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Ethernet Passive Optical Networks (EPONs) are designed to deliver multiple services and applications, such as voice communications, standard (SDTV) and high-definition video (HDTV). To support these applications and their various requirements, EPONs require Quality-of-Service (QoS) mechanisms to be built in service. For this purpose, a scalable Interleaved Dynamic Bandwidth Allocation (IDBA) mechanism for sharing the uplink bandwidth among optical network units (ONUs) is proposed in this paper. The modus operandi of IDBA is to divide the cycle time by partitioning the ONUs into two groups with some timing overlap to execute interleaved bandwidth allocation, which cooperates with Limited Bandwidth Allocation (LBA), Excess Bandwidth Reallocation (EBR) and accurate prediction mechanism in EPONs. The proposed IDBA mechanism has two advantages, namely it eliminates the idle period problem in the traditional DBA mechanism, and guarantees QoS services by dynamically adjusting the bandwidth within the group of subscribers. This will not only support the differentiated services architecture but also offer various QoS levels. Simulation results obtained show that the proposed IDBA mechanism achieves desirable system performance relative to packet delay, jitter performance, throughput, ratio of packet loss and fairness. [ABSTRACT FROM AUTHOR]

In the EPON, many previous studies proposed dedicated protection architectures to protect the critical components which results in high cost for deployment. To achieve high reliability and low-cost for deployment, this article proposes a novel fault-tolerant Multi-EPON system with cost-effective shared protection through Bridge ONUs. Under the failures, the Bridge ONU controls the faulty EPON, plays the role of OLT and the transmission of faulty EPONs is restored by relaying to other interconnected adjacent EPONs. The minimum hop count relay algorithm and the relay window mechanism are also proposed in this article to help the data for relaying efficiently. Furthermore, the One-Wait DBA enables the controller of affected PONs to obtain more up-to-date buffer information from each ONU in order to enhance overall system performance. The simulation results show that the proposed Multi-EPON system can provide high system performance for different failed situations in terms of average delay, MAX delay and EF jitter, especially in high traffic loads. [ABSTRACT FROM AUTHOR]

As the era of converging digital industry takes shape, to make full use of huge bandwidth offered by fiber and mobile characteristics, the integration of wireless and optical networks is a potential solution for increasing capacity and mobility as well as decreasing costs in the access network. In this paper we present the basic architecture of an emerging integration of EPON and hybrid wireless networks, and propose an efficient scheduling to deliver diverse services by taking the quality of service (QoS) requirement into consideration. The simulation results demonstrate that our scheme is capable of collecting the QoS requirement information throughout the network, and the process facilitates the reduction of network transmission overhead. [ABSTRACT FROM AUTHOR]