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Unlu, Eren. "Dynamic Bandwidth allocation algorithms for an RF on-chip interconnect." Thesis, CentraleSupélec, 2016. http://www.theses.fr/2016SUPL0006/document.
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Avec l’augmentation du nombre de cœurs, les problèmes de congestion sont commencé avec les interconnexions conventionnelles. Afin de remédier à ces défis, WiNoCoD projet (Wired RF Network-on-Chip Reconfigurable-on-Demand) a été initié par le financement de l’Agence Nationale de Recherche (ANR). Ce travail de thèse contribue à WiNoCoD projet. Une structure de contrôleur de RF est proposé pour l’interconnexion OFDMA de WiNoCoD et plusieurs algorithmes d’allocation de bande passante efficaces (distribués et centralisés) sont développés, concernant les demandes et contraintes très spécifiques de l’environnement sur-puce. Un protocole innovante pour l’arbitrage des sous-porteuses pour des longueurs bimodales de paquets sur-puce, qui ne nécessite aucun signalisation supplémentaire est introduit. Utilisation des ordres de modulation élevés avec plus grande consommation d’énergie est évaluée<br>With rapidly increasing number of cores on a single chip, scalability problems have arised due to congestion and latency with conventional interconnects. In order to address these issues, WiNoCoD project (Wired RF Network-on-Chip Reconfigurable-on-Demand) has been initiated by the support of French National Research Agency (ANR). This thesis work contributes to WiNoCoD project. A special RF controller structure has been proposed for the OFDMA based wired RF interconnect of WiNoCoD. Based on this architecture, effective bandwidth allocation algorithms have been presented, concerning very specific requirements and constraints of on-chip environment. An innovative subcarrier allocation protocol for bimodal packet lengths of cache coherency traffic has been presented, which is proven to decrease average latency significantly. In addition to these, effective modulation order selection policies for this interconnect have been introduced, which seeks the optimal delay-power trade-off
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Fei, Ridong. "QoS-aware two-level dynamic bandwidth allocation algorithms in IEEE 802.16j-enabled vehicular networks." Thesis, University of Essex, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531555.
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Ou, Qi. "Bandwidth allocation algorithms for file distribution networks and location-aware topology construction in peer-to-peer networks /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20OU.
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Sen, Sanjoy Kumar. "Efficient Algorithms and Framework for Bandwidth Allocation, Quality-of-Service Provisioning and Location Management in Mobile Wireless Computing." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc278885/.
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The fusion of computers and communications has promised to herald the age of information super-highway over high speed communication networks where the ultimate goal is to enable a multitude of users at any place, access information from anywhere and at any time. This, in a nutshell, is the goal envisioned by the Personal Communication Services (PCS) and Xerox's ubiquitous computing. In view of the remarkable growth of the mobile communication users in the last few years, the radio frequency spectrum allocated by the FCC (Federal Communications Commission) to this service is still very limited and the usable bandwidth is by far much less than the expected demand, particularly in view of the emergence of the next generation wireless multimedia applications like video-on-demand, WWW browsing, traveler information systems etc. Proper management of available spectrum is necessary not only to accommodate these high bandwidth applications, but also to alleviate problems due to sudden explosion of traffic in so called hot cells.
In this dissertation, we have developed simple load balancing techniques to cope with the problem of tele-traffic overloads in one or more hot cells in the system. The objective is to ease out the high channel demand in hot cells by borrowing channels from suitable cold cells and by proper assignment (or, re-assignment) of the channels among the users. We also investigate possible ways of improving system capacity by rescheduling bandwidth in case of wireless multimedia traffic. In our proposed scheme, traffic using multiple channels releases one or more channels to increase the carried traffic or throughput in the system. Two orthogonal QoS parameters, called carried traffic and bandwidth degradation, are identified and a cost function describing the total revenue earned by the system from a bandwidth degradation and call admission policy, is formulated. A channel sharing scheme is proposed for co-existing real-time and non-real-time traffic and analyzed using a Markov modulated Poisson process (MMPP) based queueing model.
The location management problem in mobile computing deals with the problem of a combined management of location updates and paging in the network, both of which consume scarce network resources like bandwidth, CPU cycles etc. An easily implementable location update scheme is developed which considers per-user mobility pattern on top of the conventional location area based approach and computes an update strategy for each user by minimizing the average location management cost. The cost optimization problem is elegantly solved using a genetic algorithm.
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Rasmusson, Lars. "Network capacity sharing with QoS as a financial derivative pricing problem : algorithms and network." Doctoral thesis, SICS, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:ri:diva-22556.
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A design of an automatic network capacity markets, often referred to as a bandwidth market, is presented. Three topics are investigated. First, a network model is proposed. The proposed model is based upon a trisection of the participant roles into network users, network owners, and market middlemen. The network capacity is defined in a way that allows it to be traded, and to have a well defined price. The network devices are modeled as core nodes, access nodes, and border nodes. Requirements on these are given. It is shown how their functionalities can be implemented in a network. Second, a simulated capacity market is presented, and a statistical method for estimating the price dynamics in the market is proposed. A method for pricing network services based on shared capacity is proposed, in which the price of a service is equivalent to that of a financial derivative contract on a number of simple capacity shares.Third, protocols for the interaction between the participants are proposed. The market participants need to commit to contracts with an auditable protocol with a small overhead. The proposed protocol is based on a public key infrastructure and on known protocols for multi party contract signing. The proposed model allows network capacity to be traded in a manner that utilizes the network efficiently. A new feature of this market model, compared to other network capacity markets, is that the prices are not controlled by the network owners. It is the end-users who, by middlemen, trade capacity among each other. Therefore, financial, rather than control theoretic, methods are used for the pricing of capacity.
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Fan, Tianmin. "A novel dynamic bandwidth allocation algorithm with QoS support for EPON access networks." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27130.
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Ethernet passive optical network (EPON) has been considered as an attractive solution to next-generation broadband access networks due to its low cost and high throughput. However, designing efficient bandwidth allocation algorithms is a critical issue in EPON. In this thesis, various dynamic bandwidth allocation (DBA) algorithms for EPON systems are first reviewed. A novel DBA algorithm, called per-slot DBA (PSDBA), is then presented to efficiently and fairly allocate bandwidth among different users. The PSDBA algorithm is based on the multi-point control protocol (MPCP) and allocates bandwidth on a per-slot basis. It is also combined with non-strict priority scheduling and priority queuing to support differentiated services in the design of an EPON system.
Extensive simulation experiments are performed. Simulation results show that the PSDBA algorithm outperforms a well-known DBA algorithm using a per-frame bandwidth allocation strategy.
