered a promising complementary technology to its RF counterpart. LiFi enables daily lighting infrastructures, i.e. light emitting diode (LED) lamps to realise data transmission, and maintains the lighting functionality at the same time. Since LiFi mainly relies on line-of-sight (LoS) transmission, users in indoor environments may experience blockages which significantly affects users' quality of service (QoS). Therefore, hybrid LiFi and RF networks (HLRNs) where LiFi supports high data rate transmission and RF offers reliable connectivity, can provide a potential solution to future indoor wireless communications. In HLRNs, efficient load balancing (LB) schemes are critical in improving the traffic performance and network utilisation. In this thesis, the optimisation-based scheme (OBS) and the evolutionary game theory (EGT) based scheme (EGTBS) are proposed for load balancing in HLRNs. Specifically, in OBS, two algorithms, the joint optimisation algorithm (JOA) and the separate optimisation algorithm (SOA) are proposed. Analysis and simulation results show that JOA can achieve the optimal performance in terms of user data rate while requiring high computational complexity. SOA reduces the computational complexity but achieves low user data rates. EGTBS is able to achieve a better performance/complexity trade-off than OBS and other conventional load balancing schemes. In addition, the effects of handover, blockages, orientation of LiFi receivers, and user data rate requirement on the throughput of HLRNs are investigated. Moreover, the packet latency in HLRNs is also studied in this thesis. The notion of LiFi service ratio is introduced, defined as the proportion of users served by LiFi in HLRNs. The optimal LiFi service ratio to minimise system delay is mathematically derived and a low-complexity packet flow assignment scheme based on this optimum ratio is proposed. Simulation results show that the theoretical optimum of the LiFi service ratio is very close to the practical solution. Also, the proposed packet flow assignment scheme can reduce at most 90% of packet delay compared to the conventional load balancing schemes at reduced computational complexity.
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Dacre, Marcus James. "Stochastic scheduling in networks." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285800.
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Cheung, Lap-sun. "Load balancing in distributed object computing systems." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2329428.
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Yildiz, Ali. "Resource-aware Load Balancing System With Artificial Neural Networks." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607613/index.pdf.
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As the distributed systems becomes popular, efficient load balancing systems taking
better decisions must be designed. The most important reasons that necessitate load
balancing in a distributed system are the heterogeneous hosts having different com-
puting powers, external loads and the tasks running on different hosts but communi-
cating with each other. In this thesis, a load balancing approach, called RALBANN,
developed using graph partitioning and artificial neural networks (ANNs) is de-
scribed. The aim of RALBANN is to integrate the successful load balancing deci-
sions of graph partitioning algorithms with the efficient decision making mechanism
of ANNs. The results showed that using ANNs to make efficient load balancing can
be very beneficial. If trained enough, ANNs may load the balance as good as graph
partitioning algorithms more efficiently.
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Zhou, Zhunyan. "Routing with load balancing in wireless ad hoc networks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ55943.pdf.
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Tall, Hamadoun. "Load balancing in multichannel data collection wireless sensor networks." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC006/document.
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Les Réseaux de Capteurs Sans Fil (RCSF) sont de plus en plus exploités par des applications diverses grâce à leur facilité de déploiement et d’auto-configuration. Les applications de collecte de données qui utilisent les RCSF ont souvent un profil convergecast : l’ensemble des données récoltées par tous les capteurs du réseau sont acheminées vers un puits de collecte, grâce à une communication multi-saut. Pendant l’acheminement des données des nœuds de collecte vers le puits, des goulots d’étranglement sont fréquemment observés, principalement au voisinage du puits. Cela est du à la congestion et au phénomène d’entonnoir couramment observé sur le trafic de données ayant un profile convergecast. Outre un risque accru de collision, cela entraîne le débordement des files d’attente des nœuds concernés conduisant à des pertes de données. Cette perte réduit le taux de livraison au puits entraînant une baisse du débit du réseau. Afin de réduire ces pertes et de permettre un meilleur taux de livraison au puits, le trafic doit être équitablement réparti au niveau de chaque saut pendant l’acheminement. Dans cette thèse, nous avons d’une part proposé S-CoLBA (Single channel Collaborative Load Balancing Algorithm), un protocole mono-canal de routage dynamique avec équilibrage de la charge. Sa métrique de routage est basée sur le délais moyen d’accès au medium radio par nœud. Chaque nœud choisit comme prochain saut à destination du puits, un de ses voisins ayant le délais d’accès le plus court. S-CoLBA intègre également une surveillance permanente des files d’attente des nœuds afin de prévenir la congestion et d’éviter le débordement de ces files. D’autre part, nous avons adapté S-CoLBA pour le rendre utilisable dans un réseau multicanal. Cette version du protocole s’appelle M-CoLBA (pour Mulitchannel CoLBA). M-CoLBA évite la congestion en équilibrant la charge grâce à une répartition du trafic au niveau de chaque saut du réseau. Dans un réseau multicanal, le problème de support de diffusion se pose. M-CoLBA introduit des périodes de synchronisations où tous les nœuds utilisent le même canal pour échanger les informations de routage. Ces périodes de synchronisation contribuent à allonger les délais de bout en bout des paquets. Nous avons ainsi optimisé M-CoLBA en "surchargeant" les acquittements des trames avec les informations de routage ( piggybacking) et les états des files d’attente. Cela évite de passer par des périodes de synchronisation pour diffuser ces informations. Cette version optimisée s’appelle ABORt ( Acknowledgement-Based opportunistic Routing protocol). Dans un cas de trafic de type convergecast, ABORt induit une diversité des routes prises par les données collectées, ce qui est bénéfique à la quantité de données transportées et à la robustesse de la solution. Les contributions ont été évaluées par simulation et expérimentation dans un réseau monocanal et multicanal. Les résultats montrent que nos contributions améliorent le taux de livraison des données au puits, optimisent le délais de bout en bout et réduisent la quantité de trafic de contrôle comparé à des solutions déjà existantes<br>The popularity of wireless sensor networks (WSNs) is increasing due to their ease ofdeployment and auto-configuration capabilities. They are used in different applica-tion domains including data collection with convergecast scenarios. In convergecast,all data collected in the network is destined to one common node usually called thesink. In case of high carried traffic load and depending on the used routing policy,this many-to-one data collection leads to congestion and queue overflow mainly innodes located near the sink. Congestion and queue overflow reduce delivery ratiothat negatively affects the network efficiency.Wireless sensor nodes are resource constrained devices with limited buffers sizeto store and forward data to the sink. Introducing multichannel communication inWSNs helps to increase the carried traffic load thanks to allowing parallel data trans-mission and reduction of contention and interference. With high traffic load, thenumber of data packets travelling from leaf nodes towards the sink becomes higher.In case the routing scheme does not balance the traffic load, it will be unfairly dis-tributed between forwarding nodes. Thus, nodes that are in part of the routing will beoverloaded while others are less used. Overloaded nodes increase the risk of conges-tion and queue overflow leading to data loss that reduces the throughput. Therefore,we need to couple the routing protocols with traffic load balancing scheme in hightraffic load network scenarios.The goal of this thesis is to propose an efficient routing solution to prevent con-gestion and queue overflow in high data rate convergecast WSNs, in such a way, tooptimize data delivery ratio at the sink node.On the one hand, we proposed a single channel traffic load balancing routingprotocol, named S-CoLBA (Single channel Collaborative Load balancing routing).It relies on data queueing delay metric and best score (according to the value of themetric) next hop neighbors to fairly distribute traffic load in per hop basis in the net-work. Since the carried traffic load increases in multichannel communication, onthe other hand, we adapted our contribution to cope with multichannel WSNs andwe named it as Multichannel CoLBA (M-CoLBA). As broadcasting information isnot straightforward in multichannel, we optimize M-CoLBA to use piggybackingscheme for routing information sharing in the network. This enhanced version iscalled ABORt for Acknowledgement-Based opportunistic Routing protocol and re-lies on ACK frames to share routing information. Doing so helps to optimize dataframe end-to-end delay and to reduce the transmitted beacons in the network. ABORtfairly distributes traffic load in the network and avoids congestion and queue over-flow.We evaluated the performance of our contributions in both simulation using Con-tiki OS Cooja simulator and experiment (only for S-CoLBA) on TelosB motes. Ob-tained results in both simulation and experiment confirm the efficiency of our routingprotocols in term of packet delivery ratio and queue overflow compared to some ex-isting routing protocols in the literature
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張立新 and Lap-sun Cheung. "Load balancing in distributed object computing systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31224179.
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Faizan, Jahanzeb. "Introducing reliability and load balancing in Mobile IPv6 based networks." Ann Arbor, Mich. : ProQuest, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3203791.
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Thesis (Ph.D. in Computer Science)--S.M.U.<br>Title from PDF title page (viewed July 5, 2007). Source: Dissertation Abstracts International, Volume: 66-12, Section: B, page: 6721. Adviser: Hesham El-Rewini. Includes bibliographical references.
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White, Kevin A. "Tactical network load balancing in multi-gateway wireless sensor networks." Thesis, Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/39036.
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Approved for public release; distribution is unlimited.<br>A tactical wireless sensor network (WSN) is a distributed network that facilitates wireless information gathering within a region of interest. For this reason, WSNs are finding increased use by the Department of Defense. A challenge in the deployment of WSNs is the limited battery power of each sensor node. This has a significant impact on the service life of the network. In order to improve the lifespan of the network, load balancing techniques using efficient routing mechanisms must be employed such that traffic is distributed between sensor nodes and gateway(s). In this thesis, we study load balancing from a cross-layer point of view, specifically considering energy efficiency. We investigate the impact of deploying single and multiple gateways on the following established energy aware load balancing routing techniques: direct routing, minimum transmission energy, low energy adaptive cluster head routing, and zone clustering. Based on the node die out statistics observed with these protocols, we develop a novel, energy efficient zone clustering algorithm called EZone. Via extensive simulations using MATLAB, we analyze the effectiveness of these algorithms on network performance for single and multiple gateway scenarios and show that the EZone algorithm maximizes network lifetime and service area coverage.
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Oliveira, Marco Rafael Tenrinho. "Mobility in vehicular networks with dynamic connectivity and load balancing." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16401.
