Algoritmo de Policiamento de Tráfego para Redes OFDM/TDMA WiMAX Baseado em Modelagem Multifractal e Cálculo de Rede

• Autor(a) principal: SANTOS JUNIOR, Josemar Alves dos
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/968
• topic: Modelagem Multifractal; Algoritmo de Policiamento; Cálculo de Rede; Tráfego de Rede; WiMAX; Qualidade de Serviço; Retardo; Backlog; Multifractal Modeling; Policing Algorithm; Network Calculus; Network Traffic; WiMAX; Quality of Service; Delay; Backlog.; CNPQ::ENGENHARIAS::ENGENHARIA ELETRICA

The multifractal modeling is more appropriate in describing some features finding in traffic flows in real networks than other models. This work investigates the behavior of the traffic modeling based policing algorithms found in the literature (Leaky Bucket, Fractal Leaky Bucket, Gaussian Multifractal Leaky Bucket) regarding the buffer utilization, the efficiency for the use of buffer efficiency in describing the accumulated traffic (envelope process), packet dropping and data loss (bytes). First, we compare the envelope process of the considered policing algorithms and the proposed algorithm MAPM (Multifractal Arrival Policing Mechanism), with traffic without policing. Next, it was calculated the system loss rate for a finity buffer system with and without policing algoritm. Using the deterministic Network Calculus, it is also estimated the average queue length (backlog) and delay of bytes by applying the concept of the Min-Plus algebra that presents some differences against the conventional algebra. The proposed policing algorithm was applied to a transmission system based on OFDM (Orthogonal Frequency - Division Multiplexing) / TDMA (Time Division Multiplexing Access) system, where it was evaluated the network performance of the considered policing algorithms. Simulations were carried out with real wireless network trace (Wi-Fi) and wired network trace in order to demonstrate the efficiency of the algorithm proposed in relation to policing algorithms in the literature. The simulations shown the efficiency of the MAPM policing algorithm with traces from wired and wireless networks. We also propose the use of deterministic Network Calculus associated to multifractal envelope process to analyze the traffic behavior in terms of delay and backlog before policing algorithms application in the network. Finally we present the results of buffer utilization, link utilization, delay and backlog to a WiMAX system where the policing algorithm MAPM in general shown delay and backlog increasing in the traffic compared with anothers algorithms and low link utilization