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Queiroz, Eduardo Martinelli Galvão de. "Algoritmo de alocação dinâmica de largura de faixa para redes de comunicação móvel celular." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-20062008-100444/.
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O crescente aumento da demanda de tráfego nas redes celulares vem aumentando a necessidade de uma melhor utilização dos recursos do sistema, já que sua expansão é custosa. Nas estações rádio base (ERB), a disponibilidade de largura de faixa de freqüências é limitada e desta maneira, em uma rede de comunicação móvel celular, o controle de admissão de chamadas exerce grande influência no desempenho do sistema, pois determina a utilização de banda das ERBs e se uma determinada quantidade de recursos (banda) será alocado ou não para uma determinada chamada. O desempenho da rede pode ser atrelado a determinados parâmetros, como a probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de chamadas handoff e a utilização de banda da rede. Este trabalho propõe um controle de admissão de chamadas que, no atendimento de uma chamada, faz o empréstimo de banda de chamadas em andamento na célula no caso de banda insuficiente. O sistema adota um mecanismo heurístico que determina a banda disponível para novas chamadas conforme os valores de certos parâmetros do sistema. O empréstimo de banda é realizado em chamadas em andamento nas células até níveis mínimos estabelecidos para cada tipo de chamada, que se diferenciam pelas necessidades de banda de cada uma. O algoritmo foi aplicado às bandas e características de uma rede de terceira geração (3G), que possui chamadas de voz, videoconferência, interação multimídia, e-mail, downloads e transferência de arquivos e a uma rede GSM/GPRS (global system for mobile communications/ general packet radio service), que possui chamadas de voz e de dados. Os resultados mostram melhorias na probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de handoff e na utilização de banda do sistema.<br>The recent growth in traffic loads in cellular networks has seen the need for a better use of system resources as its expansion is expensive. In the base transceiver station (BTS), the bandwidth availability is limited. Thus, in cellular networks the call admission control greatly influences the system performance because it determines the bandwidth use of the BTSs and if an amount of resources will or will not be allocated to a call. The network performance can be evaluated by parameters such as blocking probability of new calls, dropping probability of handoff calls and bandwidth use. This work proposes a call admission control that carries out the bandwidth borrowing when a call arrives and there is not enough bandwidth. The system makes use of a heuristic mechanism that determines the available bandwidth for the new calls according to some parameter values of the system. The bandwidth borrowing is applied to the cell ongoing calls until the minimum levels for each type are met. The algorithm was applied to the bandwidths and characteristics of a third generation cellular network, which supports voice calls, videoconference, multimedia interaction, e-mails, downloads and file transfers. It was also applied to a GSM/GPRS (global system for mobile communications/ general packet radio service), which supports voice and data calls. The results show improvements in the blocking probability of new calls, dropping probability of handoff calls and in the bandwidth use of the system.
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Núñez, Benjamin. "Applying a router-based-distributed bandwidth allocation algorithm to dynamically implement traffic engineering over MPLS-based networks in order to increase the quality of service for non-elastic applications." Diss., Connect to online resource, 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:1435226.
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Uznanski, Przemyslaw. "Large scale platform : Instantiable models and algorithmic design of communication schemes." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00878837.
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The increasing popularity of Internet bandwidth-intensive applications prompts us to consider followingproblem: How to compute efficient collective communication schemes on large-scale platform?The issue of designing a collective communication in the context of a large scale distributed networkis a difficult and a multi-level problem. A lot of solutions have been extensively studied andproposed. But a new, comprehensive and systematic approach is required, that combines networkmodels and algorithmic design of solutions.In this work we advocate the use of models that are able to capture real-life network behavior,but also are simple enough that a mathematical analysis of their properties and the design of optimalalgorithms is achievable.First, we consider the problem of the measuring available bandwidth for a given point-topointconnection. We discuss how to obtain reliable datasets of bandwidth measurements usingPlanetLab platform, and we provide our own datasets together with the distributed software usedto obtain it. While those datasets are not a part of our model per se, they are necessary whenevaluating the performance of various network algorithms. Such datasets are common for latencyrelatedproblems, but very rare when dealing with bandwidth-related ones.Then, we advocate for a model that tries to accurately capture the capabilities of a network,named LastMile model. This model assumes that essentially the congestion happens at the edgesconnecting machines to the wide Internet. It has a natural consequence in a bandwidth predictionalgorithm based on this model. Using datasets described earlier, we prove that this algorithm is ableto predict with an accuracy comparable to best known network prediction algorithm (DistributedMatrix Factorization) available bandwidth between two given nodes. While we were unable toimprove upon DMF algorithm in the field of point-to-point prediction, we show that our algorithmhas a clear advantage coming from its simplicity, i.e. it naturally extends to the network predictionsunder congestion scenario (multiple connections sharing a bandwidth over a single link). We areactually able to show, using PlanetLab datasets, that LastMile prediction is better in such scenarios.In the third chapter, we propose new algorithms for solving the large scale broadcast problem.We assume that the network is modeled by the LastMile model. We show that under thisassumption, we are able to provide algorithms with provable, strong approximation ratios. Takingadvantage of the simplicity and elasticity of the model, we can even extend it, so that it captures theidea of connectivity artifacts, in our case firewalls preventing some nodes to communicate directlybetween each other. In the extended case we are also able to provide approximation algorithmswith provable performance.The chapters 1 to 3 form three successful steps of our program to develop from scratch amathematical network communication model, prove it experimentally, and show that it can beapplied to develop algorithms solving hard problems related to design of communication schemesin networks.In the chapter 4 we show how under different network cost models, using some simplifyingassumptions on the structure of network and queries, one can design very efficient communicationschemes using simple combinatorial techniques. This work is complementary to the previous chapter in the sense that previously when designing communication schemes, we assumed atomicityof connections, i.e. that we have no control over routing of simple connections. In chapter 4 weshow how to solve the problem of an efficient routing of network request, given that we know thetopology of the network. It shows the importance of instantiating the parameters and the structureof the network in the context of designing efficient communication schemes.
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Lourenço, André Luiz Ferraz. "Técnicas de proteção e restauração em redes ópticas elásticas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-28012016-080915/.