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Mestrado em Engenharia Eletrónica e Telecomunicações<br>With the evolution of technology and the demands of population, the technological advances are leading to the so called internet of things and, in its turn, the development of the internet of things leads to the creation of new objectives and to the utilization of new approaches regarding access networks. Besides, the stable communication is also desired independently of the access technology in use. Nowadays the importance of being connected always and everywhere is increasing, independently of the access conditions. The usage of vehicular networks is getting to a reality, and they are used with several objectives and providing several services. In this way, this kind of networks can already provide services to the community like internet connection inside the vehicle, gather data from the city and, when the deployment extends to common users, some features like road safety and autonomous driving will be possible. With the dynamicity of these networks it is usual that one node is in reach of more than one access point, but when this happens, that node will just connect to one of them independently of the good quality of those access points. Besides, with the high mobility of the nodes in the network, the amount of changes in the way the network is connected is high, which leads to the importance of having always a good connection and a fast change between networks when needed. This dissertation focuses on the need to guarantee that one node connects simultaneously to several access points to the network and providing fast mobility of the nodes in a transparent manner to the users. Therefore, the integration between the N-PMIPv6 mobility protocol and a PMIPv6 multihoming support extension is performed. Several entities that support multihoming are integrated and adapted to the characteristics/operation of N-PMIPv6 in the way that they are as adapted as possible to the vehicular conditions. Also, a particularity of the WAVE vehicular technology is used so that one interface can connect to more than one access point at the same time. Besides, the traffic to the users is distributed in such a way that it accounts for the characteristics of the networks and of that same traffic. Regarding the connections performed, the entity that manages them is improved so that it can support more than one at the same time. Finally, a mobility protocol for vehicular networks is obtained that supports simultaneous connections to the network, in which those connections can be seen and treated as belonging to the same user. Besides, the laboratory and road tests show that a division of the traffic through the several paths is performed in a way that it minimizes delay, maximizes the utilization of WAVE and minimizes the possible out-of-order packets.<br>Com a evolução da tecnologia e da mentalidade do público em geral, cada vez mais os avanços tecnológicos levam à chamada internet das coisas e, por sua vez, a internet das coisas leva à criação de novos objetivos e à utilização de novas abordagens no que diz respeito às redes de acesso. Além dessa evolução, deseja-se também a comunicação estável e independentemente da tecnologia de acesso. Atualmente torna-se cada vez mais importante estar ligado em todo lado e a toda a hora, independentemente das condições de acesso. A utilização das redes veiculares é cada vez mais uma realidade, sendo estas já utilizadas com vários objetivos e fornecendo variados serviços. Neste sentido, estes tipos de redes já podem fornecer atualmente vários serviços à comunidade, nomeadamente a ligação à internet dentro do veículo, a recolha e utilização de dados sobre a cidade e, quando a utilização for estendida a veículos de utilizadores comuns, será possível o suporte para a segurança rodoviária e até condução autónoma. Com a dinamicidade destas redes é comum um nó estar ao alcance de mais do que um ponto de acesso, mas quando isso acontece, apenas se liga a um deles independentemente da boa qualidade de ambos. Além disso, com a grande mobilidade dos nós da rede, a quantidade de alterações relativas ao ponto de acesso à rede é bastante grande, o que leva à extrema importância de garantir sempre uma boa ligação e uma rápida alteração da ligação sempre que necessário. Esta dissertação concentra-se na necessidade de garantir a ligação simultânea a vários pontos de acesso à rede e uma rápida mobilidade dos nós de uma forma transparente para o utilizador. Com este objetivo, é realizada a integração do protocolo de mobilidade de rede Network PMIPv6 (N-PMIPv6) com uma extensão de suporte ao multihoming para o Proxy Mobile IPv6 (PMIPv6). Nesta integração as várias entidades que suportam o multihoming são integradas e adaptadas às características/ funcionamento do N-PMIPv6 de maneira a que estas estejam o mais adaptadas possível às condições das redes veiculares. É também utilizada uma particularidade da tecnologia veicular Wireless Access in Vehicular Environments (WAVE) para proceder a várias ligações com uma só interface. Além disso, o tráfego destinado aos utilizadores é distribuído tendo em conta as características das redes e do próprio tráfego. Relativamente às ligações efetuadas, a entidade de decisão e execução de ligações à rede é melhorada para permitir a ligação a vários pontos de acesso em simultâneo. Por fim, obtém-se um protocolo de mobilidade para redes veiculares que suporta ligações simultâneas à rede, em que essas ligações são vistas e tratadas como pertencendo ao mesmo utilizador. Além disso, os testes de laboratório e estrada mostram que se consegue efetuar uma divisão do tráfego pelos vários caminhos minimizado o delay, maximizando a utilização de WAVE e minimizando os possíveis pacotes fora de ordem.
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TOSHNIWAL, RISHI. "DYNAMIC CONFIGURATION AND LOAD BALANCING IN BLUETOOTH PERSONAL AREA NETWORKS." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1037911162.
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Groleau, Romain. "Multipath Routing with Load Balancing in Wireless Ad Hoc Networks." Thesis, KTH, Mikroelektronik och Informationsteknik, IMIT, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-92299.
