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## Alocação dinâmica de largura de banda em redes EPON; Dynamic bandwidth allocation for EPON networks

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Dissertação de Mestrado
Formato: application/pdf

Publicado em 10/08/2007
PT

Relevância na Pesquisa

76.54%

#Access networks#Alocação dinâmica de largura de banda#Classes de serviço#Classes of service#Dynamic bandwidth allocation#EPON#EPON#Ethernet#Ethernet#Fibra óptica#Multiplexação estatística

As redes de telecomunicações se dividem em redes de longa distância, redes metropolitanas e redes de acesso. As redes de longa distância e metropolitana usufruem a alta capacidade de largura de banda da fibra óptica, enquanto nas redes de acesso há um gargalo de largura de banda por causa do uso de pares de fios e cabo coaxial. Para solucionar este problema e oferecer aos usuários acesso banda larga de baixo custo foram propostas as redes ópticas passivas (passive optical network - PON). A PON é formada por dois elementos básicos, a unidade de rede óptica (optical network unit - ONU), localizada perto dos assinantes, e o terminal de linha óptica (optical line terminal - OLT), localizado próximo ao provedor de serviços. Dentre os padrões disponíveis para redes PON, o Ethernet (EPON), padronizado pelo grupo IEEE 802.3ah, é opção atraente porque ele é bastante difundido nas redes locais. O protocolo de controle multiponto (multipoint control protocol - MPCP), já especificado, é responsável pelo controle de acesso ao meio, fornecendo infra-estrutura de sinalização para transmissão entre OLT e ONUs. Entretanto, o algoritmo de alocação de largura de banda, que realiza o controle de acesso ao meio com base no MPCP...

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## Algoritmo de alocação dinâmica de largura de faixa para redes de comunicação móvel celular; Dynamic bandwidth allocation algorithm for mobile communication networks

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Dissertação de Mestrado
Formato: application/pdf

Publicado em 28/03/2008
PT

Relevância na Pesquisa

66.28%

#Algoritmos de alocação de banda#Bandwidth allocation algorithms#Call admission control#Controle de admissão de chamadas#GSM/GPRS networks#Mobile cellular communication networks#Redes de comunicação móvel celular#Redes de terceira geração (3G)#Redes GSM/GPRS#Third generation cellular networks (3G)

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...

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## Algoritmos para alocação de banda em redes de acesso GPON; Algorithms for bandwidth allocation in GPON access networks

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Dissertação de Mestrado
Formato: application/pdf

Publicado em 26/02/2010
PT

Relevância na Pesquisa

66.53%

#Acesso Múltiplo por Divisão de Tempo (TDMA)#Alocação dinâmica de banda#Comunicação óptica#Dynamic bandwidth assignment#Gigabit PON (GPON)#Gigabit PON (GPON)#Optical communication#Passive Optical Network (PON)#Passive Optical Network (PON)#Time Division Multiple Access (TDMA)

Neste trabalho propomos e analisamos algoritmos de alocação dinâmica de banda para rede óptica passiva (PON) de acesso padrão GPON (Gigabit PON). Estes algoritmos utilizam dados oriundos de SLA (service level agreement) para gerenciar a alocação de banda e classificar em 4 contêineres de tráfego (T-CONT) o tráfego gerado em 16 ONUs (optical network unit). Na transmissão upstream é utilizada a técnica de multiplexação por divisão de tempo (TDM) para gerenciar o acesso ao meio, evitando colisões. O primeiro algoritmo proposto aloca banda garantida para as ONUs e distribui a banda não utilizada de acordo com critério baseado em três SLAs. A taxa de bit upstream é 1,25 Gbps e o desempenho do algoritmo é analisado com base na variação do atraso de pacotes em função do tráfego gerado nas ONUs. O segundo algoritmo proposto utiliza ponderação de tráfego. Neste, analisamos o comportamento dos atrasos e a quantidade de banda solicitada e atendida por ONU quando as bandas garantida e extra são alteradas. Por fim, acrescentamos em nossa implementação um intervalo para o processamento do algoritmo de alocação dinâmica de banda (DBA) e resposta do hardware relacionado ao ciclo de interrogação. Então, analisamos o atraso de pacotes quando variamos o intervalo de processamento do DBA. Ao final...