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As redes ópticas estão passando por mudanças significativas, impulsionadas pelo crescimento exponencial do tráfego, principalmente advindo de serviços multimídia e armazenamento em nuvem. Esta demanda exigirá aumento da capacidade da taxa de transmissão para padrões como 400 Gb/s e 1 Tb/s. Nesse contexto, foi proposta uma arquitetura de rede com grade de frequências granular flexível chamada elastic optical network (EON). A EON divide o espectro de frequências em fatias (slots) de tamanho fixo e aloca grupos de slots contíguos estritamente de acordo com os requisitos de banda das demandas de conexão, implicando eficiência de uso do espectro. Com o aumento significativo da taxa de transmissão, acentuou-se a preocupação em manter a sobrevivência da rede, já que pouco tempo de queda no serviço pode acarretar uma imensa perda de dados. Neste trabalho, investigamos esquemas de proteção baseados em caminhos compartilhados (shared-path protection, SPP) e esquemas de restauração de tráfego. Avaliamos esquemas divulgados na literatura como o dynamic load balancing shared-path protection (DLBSPP) e esquemas de restauração como o traffic aware restoration (TAR) e bandwidth squeezed restoration (BSR). Avaliamos também uma heurística de alocação de slots chamada inverted dual stack (IDS). O DLBSPP utiliza balanceamento dinâmico de carga para computar os caminhos primários e de proteção compartilhados. O TAR executa a restauração dinâmica ordenando as conexões por granularidade de banda. O BSR utiliza a capacidade de contração de banda do EON para restaurar conexões por meio da política de melhor esforço ou de banda garantida, dependendo do acordo de níveis de serviço do cliente. O esquema IDS concentra o maior número possível de slots compartilhados em uma região do espectro. As medidas de desempenho dos algoritmos são avaliadas segundo as métricas: probabilidade de bloqueio, taxa de utilização do espectro, número médio de hops e taxa de restauração falha. As simulações computacionais mostram o bom desempenho da utilização do esquema IDS com DLBSPP.<br>Optical networks are undergoing significant changes driven by the exponentially growing traffic, especially coming from multimedia and cloud storage services. This demand will require increasing of the transmission rate capacity as high as 400 Gb/s and 1 Tb/s. Within this context, it was proposed the elastic optical network (EON), which is a network architecture with flexible granular frequency grid. EON divides the frequency spectrum into slices (slots) of fixed size and allocates groups of contiguous slots strictly according to the bandwidth requirement of the connection demands, providing high spectrum use efficiency. The significant increase in transmission rate put emphasis on the need to maintain the survival of the network, since the occurrence of faults in the network nodes or links can cause huge loss of data. In this work, we investigate protection schemes based on shared-path protection (SPP) and traffic restoration schemes. We evaluate schemes related in the literature, such as the dynamic load balancing shared-path protection (DLBSPP), and restoration schemes such as the traffic aware restoration (TAR) and the bandwidth squeezed restoration (BSR). The DLBP scheme uses dynamic load balancing to compute primary and shared protection paths. The TAR performs dynamic restoration ordering the connections based on band granularity. The BSR uses EON\'s band squeezing feature to restore connections by means of the best effort or guaranteed bandwidth strategy, depending on the customer\'s service level agreement. IDS scheme concentrates the maximum possible number of shared slots in a given region of the spectrum. Performance of the algorithms are evaluated according to metrics: blocking probability, spectrum utilization rate, average number of hops and failure restoration rate. Computer simulations show that the use of the IDS scheme improves the performance of the investigated algorithms.
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"Analytical Approach to Dynamic Bandwidth Allocation Algorithms used in LRPON." Master's thesis, 2012. http://hdl.handle.net/2286/R.I.15083.
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abstract: With internet traffic being bursty in nature, Dynamic Bandwidth Allocation(DBA) Algorithms have always been very important for any broadband access network to utilize the available bandwidth effciently. It is no different for Passive Optical Networks(PON), which are networks based on fiber optics in the physical layer of TCP/IP stack or OSI model, which in turn increases the bandwidth in the upper layers. The work in this thesis covers general description of basic DBA Schemes and mathematical derivations that have been established in research. We introduce a Novel Survey Topology that classifes DBA schemes based on their functionality. The novel perspective of classification will be useful in determining which scheme will best suit consumer's needs. We classify DBA as Direct, Intelligent and Predictive back on its computation method and we are able to qualitatively describe their delay and throughput bounds. Also we describe a recently developed DBA Scheme, Multi-thread polling(MTP) used in LRPON and describes the different viewpoints and issues and consequently introduce a novel technique Parallel Polling that overcomes most of issues faced in MTP and that promises better delay performance for LRPON.<br>Dissertation/Thesis<br>M.S. Electrical Engineering 2012
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Chen, Yen-Hung, and 陳彥宏. "Two-Dimensional Bandwidth Allocation Algorithms in IEEE 802.16 OFDMA System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/57479491232345701048.
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博士<br>國立臺灣科技大學<br>資訊管理系<br>101<br>Several two-dimensional bandwidth allocation algorithms in IEEE 802.16 OFDMA system were proposed. These algorithms, however, did not meet the bandwidth allocation specification described in the IEEE 802.16 standards, and they therefore suffer inferior throughput or are furthermore inappropriate to be applied. This thesis therefore proposes two heuristic algorithms, Best Corner Oriented (BCO) and Best Block Oriented (BBO), to comply with the IEEE 802.16 specification and provide high throughput in IEEE 802.16 networks considering the external fragmentation, internal fragmentation, and subchannel diversity. BCO mainly intends to avoid external fragmentation by constructing each burst from one of the two ending slots of the free bandwidth area to ensure that all free slots are within a continuous area. BBO mainly intends to use a better modulation coding scheme (MCS), that is, it places each burst in its best quality subchannels to adopt a better MCS. To avoid internal fragmentation, both BCO and BBO shrink the area measurement of the burst if the requested bandwidth is satisfied, so that unused slots internal to this burst can be used by other bursts. The simulation results under a heavy load indicate that BBO and BCO achieve 2 and 1.5 times, respectively, the throughput achieved by the conventional algorithm in the uplink. For the downlink, both algorithms achieve 9 times the throughput achieved by the conventional algorithm. Notably, the superior performance of BBO, comparing with that of BCO, is achieved at the expense of increased time complexity.
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Chang, Yu-Jen, and 張郁仁. "Flow Control and Bandwidth Allocation Algorithms for LTE-Advanced Relay Networks." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/493k37.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>99<br>Relay network is one of the candidates for extending coverage or enhancing throughput of the next generation cellular systems. In LTE-A relay networks, the based station (BS) does not know the channel quality of each mobile station (MS) served by its subordinate relay nodes (RNs). At the RN, the queues reserved for its serving MSs may have buffer overflow and/or buffer underflow problems due to the mismatch of the data rates between the access link and the relay link. In this paper, an analytical model is presented to derive the buffer-overflow and buffer-underflow probabilities for MSs served by an RN. Several flow control and bandwidth allocation algorithms are then proposed to deal with the buffer overflow/underflow problems. Simulation is then conducted to verify the accuracy of the analytical model and the effectiveness of the proposed algorithms.
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Chih-Cheng, Lo. "Studies of Contention Resolution and Bandwidth Allocation Algorithms over DOCSIS HFC Networks." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0005-0702200712422200.
