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Multimedia applications over the Internet, such as IPTV and video-on-demand, have become fast growing applications in recent years. Such applications have stringent quality of services (QoS) constraints in terms of bandwidth, delay, and packet loss. As a consequence, broadband access networks play an important role for multimedia applications. There are two emerging technologies offering both high bandwidth and QoS support, namely Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX). By integrating these two technologies, EPON-WiMAX integrated network can: (1) provide broadband access, (2) support mobile users, and (3) decrease network planning cost and operating cost. Thus, EPON-WiMAX integrated network is an ideal choice for multimedia applications with ubiquitous access. Although EPON-WiMAX integrated network has received growing attentions, however, most of previous works focus on the scheduling and bandwidth allocation in the upstream direction. Therefore, in this paper, we investigate the downlink scheduling and bandwidth allocation problem in EPON-WiMAX integrated networks. The objective of the study is to maximize the system throughput and guarantee the (QoS) so that the requirements of multimedia applications can be fulfilled. We proposed a two-stage downlink packet scheduling and resource allocation mechanism collaborating with application layer forward error correction (AL-FEC). We demonstrated the performance of our approach via simulations. Our simulation results indicated that the proposed mechanism increased the system throughput significantly, especially when AL-FEC is adopted.

Multimedia applications over Internet, such as IPTV and video on demand (VoD), have become fast growing applications in recent years. Such applications have stringent QoS constraints in terms of bandwidth, delay and packet loss. As a consequence, broadband access networks play an important role for multimedia applications. There are two emerging technologies offering both high bandwidth and QoS support, that is, Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX). By integrating these two technologies, EPONWiMAX integrated network can: (1) provide broadband access, (2) support mobile users, and (3) decrease network planning cost and operating cost. Thus, EPON-WiMAX integrated network is an ideal choice for multimedia applications with ubiquitous access. Although EPON-WiMAX integrated network has received growing attentions, however, most of previous works focus on the uplink scheduling and bandwidth allocation. Therefore, in this paper, we investigate the downlink scheduling and bandwidth allocation problem in EPON-WiMAX integrated networks. The objective of the study is to maximize the system throughput and guarantee the quality of service so that the requirements of multimedia applications can be fulfilled. We proposed a two-stage downlink scheduling and resource allocation mechanism collaborating with application layer forward error correction (AL-FEC). We demonstrate the performance of our approach via simulations. Our simulation results indicate that the proposed mechanism can increase the system throughput significantly, especially when AL-FEC is adopted.

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The rapid growth of the demand of multimedia applications in recent years has posted a much higher bandwidth demand than before. As a result, the technology of broadband access is becoming more and more important. Integrating Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX) has been considered as a very promising solution for broadband access. Although EPON-WiMAX has received many attentions in research, yet most of the previous researches focus on the uplink packet scheduling and bandwidth allocation. Thus, in our research, we focus on the downlink scheduling and resource allocation problem. In particular, we focus on utilizing the cooperative transmission technique. Based on the advantage of EPON-WiMAX architecture, the resource allocation problem utilizing cooperative transmission can be done at the optical line terminal (OLT) in a centralized manner. We first formulate the problem as a linear programming (LP) problem. Due to the high complexity of LP, we propose a heuristic algorithm to solve the problem. Our simulation results show that the proposed algorithm is able to increase the system throughput while guaranteeing the QoS of different classes of traffic.