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## Differential bandwidth allocation with multiplexed TCP connections

Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology

Tipo: Tese de Doutorado
Formato: 66 p.; 3876583 bytes; 3882882 bytes; application/pdf; application/pdf

EN_US

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This thesis presents and evaluates the design and implementation of a user-level library that performs bandwidth allocation among multiple application flows using multiple TCP connections. This work is motivated by emerging trends in network overlay applications to send multiple flows of data between machines. Existing approaches to manage the network either do not offer the control over network resources that these applications need, or are difficult to adopt. We present a novel user-level approach to this problem that uses multiple TCP connections, and we also present an evaluation of multiplexing strategies for the scheduler that multiplexes the multiple application flows onto the multiple TCP connections. We implemented and designed two scheduling algorithms, striping and pinning, to perform the multiplexing and evaluated them for various application behavior and various link characteristics through emulation. We describe how striping is preferred for applications that are not delay dependent, as well as applications that are not order dependent, while pinning is preferred for applications that are heavily memory constrained. Our results show that, for delay-constrained applications, links with low loss and low number of cross traffic favor the striping scheduler...

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## Efficient asynchronous scheduling algorithms for cost-effective buffered crossbar switches

Fonte: FIU Digital Commons
Publicador: FIU Digital Commons

Tipo: Artigo de Revista Científica

EN

Relevância na Pesquisa

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Buffered crossbar switches have recently attracted considerable attention as the next generation of high speed interconnects. They are a special type of crossbar switches with an exclusive buffer at each crosspoint of the crossbar. They demonstrate unique advantages over traditional unbuffered crossbar switches, such as high throughput, low latency, and asynchronous packet scheduling. However, since crosspoint buffers are expensive on-chip memories, it is desired that each crosspoint has only a small buffer.^ This dissertation proposes a series of practical algorithms and techniques for efficient packet scheduling for buffered crossbar switches. To reduce the hardware cost of such switches and make them scalable, we considered partially buffered crossbars, whose crosspoint buffers can be of an arbitrarily small size. Firstly, we introduced a hybrid scheme called Packet-mode Asynchronous Scheduling Algorithm (PASA) to schedule best effort traffic. PASA combines the features of both distributed and centralized scheduling algorithms and can directly handle variable length packets without Segmentation And Reassembly (SAR). We showed by theoretical analysis that it achieves 100% throughput for any admissible traffic in a crossbar with a speedup of two. Moreover...

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## Bandwidth allocation for quality of service provision in IEEE 802.16 systems.

Fonte: Universidade de Adelaide
Publicador: Universidade de Adelaide

Tipo: Tese de Doutorado

Publicado em //2009

Relevância na Pesquisa

46.09%

This thesis investigates various aspects of bandwidth allocation and scheduling in the Medium Access Control (MAC) layer of IEEE 802.16 systems. We highlight the important aspects of designing a scheduler and describe the scheduler design problem from a general perspective. That is, we provide a scheduler design framework driven by a set of objectives defined for the systems. In addition, we include Subscriber Station differentiation into our scheduler design. This approach is comprehensive, as it covers the requirements of both the network provider and the end users.
In developing the framework, we discuss the importance of achieving customer satisfaction. This leads to an interesting objective that maximises the number of satisfied customers, rather than network centric objectives, such as fairness. We contend that providing fairness to customers does not necessarily achieve the best outcome for customer satisfaction and artificially limits the choices available to service providers.
In order to maximise the number of satisfied customers, we analyse in detail the Dual-Queue (DQ) scheduling discipline proposed by Hayes et al. [2]. The DQ algorithms of Hayes’ work are focused on wireline networks, and are not directly deployable in an 802.16 environment...