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Chiu, Tsung-Pin, and 邱崇斌. "A Study of Dynamic Bandwidth Allocation Algorithms In Ethernet Passive Optical Networks." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/49125764665894802055.
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碩士<br>國立高雄第一科技大學<br>電腦與通訊工程所<br>94<br>Abstract
Ethernet passive optical networks, with low-cost and high-speed, are one of
the best solutions to solve the bottleneck problem in the broadband access
network. A major characteristic of Ethernet Passive Optical Network is the
shared upstream channel among end users, mandating efficient medium access
control to facilitate statistical multiplexing and provision multiple services for
different types of traffic.
Yuanqiu and Nirwan Ansari ( 2005 ) presented the upstream bandwidth
allocation algorithm,namely Dynamic Bandwidth Allocation with Multipleservice
(DBAM).It is quite suitable for heavy traffic multiservice access,since its
prediction traffic algorithm is based on the idea of『the waiter ,the more』, It may
not work well under the condition of light traffic in the upstream .
I II
In this work, we propose the Feedback Dynamic Bandwidth Allocation
(FDBA) to be aimed at upstream bandwidth allocation for any traffic multiservice
access. It bases burst traffic feedback prediction.
The simulation results show that our algorithm enhances QoS metrics such
as average frame delay, average queue length, and frame loss probability in
comparison to other existing algorithms.
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Lo, Chih-Cheng, and 羅志成. "Studies of Contention Resolution and Bandwidth Allocation Algorithms over DOCSIS HFC Networks." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/98235789959012923861.
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博士<br>國立中興大學<br>資訊科學系所<br>95<br>As broadband multimedia services becoming popular in the past few years, several emerging wired and wireless advanced access technologies have been studied to provide broadband access to subscribers. The Community Antenna Television (CATV) networks have become ubiquitous. Instead of constructing an entirely new broadband network infrastructure, the CATV network has emerged as one of the rapid and economic technologies to converge heterogeneous networks to provide broadband access to subscribers. The HFC network possesses a tree-and-branch architecture and highly asymmetric bandwidth, the upstream bandwidth is rarely and deeply influences the CATV network operation. How to support real-time multimedia applications, especially in an environment with heavy traffic, is a critical issue in modern CATV networks.
In this thesis, we propose to improve the upstream bandwidth allocation, contention resolution algorithm, and availability of DOCSIS HFC networks to fulfill the needs of real-time multimedia services. We first propose a Predictive Slot Allocation with Dynamic Contention Resolution Algorithm to predict the number of contention slots in order to better cope with the request contention problem and achieve better overall system performance. It is composed of two mechanisms: Adaptive Contention Slots with Statistics Control Algorithm to improve upstream throughput and Predictive P-Persistent with Dynamic Back-off Algorithm to decrease access delay.
To avoid the inherently unpredictable access delay of truncated binary exponential back-off algorithm adopted in DOCSIS, we propose a novel scheme named Adaptive Fast Expansion, Loading Statistics with Dynamic Swapping Algorithm to support real-time interactive services over HFC networks. It consists of two sub-algorithms: Adaptive Fast Expansion with Coordinate Centralized Control Algorithm, and Loading Statistics with Dynamic Swapping Algorithm. In addition to access delay and performance, as HFC networks is to become an infrastructure of broadband service networks, another important issue is the ability of the MAC layer to recover from service breakdown. Finally, we propose a Priority Ranging Scheme, to minimize service disruption time due to a large area malfunction, to enhance availability of DOCSIS HFC networks. Through simulation results, the proposed algorithms have been shown to perform better than that of the MCNS DOCSIS.
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Lin, Zhong-Xuan, and 林忠玄. "A Study of Class-Based Bandwidth Allocation Algorithms In Ethernet Passive Optical Networks." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/85107067963908179700.
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碩士<br>國立高雄第一科技大學<br>電腦與通訊工程所<br>95<br>Abstract
Ethernet passive optical networks, low-cost and high-speed, are one of the best solutions to the bottleneck problem of the broadband access network. A major characteristic of EPON is the shared upstream channel among end users, mandating efficient medium access control to facilitate statistical multiplexing and provision multiple services for different types of traffic.
Shengming Jiang and Yuming Jiang ( 2004 ) presented A Class-Based Bandwidth Allocation Scheme For EPONs . It allow EPON to use a dynamic weight priority scheduling(DWPS) for allocation upstream channel traffic and Strengthen the quality of services. It not only guarantees all ONUs fairly share the bandwidth of upstream on demand, but also supports differentiated services. To prevent one service class from monopolizing the bandwidth under heavy load.
In this study, we propose a new Class-Based Dynamic Bandwidth Allocation algorithm. It use the end user''s bandwidth demand to dynamic adjust bandwidth allocation. Revise the traffic immediately, in order to reach the characteristic of the high-quality service.
The simulation results show that our algorithm enhances QoS metrics such as average frame delay , and frame loss probability over other existing algorithms.
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徐子凱. "Toward Parallel Dynamic Bandwidth Allocation for Next-Generation OFDMA-PON using Multi-Objective Genetic Algorithms." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/62502012411513166281.
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碩士<br>國立交通大學<br>電信工程研究所<br>99<br>In this thesis, we propose a optimal, fast dynamic bandwidth allocation (DBA) for Next-Generation OFDMA-PON, which has high bandwidth, low-cost, energy- saving advantages and compatible with wireless signals. Our purpose is to monitor network traffic on-line and adjust bandwidth allocation to achieve high throughput and fairness to ensure quality of service (QoS). Multi-objective genetic algorithm (MOGA) is used to achieve optimization and transform complex bandwidth allocation mechanism into a more easily understanding and handled problem. Message Passing Interface (MPI) is now frequently used and we use it to expedite the processing of parallel computing speed. We expect a perfect combination of several methods to provide users the next generation optical network architecture with optimal bandwidth allocation and quality of service.
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Niu, Di. "Demand Forecast, Resource Allocation and Pricing for Multimedia Delivery from the Cloud." Thesis, 2013. http://hdl.handle.net/1807/43681.
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Video traffic constitutes a major part of the Internet traffic nowadays. Yet most video delivery services remain best-effort, relying on server bandwidth over-provisioning to guarantee Quality of Service (QoS). Cloud computing is changing the way that video services are offered, enabling elastic and efficient resource allocation through auto-scaling. In this thesis, we propose a new framework of cloud workload management for multimedia delivery services, incorporating demand forecast, predictive resource allocation and quality assurance, as well as resource pricing as inter-dependent components. Based on the trace analysis of a production Video-on-Demand (VoD) system, we propose time-series techniques to predict video bandwidth demand from online monitoring, and determine bandwidth reservations from multiple data centers and the related load direction policy. We further study how such quality-guaranteed cloud services should be priced, in both a game theoretical model and an optimization model.Particularly, when multiple video providers coexist to use cloud resources, we use pricing to control resource allocation in order to maximize the aggregate network utility, which is a standard network utility maximization (NUM) problem with coupled objectives. We propose a novel class of iterative distributed solutions to such problems with a simple economic interpretation of pricing. The method proves to be more efficient than the conventional approach of dual decomposition and gradient methods for large-scale systems, both in theory and in trace-driven simulations.