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In recent years, routing research concerning wired networks has focused on minimizing the maximum utilization of the links which is equivalent to reducing the number of bottlenecks while supporting the same traffic demands. This can be achieved using multipath routing with load balancing instead of single path routing using of routing optimizers. However, in the domain of ad hoc networks multipath routing has not been investigated in depth. We would like to develop an analogy between wired and wireless networks, but before that we need to identify the major differences between these two in the case of multipath routing. First, in order to increase the network throughput, the multiple paths have to be independent so they don't share the same bottlenecks. Then, due to radio propagation properties the link capacity is not constant. So using the maximum utilization metric for wireless networks is not suitable. Based on the research done in wired networks, which has shown that using multiple paths with load balancing policies between sourcedestination pairs can minimize the maximum utilization of the links, we investigate if this is applicable to ad hoc networks. This paper proposes a multipath routing algorithm with a load balancing policy. The results obtained from an indoor 802.11g network highlight two major points. The maximum throughput is not achieved with multipath routing, but with single path routing. However, the results on the delivery ratio are encouraging, indeed we observe a real improvement thanks to our multipath routing algorithm.<br>På senare år har routning forskningen angående trådnätverken focusen på att minska den maximala användingen av länkar vilket motsvarar än reducering av flaskhalsar medan man stöder samma trafikkrav. Det här kan åstadkommas genom att av multiväg routning med lasta balansering I stället för använder enkelvägrouting med routing optimizers. Emellertid har inom ad hoc nätverken multiväg routning har inte blivit undersökts på djupet. Vi skulle vilja utveckla en analogy emellan trådnätverk och trådlösnätverken.men främföre det behöver identifiera de store differenserna mellan dessa två vid multiväg routning. För det första måste de flerfaldiga vägarna vara oberoende för att öka nätverkens throughput så de inte delar samma flaskhalsar. Sedan är länkkapaciteten inte constant på grund av radiospridningsegenskaperna. Så den maximal användningsmetric för trådlös nätverken passar inte. Den här arbetetet föreslår en multiväg routning algoritm med lasta balanseringen. Resultaten få från en indoor 802.11g nätverk framhåller ger två store meningen. Den maximala throughput är inte åstadkoms med multiväg routing, men med enkelväg routning. Emellertid är resultaten på den leveransförhållande uppmuntrande; vi observera en verklig förbättring tack vare vår multiväg routning algoritmen.
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Kleerekoper, Anthony. "Distributed load balancing in many-to-one wireless sensor networks." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/distributed-load-balancing-in-manytoone-wireless-sensor-networks(b282c4bc-e4b0-4440-9cad-57ebb28b167f).html.
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A typical sensor network is conceived as being a very large collection of low-powered, homogeneous nodes that remain static post-deployment and forward sensed data to a single sink via multi-hop communication. For these types of networks there is an inherent funnelling effect whereby the nodes that can communicate directly with the sink must collectively forward the traffic of the entire network and therefore these nodes use more energy than the other nodes. This is known as the energy hole problem because after some time, these nodes deplete their batteries and leave an energy hole cutting the sink off from the network.In this thesis two new routing protocols are proposed that aim to maximise load balancing among these most critical nodes in order to maximise lifetime. They are the first fully distributed routing protocols that are designed to generate a load balanced routing tree to mitigate the energy hole problem. The results show that the better performing of the two is capable of creating a highly balanced tree at the cost of a small increase in latency.Although there have been other fully distributed protocols that aim at a similar form of load balancing, it is proven that the approach they take cannot guarantee perfect balance among the most critical nodes even in unrealistically generous scenarios. This suggests that they are not well suited to that task and the simulation results show that the novel protocols proposed in this thesis outperform the best of the alternatives.Before these protocols are proposed, the absolute reception-based blacklisting routing strategy is shown to be more energy efficient than previously thought and indeed more efficient than the strategy that has previously been considered optimal. This result is used to strongly justify the use of the unit disk graph model in simulations of sensor networks. Additionally, the relay hole problem in sensor networks is analysed for the first time.
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Caliskanelli, Ipek. "A bio-inspired load balancing technique for wireless sensor networks." Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/7030/.
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Wireless Sensor Networks (WSNs) consist of multiple distributed nodes each with limited resources. With their strict resource constraints and application-specific characteristics, WSNs contain many challenging trade-offs. This thesis is concerned with the load balancing of Wireless Sensor Networks (WSNs). We present an approach, inspired by bees’ pheromone propagation mechanism, that allows individual nodes to decide on the execution process locally to solve the trade-off between service availability and energy consumption. We explore the performance consequences of the pheromone-based load balancing approach using a system-level simulator. The effectiveness of the algorithm is evaluated on case studies based on sound sensors with different scenarios of existing approaches on variety of different network topologies. The performance of our approach is dependant on the values chosen for its parameters. As such, we utilise the Simulated Annealing to discover optimal parameter configurations for pheromone-based load balancing technique for any given network schema. Once the parameter values are optimised for the given network topology automatically, we inspect improving the pheromone-based load balancing approach using robotic agents. As cyber-physical systems benefit from the heterogeneity of the hardware components, we introduce the use of pheromone signalling-based robotic guidance that integrates the robotic agents to the existing load balancing approach by guiding the robots into the uncovered area of the sensor field. As such, we maximise the service availability using the robotic agents as well as the sensor nodes.
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Carlino, Charles. "An experiment in the complexity of load balancing algorithms /." Online version of thesis, 1991. http://hdl.handle.net/1850/11057.
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Zheng, Chunfang. "GRAPHICAL MODELING AND SIMULATION OF A HYBRID HETEROGENEOUS AND DYNAMIC SINGLE-CHIP MULTIPROCESSOR ARCHITECTURE." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/249.
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A single-chip, hybrid, heterogeneous, and dynamic shared memory multiprocessor architecture is being developed which may be used for real-time and non-real-time applications. This architecture can execute any application described by a dataflow (process flow) graph of any topology; it can also dynamically reconfigure its structure at the node and processor architecture levels and reallocate its resources to maximize performance and to increase reliability and fault tolerance. Dynamic change in the architecture is triggered by changes in parameters such as application input data rates, process execution times, and process request rates. The architecture is a Hybrid Data/Command Driven Architecture (HDCA). It operates as a dataflow architecture, but at the process level rather than the instruction level. This thesis focuses on the development, testing and evaluation of a new graphic software (hdca) developed to first do a static resource allocation for the architecture to meet timing requirements of an application and then hdca simulates the architecture executing the application using statically assigned resources and parameters. While simulating the architecture executing an application, the software graphically and dynamically displays parameters and mechanisms important to the architectures operation and performance. The new graphical software is able to show system and node level dynamic capability of the HDCA. The newly developed software can model a fixed or varying input data rate. The model also allows fault tolerance analysis of the architecture.