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## Dynamic Bit Allocation for Object Tracking in Bandwidth Limited Sensor Networks

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 21/10/2011

Relevância na Pesquisa

36.36%

In this paper, we study the target tracking problem in wireless sensor
networks (WSNs) using quantized sensor measurements under limited bandwidth
availability. At each time step of tracking, the available bandwidth $R$ needs
to be distributed among the $N$ sensors in the WSN for the next time step. The
optimal solution for the bandwidth allocation problem can be obtained by using
a combinatorial search which may become computationally prohibitive for large
$N$ and $R$. Therefore, we develop two new computationally efficient suboptimal
bandwidth distribution algorithms which are based on convex relaxation and
approximate dynamic programming (A-DP). We compare the mean squared error (MSE)
and computational complexity performances of convex relaxation and A-DP with
other existing suboptimal bandwidth distribution schemes based on generalized
Breiman, Friedman, Olshen, and Stone (GBFOS) algorithm and greedy search.
Simulation results show that, A-DP, convex optimization and GBFOS yield similar
MSE performance, which is very close to that based on the optimal exhaustive
search approach and they outperform greedy search and nearest neighbor based
bandwidth allocation approaches significantly. Computationally, A-DP is more
efficient than the bandwidth allocation schemes based on convex relaxation and
GBFOS...

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## Joint Downlink Cell Association and Bandwidth Allocation for Wireless Backhauling in Two-Tier HetNets with Large-Scale Antenna Arrays

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 31/12/2014

Relevância na Pesquisa

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The problem of joint downlink cell association (CA) and wireless backhaul
bandwidth allocation (WBBA) in two-tier cellular heterogeneous networks
(HetNets) is considered. Large-scale antenna array is implemented at the macro
base station (BS), while the small cells within the macro cell range are
single-antenna BSs and they rely on over-the-air links to the macro BS for
backhauling. A sum logarithmic user rate maximization problem is investigated
considering wireless backhauling constraints. A duplex and spectrum sharing
scheme based on co-channel reverse time-division duplex (TDD) and dynamic soft
frequency reuse (SFR) is proposed for interference management in two-tier
HetNets with large-scale antenna arrays at the macro BS and wireless
backhauling for small cells. Two in-band WBBA scenarios, namely, unified
bandwidth allocation and per-small-cell bandwidth allocation scenarios, are
investigated for joint CA-WBBA in the HetNet. A two-level hierarchical
decomposition method for relaxed optimization is employed to solve the
mixed-integer nonlinear program (MINLP). Solutions based on the General
Algorithm Modeling System (GAMS) optimization solver and fast heuristics are
also proposed for cell association in the per-small-cell WBBA scenario. It is
shown that when all small cells have to use in-band wireless backhaul...

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## A Study on Impacts of RTT Inaccuracy on Dynamic Bandwidth Allocation in PON and Solution

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 12/10/2014

Relevância na Pesquisa

56.47%

The circle travelling delay between OLT (Optical Line Terminal) and ONU
(Optical Network Unit) is one of most important items in dynamic bandwidth
allocation (DBA) algorithms in PON, called RTT (Round Trip Time). The RTT is
taken into account when OLT assigns the start times for upstream bandwidth
grants. In most case, RTT is estimated before making bandwidth allocation
decisions in dynamic bandwidth allocation algorithms. If the estimated RTT is
incorrect, the bandwidth allocation decisions are not matched with bandwidth
requests of channels. Thus, performance of PON can get worse by deviation of
RTT. There are several reasons that cause the RTT to be varying, such as
processing delay, distance of OLT and ONU, changing in fiber refractive index
resulting from temperature drift, and degree of accuracy of RTT estimation
methods. In this paper, we evaluate the impacts of RTT inaccuracy on
performance of DBA and identify levels of collision and waste of bandwidth. By
this way, we propose a method to remedy the performance degradation encountered
by the situation; Comment: 10 pages, 4 figures, IJCNC

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## Efficient Upload Bandwidth Estimation and Communication Resource Allocation Techniques

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 09/01/2010

Relevância na Pesquisa

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#Computer Science - Networking and Internet Architecture#Computer Science - Distributed, Parallel, and Cluster Computing#Computer Science - Data Structures and Algorithms#C.2.1#C.2.2#C.2.4#G.2.1#G.2.2