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Lee, Chun-Chieh, and 李俊杰. "Optimization of Fair Bandwidth Allocation Algorithm：A QoS Scheduling Algorithm for IEEE 802.16 System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/87703107771317147012.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>96<br>In the standard of IEEE 802.16, the specifications are for accessing Broadband Wireless Access (BWA) technology to provide high speed Internet access and multimedia service. Also, the standard supports different classes of services to meet the QoS requirements of different users. However, it is not defined about scheduling different types of service flow in the standard. Thus, in this paper, we propose a novel scheduling Algorithm for 802.16 BWA systems. This novel scheduling Algorithm is called Optimization of Fair Bandwidth Allocation (OFBA) Algorithm.
In OFBA Algorithm, different quota is provided to different class of traffic for each TDD frame (e.g. UGS, rtPS, nrtPS , BE ) for WiMax system. The allocated public bandwidth in one frame is called Public Quota which can be borrowed by all the classes. Each class cannot borrow a bandwidth over it is allowed. If part of the quota for one class is not used, it will be added to the public quota. If a class borrows from public quota in this round, it should return it to the public quota in the next round.
Eventually, Compare the OFBA with DFPQ Algorithm in 802.16 BWA systems. The simulation result can show that our proposed algorithm can achieve the system throughput is better and can observe system that average delay time and packet loss rate are reduced .
Key word：OFBA(Optimization of Fair Bandwidth Allocation)、Public Quota、DFPQ (Deficit Fair Priority Queue)、Throughput、Average delay time、Packet loss rate
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Qiu, J. "An adaptive dynamic bandwidth allocation algorithm for WiMAX/IEEE802.16 systems." 2006. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001963.
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M.Tech. Telecommunication Technology<br>Worldwide Interoperability for Microwave Access (WiMAX) will play an important role in the Fixed Broadband Wireless Access (FBWA) market since it is more cost-effective and faster to set up. WiMAX is a fixed Broadband Wireless Access system (BWA) based on the IEEE 802.16 standard.
The global demand for Internet access services has increased at a notable rate in recent years. The quality of service (QoS) of Voice over IP (VoIP) has become a crucial research topic. One of the challenges to achieve QoS requirements is to determine how to dynamically allocate system bandwidth to various applications.
The objective of this research is to propose an adaptive Dynamic Bandwidth Allocation (DBA) algorithm based on Priority Queuing (PQ) and Custom Queuing (CQ) and also its own soft-threshold feature for the downlink stream in WiMAX systems to achieve main QoS requirements for voice and data services. The proposed algorithm will be developed to achieve high system utilization and access control.
Through this research, it is shown that the proposed algorithm fulfils the main QoS requirements and fairness for different traffic. The performance comparisons through simulation experiments verify that the proposed algorithm achieves a high served traffic
ratio, high throughput and high bandwidth utilization. The adaptive algorithm is
configurable and may be optimised for specific traffic patterns.
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Huang, Jian-Hao, and 黃健豪. "Algorithm and Architecture Design of Bandwidth Allocation for Video Coding Applications." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/96348671840901787199.
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碩士<br>國立高雄第一科技大學<br>電腦與通訊工程研究所<br>105<br>As technology advances, image quality and resolution are getting higher and higher, relative to the video transmission to compress the amount of data is also more and more, in order to reduce the amount of data algorithm is also increasingly complex, the demand for the amount of bandwidth is also getting higher and higher, for real-time mobile video bandwidth is limited, so reducing the bandwidth usage is important.
So we proposed in the limited bandwidth, by referring to the size of the bit distortion rate cost (RDcost), to the bandwidth allocation and thus reduce the bandwidth to achieve the use, the experimental results show that our algorithm can save 17% ~ 29% memory bandwidth under acceptable bit rate and picture quality (PSNR).
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Chen, Wei-Ming, and 陳偉民. "Dynamic Bandwidth Allocation Using Enhanced Deficit Round Robin Algorithm for EPON." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/08989963026928925806.
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碩士<br>國立交通大學<br>電信工程研究所<br>98<br>Due to multimedia programs are increased and developed nowadays, the required bandwidth to many users is increased rapidly, too. The advantage of light is high transmission rate, low bit error rate, and extremely low signal attenuation. Therefore, optical network is the best choice to build next generation high speed network. In order to achieve dynamic bandwidth allocation and satisfy the demand for quality of service, the decrease in packet delay and delay variance are both the most important issues for us to improve.
In this article, we focus mainly on management of upstream traffic on EPON. The purpose of this algorithm is that bandwidth can be allocated fairly through adaptive modified the original. Furthermore, we also successfully decrease the mean packet delay and delay variance. A detailed description of the algorithm will be given in the text and the simulation result will show it can really achieve our requirements.
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Wu, Che-Wen, and 吳哲文. "Latency and Modulation Aware Dynamic Bandwidth Allocation Algorithm for WiMAX Base Stations." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/41259133525879975891.
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碩士<br>國立交通大學<br>網路工程研究所<br>95<br>The mobile WiMAX systems based on IEEE 802.16e-2005 provides high data rate for the mobile wireless network. However, the link quality is frequently unstable owing to the long-distance and air interference, leading to the crucible of real-time applications. Thus, a bandwidth allocation algorithm is required to satisfy (1) the latency requirement for real-time applications while supporting (2) service differentiation and (3) fairness. This work proposes the Highest Urgency First (HUF) algorithm to conquer the above challenges by taking into consideration the adaptive modulation and coding scheme (MCS) and the urgency of requests. This approach determines the downlink and uplink sub-frames by reserving the bandwidth for the most urgent requests and then proportionating the remaining bandwidth according to the non-urgent ones. Then, independently in the downlink and uplink, the HUF allocates bandwidth to every MS according to a pre-calculated U-factor which considers urgency, priority and fairness. The simulation results prove the HUF is modulation-aware and achieves the above three objectives, notably the zero violation rate within system capacity as well as the throughput paralleling to the best of the existing approaches.
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Cheng, Jyun-Yan, and 程鈞彥. "Multi-objective Bandwidth Allocation in Cognitive Wireless Mesh Networks Using Evolutionary Algorithm." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/24352984196795334429.