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Kodela, Venkatesh. "Improving load balancing mechanisms of software defined networks using open flow." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10141520.
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<p> Software Defined Networks (SDNs) are an active research topic in Networking. This project proposes an approach to a load balancer with the implementation of SDN. This SDN load balancer uses the Round-Robin algorithm. The design topology consists of the SDN-switch and an Open Day Light (ODL) controller. The packet entries are kept in the flow table that are stored in the data plane. This project separates the control and data plane and regulates the controller using ODL. This separation eases the controlling of load balancers. By using this technique, the system becomes directly programmable and agile. The requests from different clients will be directed to various pre-defined servers in the Round-Robin fashion. This project successfully achieves load balancing using the SDN controller and reduces the response time as well as the latency.</p>
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Wang, Xuan. "A Load Balancing Algorithm for Flow Management in Hybrid-SDN Networks." Thesis, University of South Dakota, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10937380.
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<p> Hybrid Software Defined Network(Hybrid-SDN) is the most popular topic in recent years, with related development and deployment of vendors of software and hardware. HybridSDN has the capabilities of most advantaged technology and features with the network current on use in public. However, the Hybrid-SDN does not have the highest performance which is the pure SDN network architecture. It is necessary for researchers understand the differences between legacy network, SDN and Hybrid-SDN, through the numeric comparison of performances by simulations. Also, as the cooperation part between the legacy nodes and SDN nodes in Hybrid-SDN network architecture, load balancing algorithm played an important role. There are lots of load balancing algorithm comes out since the network architecture first time constructed. But the different between load balancing algorithms are not clear. It is necessary for researchers know is there existing difference between load balancing algorithms. Also, particular for Hybrid-SDN network architecture, the messed up environment of different type of devices, the current existing load balancing algorithm did not considering all the cases may affect the network. The solution for the problem is to design a load balancing algorithm which particular focusing on Hybrid-SDN environment. To explain the differences of these framework and design the load balancing algorithm, we studied different network architectures and load balancing algorithms, evaluated them by simulation results. The main work included the following tasks:</p><p> • Simulated three network architectures. • Simulated two common load balancing algorithms. • Designed a load balancing algorithm for flow management focus on Hybrid-SDN</p><p> The simulation results of three network architectures provided the clearly differences between these architectures, which approve the Hybrid-SDN has a big performance promotion with Legacy Network. The results of two load balancing algorithms showed there existing difference between load balancing algorithms, so that, it is necessary to have a load balancing algorithm particular focusing on Hybrid-SDN. And both analysis and simulation results dedicated that our proposed load balancing algorithm can perform efficiently for Hybrid-SDN network architecture.</p><p>
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Joshi, Avinash. "Load Balancing, Queueing and Scheduling Mechanisms in Mobile Ad Hoc Networks." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1004447615.
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Deshpande, Isha Sanjay. "HETEROGENEOUS COMPUTING AND LOAD BALANCING TECHNIQUES FOR MONTE CARLO SIMULATION IN A DISTRIBUTED ENVIRONMENT." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1308244580.
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Tsiakas, Panagiotis. "Adaptive load balancing routing algorithms for the next generation wireless telecommunications networks." Thesis, Brunel University, 2009. http://bura.brunel.ac.uk/handle/2438/7509.
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With the rapid development of wireless networks, mesh networks are evolving as a new important technology, presenting a high research and commercial interest. Additionally, wireless mesh networks have a wide variety of applications, offering the ability to provide network access in both rural and urban areas with low cost of maintenance. One of the main functionalities of a wireless mesh network is load balancing routing, which is the procedure of finding the best, according to some criteria, routes that data need to follow to transfer from one node to another. Routing is one of the state-of-the-art areas of research because the current algorithms and protocols are not efficient and effective due to the diversity of the characteristics of these networks. In this thesis, two new routing algorithms have been developed for No Intra-Cell Interference (NICI) and Limited Intra-Cell Interference (LICI) networks based on WiMAX, the most advanced wireless technology ready for deployment. The algorithms created are based on the classical Dijkstra and Ford-Fulkerson algorithms and can be implemented in the cases of unicast and multicast transmission respectively.
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Singh, Sarabjot active 21st century. "Load balancing in heterogeneous cellular networks." Thesis, 2014. http://hdl.handle.net/2152/28387.