In this paper we address two problems, for which we present novel, efficient,
algorithmic solutions. The first problem is motivated by practical situations
and is concerned with the efficient estimation of the upload bandwidth of a
machine, particularly in the context of a peer-to-peer content sharing and
distribution application. The second problem is more of a theoretical nature
and considers a constrained communication resource allocation situation.; Comment: Proceedings of the 9th WSEAS International Conference on Multimedia,
Internet & Video Technologies (MIV), Budapest, Hungary, 3-5 September, 2009;
ISBN: 978-960-474-114-4 / ISSN: 1790-5109

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## Radio Resource Allocation Algorithms for Multi-Service OFDMA Networks: The Uniform Power Loading Scenario

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 15/11/2012

Relevância na Pesquisa

36.23%

Adaptive Radio Resource Allocation is essential for guaranteeing high
bandwidth and power utilization as well as satisfying heterogeneous
Quality-of-Service requests regarding next generation broadband multicarrier
wireless access networks like LTE and Mobile WiMAX. A downlink OFDMA
single-cell scenario is considered where heterogeneous Constant-Bit-Rate and
Best-Effort QoS profiles coexist and the power is uniformly spread over the
system bandwidth utilizing a Uniform Power Loading (UPL) scenario. We express
this particular QoS provision scenario in mathematical terms, as a variation of
the well-known generalized assignment problem answered in the combinatorial
optimization field. Based on this concept, we propose two heuristic search
algorithms for dynamically allocating subchannels to the competing QoS classes
and users which are executed under polynomially-bounded cost. We also propose
an Integer Linear Programming model for optimally solving and acquiring a
performance upper bound for the same problem at reasonable yet high execution
times. Through extensive simulation results we show that the proposed
algorithms exhibit high close-to-optimal performance, thus comprising
attractive candidates for implementation in modern OFDMA-based systems.; Comment: accepted for publication at the Springer Telecommunication Systems
Journal (TSMJ)

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## Multiuser Joint Energy-Bandwidth Allocation with Energy Harvesting - Part I: Optimum Algorithm & Multiple Point-to-Point Channels

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 10/10/2014

Relevância na Pesquisa

56.4%

In this paper, we develop optimal energy-bandwidth allocation algorithms in
fading channels for multiple energy harvesting transmitters, each may
communicate with multiple receivers via orthogonal channels. We first assume
that the side information of both the channel states and the energy harvesting
states is known for $K$ time slots {\em a priori}, and the battery capacity and
the maximum transmission power in each time slot are bounded. The objective is
to maximize the weighted sum-rate of all transmitters over the $K$ time slots
by assigning the transmission power and bandwidth for each transmitter in each
slot. The problem is formulated as a convex optimization problem with ${\cal
O}(MK)$ constraints, where $M$ is the number of the receivers, making it hard
to solve with a generic convex solver. An iterative algorithm is proposed that
alternatively solves two subproblems in each iteration. The convergence and the
optimality of this algorithm are also shown. We then consider the special case
that each transmitter only communicates with one receiver and the objective is
to maximize the total throughput. We develop efficient algorithms for solving
the two subproblems and the optimal energy-bandwidth allocation can be obtained
with an overall complexity of ${\cal O}(MK^2)$. Moreover...

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## Multiuser Joint Energy-Bandwidth Allocation with Energy Harvesting - Part II: Multiple Broadcast Channels & Proportional Fairness