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Xu, Bo-Han, and 許博涵. "Bandwidth allocation according to queue length-a scheduling algorithm for WiMAX network." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/90599059452587471687.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>100<br>Worldwide Interoperability for Microwave Access (WiMAX) is a broadband
wireless access (BWA) technology. It provides high data rate and multimedia service.
WiMAX support Quality of Service (QoS) for various types of application. It is
important to allocate appropriate resource to different class of service to guarantee the
delay of real-time service and avoid the starvation of non-real-time service. In IEEE
802.16 standard for WiMAX network, this part is left opened to be explored.
The connection admission control (CAC) mechanism allows a connection to
reserve a bandwidth beforehand. Since a good prediction of the needed bandwidth is
not easy, a reserved bandwidth may not always be equal to the needed one.
Therefore, an algorithm adaptive to the load is proposed in this paper. A fixed
bandwidth is assigned to each connection in the first round according to the reserved
bandwidth. In the second round, two weight round robin algorithms are proposed.
In the first one, the weight is decided by the left queue length of the connection. In
the second one, the weight is decided by the left queue length and priority of the
connection. The second round will continue until the bandwidth of the frame is
exhausted or all packets in the queue have been scheduled. The simulation has been
done for theses two algorithms and compared with round robin algorithm. The result
shows these algorithms can adapt to the load of the connection for a fixed reserved
bandwidth.
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何斯瑜. "The Integration of Routing Algorithm and Bandwidth Allocation for Broadband Transfer Network." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/32624946653308945607.
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碩士<br>國立清華大學<br>工業工程與工程管理學系<br>91<br>Because of the change of the society-information-flow type and the coming of fast-transpotation era, the requirement of the network is steadily on the increase, and the one of the delivering speed and bandwidth also become higher and higher. But there is no infinite bandwidth to be provided to the traffic transmission. Therefore, how to use network most efficiently with limited resource is the main purpose. And most of type of traffics is multimedia now; that is the combination of sounds, images, data, pictures...etc. How to transfer to each node efficiently and quickly will be a big challenge.
To bring out the fastest traffic transmission, this research constructs the routing table to search routing quickly. Besides, on considering the calculation and location of bandwidth, and routing selection is separate in traditional way, but there will be such a weakness that it could just consider the individual optimization, not exactly the whole optimization. So this research considers two mechanisms together to reach the whole optimization. And it’s also going to simulate the actual process of traffic transmission by the simulation software, then to analysis the collected data to identify the feasibility, merit and shortcomings of the heuristic method in this research.
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Wu, Bo-Huei, and 吳柏輝. "Design of Low-Jitter Dynamic Bandwidth Allocation Algorithm in Ethernet Passive Optical Network." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/72259329215644805923.
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Chang, Yu-Ho, and 張友和. "Arrival Prediction Residue Bandwidth Allocation Algorithm: A QoS Control Protocol in 802.16 Network." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/10253979955029162453.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>97<br>In IEEE 802.16 system, the bandwidth is allocated by the Downlink & Uplink scheduler. All Subscriber Stations know when they should send or receive by DL_MAP and UP_MAP. For most existing schedulers, the bandwidth is allocated using the minimum reserved rate maximum sustained rate. If the allocated bandwidth of one queue has reached the maximum sustained rate, there will be no more bandwidth given to it. However, for some light loaded system, there may be some free slots left after the scheduler assigns slots to all packets in queue. Those packets arriving after the scheduling will wait until next frame although there are free slots available. So, we can allocate those free slots to these arriving packets beforehand.
For this, we propose a new allocation method in this thesis.
In this thesis, we divide the allocation work into three rounds. In the first round, the slots are allocated orderly based on maximal sustained rate of each queue. In the second round, the left slots are allocated by Round Robin. If there are free slots left in this frame, the packets in all service queues have been assigned slots after this round. Then, the third round can be continued. For this round, a method for forecasting the packet arrival rate is proposed. Then, the left slots are assigned according to the forecasted arrival rate of each queue. Comparing to other protocols, there is one more round in our protocol. Those packets sent by this round can be delivered almost one frame earlier. This can decrease the average delay of the network and improves its performance clearly.
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Chen, Hung-Yuan, and 陳鴻源. "Active Scheduling Algorithm for Intra-ONU Dynamic Bandwidth Allocation in Ethernet Passive Optical Networks." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19719649442951294115.
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碩士<br>國立成功大學<br>資訊工程學系碩博士班<br>96<br>Time-division multiple access scheme on a single wavelength is more attactive for upstream traffic in EPON. Each ONU doesn’t know start time of upstream bandwidth and granted window size each other, and it may cause conflicts. Considering upstream bandwidth utilization, packet delay and Quality-of-Service(QoS), it is very important to design an efficient bandwidth allocation algorithm conforming to requirement of QoS.
OLT and ONU communicate with each other by MPCP. We use inter-scheduling and intra-scheduling algorithms to manage bandwidth allocation for inter-ONU and intra-ONU, respectively. Each ONU sends REPORT message to OLT in their transmission window, and OLT executes inter-scheduling algorithm to calculate transmission window for receiving REPORT message from all ONUs.OLT sends a GATE message which contains start time and size of transmission window to each ONU. ONU used to decide the transmission order of queue data and the transmission size of queue data by executing intra-scheduling, we call it passive intra-scheduling.
The thesis focus on design of intra-scheduling algorithm, and we propose an active intra-scheduling algorithm. The general idea of active intra-scheduling algorithm is recording several queue sets in the reservation fields in REPORT message. We set thresholds for different classes to satisfy requirements of QoS. Therefore, OLT gets several sets of bandwidth requirement for receiving a REPORT message from one ONU. According to the bandwidth computed from inter-scheduling algorithm, OLT determines a appropriate allocation from queue sets in REPORT message. ONU gets granted window size based on REPORT which are send by ONU in previous cycle, so we call it active intra-scheduling algorithm.
Using active intra-scheduling also eliminate unused slotted remainder (USR), besides satisfying requirement of QoS and reasonable packet delay for different class. ONU can’t completely make use of upstream bandwidth which are given by OLT because ethernet packet is not divided, and it will cause USR which is from 0 to 1517bytes.
ONUs contrast granted window size in GATE message with REPORT which was sent to OLT, and it will find a queue set in which sum of queue report equal to granted window size. ONUs transmit packet according to the queue set which is found by contrasting in priority order. For this reason, ONU can completely eliminate USR.
We use the inter-scheduling which is mentioned in other reference and combine it with active intra-scheduling for enhancing throughput, satifying requirement of QoS, and reasonable packet delay.