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Pushing wireless data traffic onto small cells is important for alleviating congestion in the over-loaded macrocellular network. However, the ultimate potential of such load balancing and its effect on overall system performance is not well understood. With the ongoing deployment of multiple classes of access points (APs) with each class differing in transmit power, employed frequency band, and backhaul capacity, the network is evolving into a complex and “organic” heterogeneous network or HetNet. Resorting to system-level simulations for design insights is increasingly prohibitive with such growing network complexity. The goal of this dissertation is to develop realistic yet tractable frameworks to model and analyze load balancing dynamics while incorporating the heterogeneous nature of these networks. First, this dissertation introduces and analyzes a class of user-AP association strategies, called stationary association, and the resulting association cells for HetNets modeled as stationary point processes. A “Feller-paradox”-like relationship is established between the area of the association cell containing the origin and that of a typical association cell. This chapter also provides a foundation for subsequent chapters, as association strategies directly dictate the load distribution across the network. Second, this dissertation proposes a baseline model to characterize downlink rate and signal-to-interference-plus-noise-ratio (SINR) in an M-band K-tier HetNet with a general weighted path loss based association. Each class of APs is modeled as an independent Poisson point process (PPP) and may differ in deployment density, transmit power, bandwidth (resource), and path loss exponent. It is shown that the optimum fraction of traffic offloaded to maximize SINR coverage is not in general the same as the one that maximizes rate coverage. One of the main outcomes is demonstrating the aggressive of- floading required for out-of-band small cells (like WiFi) as compared to those for in-band (like picocells). To achieve aggressive load balancing, the offloaded users often have much lower downlink SINR than they would on the macrocell, particularly in co-channel small cells. This SINR degradation can be partially alleviated through interference avoidance, for example time or frequency resource partitioning, whereby the macrocell turns off in some fraction of such resources. As the third contribution, this dissertation proposes a tractable framework to analyze joint load balancing and resource partitioning in co-channel HetNets. Fourth, this dissertation investigates the impact of uplink load balancing. Power control and spatial interference correlation complicate the mathixematical analysis for the uplink as compared to the downlink. A novel generative model is proposed to characterize the uplink rate distribution as a function of the association and power control parameters, and used to show the optimal amount of channel inversion increases with the path loss variance in the network. In contrast to the downlink, minimum path loss association is shown to be optimal for uplink rate coverage. Fifth, this dissertation develops a model for characterizing rate distribution in self-backhauled millimeter wave (mmWave) cellular networks and thus generalizes the earlier multi-band offloading framework to the co-existence of current ultra high frequency (UHF) HetNets and mmWave networks. MmWave cellular systems will require high gain directional antennas and dense AP deployments. The analysis shows that in sharp contrast to the interferencelimited nature of UHF cellular networks, mmWave networks are usually noiselimited. As a desirable side effect, high gain antennas yield interference isolation, providing an opportunity to incorporate self-backhauling. For load balancing, the large bandwidth at mmWave makes offloading users, with reliable mmWave links, optimal for rate.<br>text
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Weng, Chih-Hsueh, and 翁志學. "Design of the SCTP Load Balancing over Heterogeneous Networks." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/35770670894777998061.
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碩士<br>逢甲大學<br>通訊工程所<br>97<br>For the next generation of networking environment in the future, the structure of access network will be made up of a combination of different characteristics, utilizing SCTP newly added characteristics of Multi-homing for the integration and application of different access networks, It will allow for the proper allocation and management in accordance with different access network’s characteristics and bandwidth.
The thesis will follow the proposed theory put forward by the load balancing algorithm, to analyze the relationships between network environment’s arrival rate and service rate, dynamically calculates each outgoing link’s weight distribution, and at the same time dynamically detects all the available bandwidth for the network environment; thus realizing the goal of dynamic adjustment in accordance with the weight, and transmits data using multiple routes to enhance the data transmission volume and effectively solve issues from multi-path transmission, and achieving network resources reallocation and the maximum of cable utilization.
Finally in accordance with the network simulation software NS2 and adding the proposed algorithm, SCTP’s external line weights will be dynamically adjusts, using SCTP protocol as the bases, in order to achieve the dynamic adjustment of the load balancing mechanism, through experimentation to analysis the test result.
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Lin, Shih-Hao, and 林士豪. "Performance Evaluation of Load Balancing in Heterogeneous Cellular Networks." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/33549428454377565510.
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碩士<br>國立臺灣科技大學<br>資訊工程系<br>102<br>The diverse characteristics of base stations (BSs) in two-tier macro/femto heterogeneous cellular networks (HCN) might lead unbalanced loading among them, which significantly affects the performance of HCN. How to design a suitable load balancing strategy is a critical issue and obviously we need an efficient model to evaluate the performance of proposed model. To precisely model the behaviors of BSs in each tier deployed in irregular fashion, this thesis adopts stochastic geometry. A self-configured threshold-based strategy without communication overheads among BSs in each tier is proposed as the baseline load balancing strategy. Two novel performance metrics, switch probability and isolated probability, are proposed to evaluate the performance of the threshold-based strategy. We also conduct simulation experiments according to data from OpenCellID web site to prove the effectiveness of the proposed mathematical models in the realistic two-tier HCNs.
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Kumar, Basaba Bikram, and Basaba Bikram Kumar. "User Association Schemes for Load Balancing in Wireless Heterogeneous Networks." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107CGU05442011%22.&searchmode=basic.
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Yeh, Kuan-Hsuan, and 葉洸亘. "Dynamic Interference Mitigation and Load Balancing for eICIC in Heterogeneous Networks." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/hd9fhb.
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碩士<br>國立交通大學<br>電信工程研究所<br>103<br>Enhanced Inter-cell Interference Coordination (eICIC) is one of the most popular techniques used to mitigate the interference problem in heterogeneous networks. This thesis investigates the dynamic eICIC mechanism with quality of service (QoS) requirements in wireless communication systems. Because of the user mobility and traffic dynamics, the dynamic eICIC mechanism is necessary in modern wireless networks. With QoS requirements, users could utilize the system resources efficiently under the dynamic eICIC mechanism. In order to evaluate the system performance in different aspects, the throughput and fairness are selected as the metrics. We firstly use a modified sum-rate utility as the throughput metric, and propose a dynamic eICIC strategy for the system sum throughput maximization. Then we choose a proportional fairness utility as the fairness metric, and propose a dynamic eICIC strategy for proportional fairness maximization. Finally, computer simulations show that the performance of the dynamic eICIC mechanism with QoS requirements is better than the static eICIC mechanism and conventional dynamic eICIC mechanism in different scenarios.