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 10/10/2014

Relevância na Pesquisa

46.36%

In this paper, we consider the energy-bandwidth allocation for a network with
multiple broadcast channels, where the transmitters access the network
orthogonally on the assigned frequency band and each transmitter communicates
with multiple receivers orthogonally or non-orthogonally. We assume that the
energy harvesting state and channel gain of each transmitter can be predicted
for $K$ slots {\em a priori}. To maximize the weighted throughput, we formulate
an optimization problem with $O(MK)$ constraints, where $M$ is the number of
the receivers, and decompose it into the energy and bandwidth allocation
subproblems. In order to use the iterative algorithm proposed in [1] to solve
the problem, we propose efficient algorithms to solve the two subproblems, so
that the optimal energy-bandwidth allocation can be obtained with an overall
complexity of ${\cal O}(MK^2)$, even though the problem is non-convex when the
broadcast channel is non-orthogonal. For the orthogonal broadcast channel, we
further formulate a proportionally-fair (PF) throughput maximization problem
and derive the equivalence conditions such that the optimal solution can be
obtained by solving a weighted throughput maximization problem. Further, the
algorithm to obtain the proper weights is proposed. Simulation results show
that the proposed algorithm can make efficient use of the harvested energy and
the available bandwidth...

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## A Distributed Cluster Scheme For Bandwidth Management In Multi-hop MANETs

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 08/12/2010

Relevância na Pesquisa

36.19%

Electronic collaboration among devices in a geographically localized
environment is made possible with the implementation of IEEE 802.11 based
wireless ad hoc networks. Dynamic nature of mobile ad hoc networks(MANETs) may
lead to unpredictable intervention of attacks or fault occurrence, which
consequently may partition the network, degrade its performance, violate the
QoS requirements and most importantly, affect bandwidth allocation to mobile
nodes in the network. In this paper, we propose a new distributed cluster
scheme for MANETs, especially in harsh environments, based on the concept of
survivability to support QoS requirements and to protect bandwidth efficiently.
With the incorporation of clustering algorithms in survivability technology, we
employ a simple network configuration and expect to reduce occurrences of
faults in MANETs. At the same time, we address the scalability problem, which
represents a great challenge to network configuration. We do expect a
simplification of accessing bandwidth allocation with required QoS support for
different applications.; Comment: 7 pages, 5 figures

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## Online Bandwidth Allocation

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 25/01/2007

Relevância na Pesquisa

45.97%

#Computer Science - Data Structures and Algorithms#Computer Science - Networking and Internet Architecture

The paper investigates a version of the resource allocation problem arising
in the wireless networking, namely in the OVSF code reallocation process. In
this setting a complete binary tree of a given height $n$ is considered,
together with a sequence of requests which have to be served in an online
manner. The requests are of two types: an insertion request requires to
allocate a complete subtree of a given height, and a deletion request frees a
given allocated subtree. In order to serve an insertion request it might be
necessary to move some already allocated subtrees to other locations in order
to free a large enough subtree. We are interested in the worst case average
number of such reallocations needed to serve a request.
It was proved in previous work that the competitive ratio of the optimal
online algorithm solving this problem is between 1.5 and O(n). We partially
answer the question about its exact value by giving an O(1)-competitive online
algorithm.
Same model has been used in the context of memory management systems, and
analyzed for the number of reallocations needed to serve a request in the worst
case. In this setting, our result is a corresponding amortized analysis.

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## Self-Stabilizing TDMA Algorithms for Dynamic Wireless Ad-hoc Networks

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Relevância na Pesquisa

35.98%

#Computer Science - Networking and Internet Architecture#Computer Science - Distributed, Parallel, and Cluster Computing

In dynamic wireless ad-hoc networks (DynWANs), autonomous computing devices
set up a network for the communication needs of the moment. These networks
require the implementation of a medium access control (MAC) layer. We consider
MAC protocols for DynWANs that need to be autonomous and robust as well as have
high bandwidth utilization, high predictability degree of bandwidth allocation,
and low communication delay in the presence of frequent topological changes to
the communication network. Recent studies have shown that existing
implementations cannot guarantee the necessary satisfaction of these timing
requirements. We propose a self-stabilizing MAC algorithm for DynWANs that
guarantees a short convergence period, and by that, it can facilitate the
satisfaction of severe timing requirements, such as the above. Besides the
contribution in the algorithmic front of research, we expect that our proposal
can enable quicker adoption by practitioners and faster deployment of DynWANs
that are subject changes in the network topology.