Finally, we compare the proposed scheme with EAF scheduling in our simulation results. We simulate USR, throughput, packet delay for uniform and non-uniform load to prove our scheme better.
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Hsu, Ko-kuan, and 許克寬. "An Efficient Dynamic Bandwidth Allocation Algorithm with Two-Round Deliberation in Light Trail Networks." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/77088081093229866853.
Full textAbstract:
碩士<br>國立成功大學<br>資訊工程學系碩博士班<br>96<br>In recent years, because of the rapid advance of Dense WDM, each fiber link can provide hundreds of wavelengths and each wavelength can suffer huger bandwidth than before. The traditional solution of node communication for optical networks can not satisfy the explosive bandwidth and traffic demands anymore owing to the non-efficient allocation for the huge bandwidth. Light trail, a new proposed solution recently, is generalized from the light path and has advantages of bandwidth sharing and efficient bandwidth utilization. There are many researches discuss about the routing algorithm in the light trail networks. However, the better performance of light trail is caused by a good routing algorithm and an efficient dynamic bandwidth allocation scheme. In this thesis, we introduce an efficient dynamic bandwidth allocation scheme with double check mechanism, named Demand and Delay latency-aware with Two-round Evaluation (DDTE), to allocate bandwidth more accurately and efficiently in light trail networks. In addition to the bandwidth allocation scheme, we also propose a setup mechanism and a release scheme for the light trail networks.
For investigating the superiority of DDTE, we develop a simulation by using four topologies with four scenarios and compare DDTE with previously proposed Dual Auction algorithm. We can observe the obvious improvement in both of blocking rate and delay performance through the results of developed simulation. Although the more control packets should be used in DDTE to notify nodes to transmit data in their scheduled duration in one cycle, we can find it still in an acceptable range and the better cost-effective improvement will be achieved in ring-like networks.
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Chen, Yen-Hung, and 陳彥宏. "A Channel Quality and QoS Aware Bandwidth Allocation Algorithm for IEEE 802.16 Base Stations." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/53752j.
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碩士<br>國立臺灣科技大學<br>資訊管理系<br>95<br>In IEEE 802.16 networks, channel experiencing various modulations and packet loss percentiles form a multi-rate environment. Thus, an excellent bandwidth allocation algorithm should not only satisfy various QoS requirements of heterogeneous traffic, but also dispense more bandwidth to the connection with better channel quality for maximizing bandwidth utilization. However, to the best of our knowledge, there is no any work dedicated to this. In this thesis, a channel quality and QoS aware bandwidth allocation algorithm is proposed. This algorithm can not only satisfy each connection's QoS requirement, but also maximize bandwidth utilization by dynamically adjusting the DL/UL bandwidth ratio to match the current DL/UL traffic ratio and allocating more bandwidth to the connections with better channel quality. Simulation results demonstrate that our algorithm can more satisfy each connection's QoS requirement and provide higher bandwidth utilization, comparing with the previous algorithms.
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Lin, Fang-Ting, and 林芳廷. "Design of Leaky Bucket Based Admission Control and Dynamic Bandwidth Allocation Algorithm for WiMAX MAC." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/61078800825321815913.
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碩士<br>國立暨南國際大學<br>通訊工程研究所<br>96<br>The IEEE 802.16d claims to support high bandwidth for the wireless metropolitan area network. However, the standard does not propose including the method for bandwidth management. Therefore, a feasible bandwidth allocation algorithm will be very important.
The thesis proposes a Leaky Bucket based admission control algorithm and dynamic bandwidth algorithm for a WiMAX BS. For a new services flow, the admission control algorithm (CAC) will calculate the required bandwidth according to the Leaky Bucket parameters of the flow. Only if the total required bandwidth of all flows is smaller than the system capacity, the new flow can admitted. In the run time, the BS needs to allocate symbols to DL/UL subframes for every frame. In addition to the queue length, we also use the required bandwidth calculated by CAC as a parameter to allocate the bandwidth dynamically.
The proposed algorithm are implemented in the NS-2 simulator and verified by simulation. Compared to the fixed allocation scheme, our algorithm can provide quality of service and uses the bandwidth efficiency.
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Lin, Chen-Chin, and 林振欽. "Using Genetic Algorithm to Optimize Bandwidth Allocation with Delay Guaranteed for Third Generation Mobile Communication Systems." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/14479150612278476403.
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碩士<br>國立政治大學<br>資訊科學學系<br>91<br>Third Generation Mobile Communication Systems (3G) provide higher bandwidth to fulfill applications of multimedia. However transmission of multimedia not only needs bandwidth but also delay, jitter and packet loss guaranteed. In order to satisfy all QoS constraints and improve the system utilization, UMTS classify the traffic into four classes — conversational, streaming, interactive and background.
This thesis uses genetic algorithm to optimize bandwidth allocation. But the genetic algorithm is a time consuming algorithm. So we propose feedback genetic algorithm to speed up computation. On the other hand, we adopt the delay constraint function of WFQ to compute and guarantee delay time. With feedback genetic algorithm and delay constraint function, we can optimize bandwidth allocation with delay guaranteed. Besides, we also take users satisfactions and operators profit into consideration.
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Lee, Chun-Chieh, and 李俊杰. "Bandwidth Allocation Using the Mean & Standard deviation of Arrival Process:A Scheduling Algorithm for WiMAX Network." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/927884.
Full textAbstract:
博士<br>國立臺灣科技大學<br>電子工程系<br>104<br>Five types of service flows are defined in the standard of IEEE 802.16. Each service flow has its own type of quality of service (QoS) requirement. Some scheduling algorithm is needed to satisfy the QoS requirement of each class. Traditional Base Station allocates bandwidth according to the request of user. However, the request may not equal to the real requirement in some situation. Thus, the assignment of bandwidth may be far from the real requirement. When the load is heavy, this may cause the time delay of some queue too large and create serious problem for real time traffic. Also, this may make the CAC mechanism denies any service although some old grants are never used completely. A method named BAcSOA is proposed to solve this problem in this paper.
In the beginning, we will use the traditional “Request & Grant” mechanism. However, we will assume some users may not estimate their request correctly and the system may not operate efficiently. To correct it, the mean μ and standard deviation σ of the arrival rate for ertPS and rtPS traffic will be estimated during the operation of system. The mean μ represents the average requirement and the standard deviation σ includes the possibly temporary requirement of this queue. Therefore, the grant will be replaced and μ+kσ will be used as the assignment of these traffics. Larger k gives real-time traffic more chance to send all its data in the queue.