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Liu, Chun-Yi, and 劉俊毅. "Vertical Handoff and Load Balancing for Heterogeneous Wireless Networks using Combinatorial Fusion." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/dzhyqa.
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博士<br>國立清華大學<br>資訊工程學系所<br>105<br>Network selection in Heterogeneous Wireless Networks (HWN) aims to select the best network for a variety of communication tasks at any time and anywhere. Due to its importance and necessity, it has been studied using various mathematical models including game theory, multiple attribute decision making (MADM), Markov chain, and fuzzy logic. Since these models have different features and functions to produce different results, it has been suggested to combine these models in order to harness the benefit of individual model. However, it remains a challenge to decide when and how to combine these models or systems.
In this thesis, we propose a new approach to study the network selection problem in HWN using combinatorial fusion. More specifically, we investigate: (a) vertical handoff decision to fuse three metrics: received signal strength (RSS), data rate, and network latency using fuzzy logic and combinatorial fusion; and (b) load balancing using combinatorial fusion on three metrics: RSS, accumulated message queue length, and channel utilization. Experimental results demonstrated that our method can make network selection much simpler and more effective. Our work provides a novel way to fuse these metrics for network selection. It is also the first method to integrate fuzzy logic and combinatorial fusion in solving the network selection problem in heterogeneous wireless network.
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Sin-BeiWu and 吳欣蓓. "A Novel Handover Process for Mobility Load Balancing in LTE Heterogeneous Networks." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/njwvaf.
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沈瑞璋. "A Comparison Between the Load-Balancing Metrics Among APs for Heterogeneous Wireless Networks." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70891664327133286952.
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Ali, Muhammad, Prashant Pillai, Yim Fun Hu, Kai J. Xu, Yongqiang Cheng, and Anju Pillai. "Fuzzy based CRRM for load balancing in heterogenous wireless networks." 2013. http://hdl.handle.net/10454/9602.
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No<br>The ever increasing user QoS demands and emergence of new user applications make job of network operators and manufacturers more challenging for efficiently optimisation and managing radio resources in radio the radio resources pools of different wireless networks. A group of strategies or mechanisms which are collectively responsible for efficient utilisation of radio resources available within the Radio Access Technologies (RAT) are termed as Radio Resource Management (RRM). The traditional RRM strategies are implemented independently in each RAT, as each RRM strategy considers attributes of a particular access technology. Therefore traditional RRM strategies are not suitable for heterogeneous wireless networks. Common Radio Resource Management (CRRM) or joint radio resource management (JRRM) strategies are proposed for coordinating radio resource management between multiple RATs in an improved manner. In this paper a fuzzy algorithm based CRRM strategy is presented to efficiently utilise the available radio resources in heterogeneous wireless networks. The proposed CRRM strategy balances the load in heterogeneous wireless networks and avoids the unwanted congestion situation. The results such as load distribution, packet drop rate and average throughput at mobile nodes are used to demonstrate the benefits of load balancing in heterogeneous wireless networks using proposed strategy.
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Ali, Muhammad, Prashant Pillai, and Yim Fun Hu. "Load-aware radio access selection in future generation wireless networks." 2013. http://hdl.handle.net/10454/9601.
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No<br>In the telecommunication networks the introduction of Next Generation Wireless Networks (NGWN) has been described as the most significant change in wireless communication. The convergence of different access networks in NGWN allows generalized mobility, consistency and ubiquitous provision of services to mobile users. The general target of NGWN is to transport different types of information like voice, data, and other media like video in packets form like IP. The NGWNs offer significant savings in costs to the operators along with new and interesting services to the consumers. Major challenges in NGWN are efficient resource utilization, maintaining service quality, reliability and the security. This paper proposes a solution for seamless load aware Radio Access Technology (RAT) selection based on interworking of different RATs in NGWN. In this paper novel load balancing algorithms have been proposed which have been simulated on the target network architecture for TCP data services. The IEEE 802.21 Media Independent Handover (MIH) is utilized in load balancing specifically for mobility management, which enable low handover latency by reducing the target network detection time. The proposed method considers the network type, signal strength, data rate and network load as primary decision parameters for RAT selection process and consists of two different algorithms, one located in the mobile terminal and the other at the network side. The network architecture, the proposed load balancing framework and RAT selection algorithms were simulated using NS2. Different attributes like load distribution in the wireless networks and average throughput to evaluate the effects of load balancing in considered scenarios.
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Steiner, Mark G. "Simulation and close-to-optimal algorithm for the static load balancing of a network of heterogeneous processors." Thesis, 2002. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2002-090.
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Chen, Yueh Ren, and 陳躍仁. "Prediction-Based Load Balancing in Heterogeneous Environment." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/13541281458387784872.
Full textAbstract:
碩士<br>國立中山大學<br>資訊工程研究所<br>83<br>In heterogeneous distributed environment, load balancing is
very important for overall system performance improvement. But
load balancing is not a easy work. So in this thesis, we will
use benchmark to normalize the difference between the systems
and establish a prediction system to forecast the future load
variation by some techniques like linear regression and pattern
composition. This system will help users to decide the best
host to execute their programs for the maximum utilization of
all system resources. And it is hard to write distributed
applications in heterogeneous environment, too. For this
reason, we provide a transparency tool --- modified PVM, which
scheduler has been improved by our prediction system to
automatically balance the system load for more efficient system
performance.