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## Fairness for ABR multipoint-to-point connections

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 22/09/1998

Relevância na Pesquisa

36.06%

In multipoint-to-point connections, the traffic at the root (destination) is
the combination of all traffic originating at the leaves. A crucial concern in
the case of multiple senders is how to define fairness within a multicast group
and among groups and point-to-point connections. Fairness definition can be
complicated since the multipoint connection can have the same identifier
(VPI/VCI) on each link, and senders might not be distinguishable in this case.
Many rate allocation algorithms implicitly assume that there is only one sender
in each VC, which does not hold for multipoint-to-point cases. We give various
possibilities for defining fairness for multipoint connections, and show the
tradeoffs involved. In addition, we show that ATM bandwidth allocation
algorithms need to be adapted to give fair allocations for multipoint-to-point
connections.; Comment: Proceedings of SPIE 98, November 1998

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## Optimal Bandwidth and Power Allocation for Sum Ergodic Capacity under Fading Channels in Cognitive Radio Networks

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 25/06/2010

Relevância na Pesquisa

36.29%

This paper studies optimal bandwidth and power allocation in a cognitive
radio network where multiple secondary users (SUs) share the licensed spectrum
of a primary user (PU) under fading channels using the frequency division
multiple access scheme. The sum ergodic capacity of all the SUs is taken as the
performance metric of the network. Besides all combinations of the peak/average
transmit power constraints at the SUs and the peak/average interference power
constraint imposed by the PU, total bandwidth constraint of the licensed
spectrum is also taken into account. Optimal bandwidth allocation is derived in
closed-form for any given power allocation. The structures of optimal power
allocations are also derived under all possible combinations of the
aforementioned power constraints. These structures indicate the possible
numbers of users that transmit at nonzero power but below their corresponding
peak powers, and show that other users do not transmit or transmit at their
corresponding peak power. Based on these structures, efficient algorithms are
developed for finding the optimal power allocations.; Comment: 28 pages, 6 figures, submitted to the IEEE Trans. Signal Processing
in June 2010

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## A note on the data-driven capacity of P2P networks

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 16/09/2009

Relevância na Pesquisa

36.06%

#Computer Science - Data Structures and Algorithms#Computer Science - Networking and Internet Architecture

We consider two capacity problems in P2P networks. In the first one, the
nodes have an infinite amount of data to send and the goal is to optimally
allocate their uplink bandwidths such that the demands of every peer in terms
of receiving data rate are met. We solve this problem through a mapping from a
node-weighted graph featuring two labels per node to a max flow problem on an
edge-weighted bipartite graph. In the second problem under consideration, the
resource allocation is driven by the availability of the data resource that the
peers are interested in sharing. That is a node cannot allocate its uplink
resources unless it has data to transmit first. The problem of uplink bandwidth
allocation is then equivalent to constructing a set of directed trees in the
overlay such that the number of nodes receiving the data is maximized while the
uplink capacities of the peers are not exceeded. We show that the problem is
NP-complete, and provide a linear programming decomposition decoupling it into
a master problem and multiple slave subproblems that can be resolved in
polynomial time. We also design a heuristic algorithm in order to compute a
suboptimal solution in a reasonable time. This algorithm requires only a local
knowledge from nodes...

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## Practical Resource Allocation Algorithms for QoS in OFDMA-based Wireless Systems

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 08/11/2007

Relevância na Pesquisa

36.03%

In this work we propose an efficient resource allocation algorithm for OFDMA
based wireless systems supporting heterogeneous traffic. The proposed algorithm
provides proportionally fairness to data users and short term rate guarantees
to real-time users. Based on the QoS requirements, buffer occupancy and channel
conditions, we propose a scheme for rate requirement determination for delay
constrained sessions. Then we formulate and solve the proportional fair rate
allocation problem subject to those rate requirements and power/bandwidth
constraints. Simulations results show that the proposed algorithm provides
significant improvement with respect to the benchmark algorithm.; Comment: To be presented at 2nd IEEE International Broadband Wireless Access
Workshop. Las Vegas, Nevada USA Jan 12 2008

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