For real-time classes, the sent packet has a deadline. As the transmission delay is over the limitation of deadline, the packet becomes useless and will be discarded. Thus, they will be served earlier and have higher probability. The scheduler should assign proper bandwidth for real-time flows and send the real-time packets before they are discarded. To deicide the right allocated bandwidth, the arrival rate of each flow is a good parameter for assignment. The average μ and standard deviation σ of arrival rate correspond to the long term need and variation of load for one flow. Thus, we proposed μ+kσ is used as a reference to allocate bandwidth for one flow. Different classes of flows will be given different values of k which corresponds to the priorities of classes. In this algorithm, flow with higher priority should have larger value of k. The value of k will decide the performance of this class.
In this paper, we revise the algorithm to EBAcSOA and propose a mathematical way to decide the value of k for a required performance. Then, a simulation platform is proposed to decide k such that a required performance can be obtained for an operating system. This approach may be different from other researches in which there is no required performance and the performance results are obtained only for several operating points. However, the approach proposed is more practical from the view of an operator and may become an attractive point for other researchers.
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Wu, Yu Chiang, and 吳雨檣. "Design of Low Packet Delay Dynamic Bandwidth Allocation Algorithm in Next-Generation Ethernet Passive Optical Network." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/53765274850491050994.
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Chen, Cheng-yu, and 陳政隅. "Bandwidth Allocation according to Queue Length and packet loss rate - a scheduling algorithm for WiMAX network." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/46993299833005341947.
Full textAbstract:
碩士<br>國立臺灣科技大學<br>電子工程系<br>101<br>IEEE 802.16 is a broadband multimedia standard which supports five different service classes and satisfies QoS(Quality of Service) requirements for each class.
The real-time packets are constrained by timing. When the delay time of transmission is bigger than the maximum value, packets will be dropped. In this dissertation, we focus on the ertPStraffic in WiMAX network and set a constraint on its delay time.With thisconstraint, packet dropping happens when delay time of a packet is bigger than this value.Then, the bandwidth is scheduled according to the length of each queue.With simulation, packet loss ratesare found for different traffic loads.With the second method of bandwidth allocation according to queue length(BA-QL2), each class is assigned a weight β. The main purpose of this dissertationis to find this value for possible required loss rate. With our proposed algorithm, β can be found such that the loss rate can be as close to this required value as possible. In this dissertation, the proposed algorithm is simulated and tested. The simulated approach can be used as a templatefor anyone who wants to find an appropriate β for his model.
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Chien, Shih-Hsin, and 簡世昕. "Two-Phase Proportionating (TPP): A Combined Uplink and Downlink Bandwidth Allocation Algorithm for 802.16e-2005 MAC." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/11870822932991323832.
Full textAbstract:
碩士<br>國立交通大學<br>資訊科學與工程研究所<br>94<br>The IEEE 802.16e-2005 claims to support high bandwidth for the wireless metropolitan area network. However, the link quality is very likely to degrade due to the long-distance and unstable wireless link, bringing ordeals to the real-time applications. Therefore, a feasible bandwidth allocation algorithm is required to utilize the precious bandwidth and to provide service differentiation. This work proposes a Two-Phase Proportionating (TPP) algorithm to tackle the above challenges. Considering different slot sizes for the uplink and downlink whose ratio is 3:2, the first phase dynamically determines the subframe sizes according to the bandwidth requests from subscriber stations. The second phase further differentiates a service class along with a weight which denotes the accumulated maximum sustained rates and with a novel adjustment factor practically reflecting the bandwidth demand of the service class. The simulation results demonstrate that the TPP improves the bandwidth utilization by 20% compared to the static allocation, and the service differentiation are strictly guaranteed. Besides, the performance comparison with other schemes shows TPP has the highest bandwidth utilization and most differentiated for every service class.
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Hsu, Chiang-Hsuan, and 許獎玹. "Improvement of Fair End-to-end Bandwidth Allocation Algorithm in Multi-channel IEEE 802.16 Wireless Mesh Networks." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/21847478061966275048.
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碩士<br>義守大學<br>資訊工程學系碩士班<br>96<br>In the recent years, due to that it takes the advantages of high capacity, high transmission rate, low cost and extensive coverage, WMN(Wireless Mesh Network) was one of the most worthy technique. But WMN dot not perform well in every aspect, such as that it can not allocate bandwidth fairly to each end-to-end traffic flow. The FEBA algorithm was aimed to solve the problem on end-to-end transmission in IEEE 802.16. However, the packet scheduling algorithm DRR may result in higher delay time of short packet. We introduce anther packet scheduling algorithm DDRR to solve such problem in WMN. Finally, we used the NS2 to be simulation platform, and the simulation results show that the FEBA with DDRR has better end-to-end delay than that of FEBA with DRR.
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Chen, Chen-Fu, and 陳建甫. "Joint Relay Selection, Bandwidth Allocation and Power Distribution via Genetic Algorithm in Decode-and-Forward Relay Networks." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/94296245882308925310.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>100<br>Cooperative networks are an emerging transmission technique in
which a distributed antenna array can be created and provide the
spatial diversity gains by relaying each other’s messages to the des-
tination. It is well known that the performance of a cooperative
network can be enhanced by appropriate resource allocation based
on the channel state information.
To attain superior performance for the downlink of cooperative
multi-user decode-and-forward (DF) systems, in this thesis we con-
sider to take some crucial issues in the resource allocation, such as
relay selection, bandwidth allocation, and power distribution, into
consideration as a whole. We first determine an upper bound for
the highly optimization problem considered by ignoring some con-
straints. Thereafter, to resolve this nonlinear optimization problem,
we also propose a genetic approach for joint relay subset selection,
bandwidth allocation and power distribution. To accommodate this
joint consideration, each chromosome in the proposed genetic algo-
rithm (GA) is divided into an integer string for relay selection and
two real number strings for bandwidth allocation and power dis-
tribution. In addition, new crossover and mutation operations are employed for this new type of chromosome. Conducted simulations
show that the proposed GA-based approach can attain close per-
formance as the upper bound and outperforms some representative
previous works.
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Chan, Chih-Chia, and 詹志嘉. "The study of upstream bandwidth allocation algorithm with QoS guarantee in the DOCSIS standard over HFC networks." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/09166411316975726668.
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碩士<br>國立中興大學<br>資訊科學系所<br>94<br>Voice over IP (VoIP) is one of the most important topics on the information and communication technologies. Many companies have deployed to VoIP for cost saving. Providing good voice quality of communication is the first priority issue especially in hybrid fiber/coax (HFC) network. Quality of Service (QoS) guarantee in such an environment.
In this thesis, we first introduce the issues of upstream bandwidth allocation in the current HFC network. We propose a UBAS (The upstream bandwidth allocation scheduler) scheme to deal with upstream bandwidth allocation with QoS guarantee. Finally, through simulations, we prove that using UBAS scheme can lower transmission delay and effectively improve the quality of VoIP.