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Huang, Yu-Jr, and 黃裕智. "Load Balancing Policies in Heterogeneous Distributed Systems." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/84806105245925679307.
Full textAbstract:
碩士<br>大同工學院<br>資訊工程研究所<br>81<br>This thesis presents a new load balancing policy in
heterogeneous distributed systems. All nodes in this system
connected in point-to-point may have different service rates,
and each node can serve not only external arrival tasks but
also the tasks migrated from the oher nodes. The threshold
value we adopt is based on the ratio of service rates. The
scheduler takes into account the threshold value and the
current queue length in determining whether one task is
migrated to the other node or left for local node. Since each
node may be connected to several nodes and it has a threshold
value with respect to one of its adjacent slower or equal nodes
in service rate, each node may have multiple threshold values.
Thus, the policy we proposed is called the multiple threshold
load balancing policy. We use Markov process model to describe
the behavior of the heterogeneous distributed system with
multiple threshold policy. The model then is solved using the
Matrix-Geometric solution technique. Performance of the policy
is compared to that of the gereric load balancing policy, no
load balancing policy, and the ideal load balancing policy. We
conclude that our policy is better and close to the ideal load
balancing policy.
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Yang, Chih-Chiang, and 楊智強. "Dynamic Load Balancing in Distributed Heterogeneous Multi-Resource Servers." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/34233244815813182349.
Full textAbstract:
碩士<br>國立交通大學<br>資訊科學與工程研究所<br>96<br>Due to the progress of the Internet, there are more and more people using Internet services nowadays. In order to satisfy the huge service requirements, using multiple servers to provide different services at the same time is necessary. However, if we can’t effectively divide loads among servers, server utilization could decline and service quality could become uneven. Because of this reason, there are many researches have be presented to solve this problem. The load balancing methods can be roughly classified to four architectures: dispatcher-based, DNS-based, client-based and server-based, and different architectures have their own advantages and disadvantages. The conventional methods of load balancing always set a load buffer range to decrease the state change frequency of a service server in the geographic distributed load balancing architecture, and mostly assume that servers are homogeneous and just consider single resource consumption, such as CPU load. However, the load buffer range would result in load oscillation among servers. On the other hand, servers may not always have the same capacity, and jobs need many kinds of resource requirements. Only considering single resource consumption would cause the system bottleneck to derive from the lack of a small number of resources, and lead to low system utilization. For this reason, in the geographic distributed load balancing architecture, we use the concept of Random Early Detection (RED) to determine the server state probabilistically, and in the cluster load balancing architecture, we present a distributed market mechanism (MM) load balancing method which would consider the server heterogeneity and multiple-resource consumption simultaneously. In our simulation, we show that the oscillation of service server load can be reduced by using the concept of RED in the geographic distributed load balancing architecture. And distributed market mechanism load balancing method can improve the inter-server and intra-server load balancing at the same time, and keep the performance even if the server heterogeneity increasing, achieve high system utilization and low request response time.
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Lien, Feng-Wei, and 連峰偉. "A Load Balancing Algorithm on Heterogeneous Distributed WWW Servers." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/55082443192201576762.
Full textAbstract:
碩士<br>國立中正大學<br>資訊工程研究所<br>89<br>As the increasing of Web traffic, a distributed
multi-server website is needed to cope with growing client
demands. In this thesis we propose a load-balancing algorithm to
distribute client demands into several servers. The algorithm
dispatches web documents to heterogeneous servers. Each server
does not contain all documents and only allows to access the
local available documents. The aims of our algorithm are
two-fold: (1) to make load balancing as good as possible, and (2) to respond a easy request as soon as possible. If a user asks for a HTML file, he/she always expects the server response at once. But if a user asks for a CGI request, he/she will be aware of that a few waiting time is expected. When a server is busy handling with CGI requests, it may delay the response time of a HTML request. That's why we have the second aim of our algorithm. Our algorithm can produce a 15% performance improvement on load balancing and a 10% performance improvement on average response time.
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Wang, Sheng-Yuan, and 王聖淵. "Load Balancing Routing in Wireless Sensor Networks." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/93169751190161477681.
Full textAbstract:
碩士<br>國立臺北大學<br>資訊工程學系<br>102<br>Routing in WSN usually focuses on balanced distribution of nodes, nodes energy balanced and optimizing routing paths to be the shortest, fewer considering traffic load balancing issues. In WSN, some nodes become bottleneck because of encountering excessive data flow. So how to balance the load of network becomes the key of design WSN routing protocol. To achieve load balancing and reduce network bottleneck in data-intensive WSN, we propose Load Balancing Routing (LBR) protocol for WSN. LBR is based on layer routing design to connect sensor nodes and SINK. LBR contains Layering Route Construction ( LRC ), Load Estimation Algorithm ( LEA ), Smooth Transmission Mechanism ( STM ) and Route Maintenance ( RM ). LRC provides multiple next-hop choices from nodes to SINK and ensures each route is shortest that makes LBR scalable, low-overhead and robust. Through the cooperation of LRC and LEA, local and global load-balancing is accomplished. STM reduces a multi-node packets transmission at short time, which provides LBR better network transmission performance. When RM detects and recovers route failures, it does not broadcasts any error message to whole network, and can quickly adapt to network topology changes. RM makes LBR enhanced robustness route. Compared with AODV and AOMDV, simulation results show LBR provides better load balancing than AOMDV and AODV. LBR also achieves better network transmission performance and route maintenance.