Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both f...Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both full-duplex EPON system and half-duplex EPON system using CSMA/CD were proposed. In the full-duplex EPON, CSMA/CD is used as the upstream MAC protocol. In the half-duplex EPON system, both upstream and downstream traffic contend for the optical channel through CSMA/CD protocol. The upstream lightwave redirection and collision detection techniques were given. By the analysis and simulation, the throughput performance of the half-duplex EPON system is proven to be as well as that of the existing high speed half-duplex Ethernet LAN.展开更多
This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programm...This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programmable gate array （FPGA） with an embedded CPU. To reduce working frequency of the FPGA, the byte-to-word conversion is proposed. Propagation delays are equalized by ranging procedure so as to avoid data collision. Implementations of synchronization, classification, as well as Linux porting are illustrated in detail. The interface between the FPGA and CPU are also presented. Experimental results show that the proposed system can properly function in a relatively low cost FPGA.展开更多
The Ethernet passive optical network(EPON) is the next generation of broad-band network technique.A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units(ONUs).This article provides a n...The Ethernet passive optical network(EPON) is the next generation of broad-band network technique.A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units(ONUs).This article provides a novel dynamic bandwidth allocation algorithm,i.e.threshold dynamic bandwidth allocation(TDBA),which is based on adaptive threshold,to increase resource utilization.The algorithm uses ONU data-transmitting rate to adjust optical line terminal(OLT) receiving data threshold from an ONU.Simulation results show that this algorithm can decrease average packet delay and increase network throughput in a 10G EPON system.展开更多
Dynamic bandwidth allocation（DBA） is an open and hot topic in the Ethernet passive optical network（EPON） ,which is regarded as one of the best choices for next-generation access networks. However,most proposed DBA...Dynamic bandwidth allocation（DBA） is an open and hot topic in the Ethernet passive optical network（EPON） ,which is regarded as one of the best choices for next-generation access networks. However,most proposed DBA schemes ignore the quality of service（QoS） guarantee on maximum delay and delay jitter for the real-time traffic and the downstream bandwidth utilization under light upstream load in EPON. In this paper,a new DBA scheme,QoS guaranteed adaptive downstream bandwidth utilization（QoS-ADBU）,is proposed. This scheme can provide better QoS assurance by determining the maximum transmission cycle time according to the maximum acceptable packet delay and delay jitter for real-time traffic. Besides,the downstream utilization can also be improved by adapting the polling frequency to downstream traffic load.展开更多
With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought b...With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought by diversified-services,this study proposes an echo state network( ESN)based multi-service awareness mechanism in 10-Gigabite ethernet passive optical network( 10GEPON). In the proposed approach,distributed architecture is adopted to realize this ESN based multi-service awareness. According to the network architecture of 10G-EPON,where a main ESN is running in OLT and a number of ESN agents works in ONUs. The main-ESN plays the main function of service-awareness from the total view of various kinds of services in 10G-EPON system,by full ESN training. Then,the reservoir information of well-trained ESN in OLT will be broadcasted to all ONUs and those ESN agents working in ONUs are allowed to conduct independent service-awareness function. Thus,resources allocation and transport policy are both determined only in ONUs. Simulation results show that the proposed mechanism is able to better support the ability of multiple services.展开更多
To increase the limit of ethernet over coax(EoC)technology in the bidirectional reform of the hybrid fiber coaxial(HFC)network,an ethernet passive electronic network(EPEN)system based on Coax is proposed and experimen...To increase the limit of ethernet over coax(EoC)technology in the bidirectional reform of the hybrid fiber coaxial(HFC)network,an ethernet passive electronic network(EPEN)system based on Coax is proposed and experimentally demonstrated in this paper.The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network(EPON)for reduction of cost of the HFC network.As the MPCP(multi-point control protocol)is introduced in the EPEN,bandwidth control and higher efficiency can be achieved.The experimental results exhibit the throughput of system up to 100Mbps,which meet the requirements of HFC network.To improve the performance of EPEN,frequency division multiplexing(FDM)can be used for further increase of the throughput and more hardware processing modules can be implemented to enhance the capacity in the future.展开更多
As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic ...As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of -the-art solutions to emulating optical local area networks （OLANs） over EPON. We discuss the major problems involved, e.g., network architecture, control mechanisms, and other potential enhancements. We also outline areas for future researches.展开更多
Hybrid wavelength-division-multiplexing(WDM)/time-division-multiplexing(TDM) ethernet passive optical networks(EPONs) can achieve low per-subscriber cost and scalability to increase the number of subscribers. This pap...Hybrid wavelength-division-multiplexing(WDM)/time-division-multiplexing(TDM) ethernet passive optical networks(EPONs) can achieve low per-subscriber cost and scalability to increase the number of subscribers. This paper discusses dynamic wavelength and bandwidth allocation(DWBA) algorithm in hybrid WDM/TDM EPONs.Based on the correlation structure of the variable bit rate(VBR) video traffic,we propose a quality-ofservice (QoS) supported DWBA using adaptive linear traffic prediction.Wavelength and timeslot are allocated dynamically by optical line terminal(OLT) to all optical network units(ONUs) based on the bandwidth requests and the guaranteed service level agreements(SLA) of all ONUs.Mean square error of the predicted average arriving rate of compound video traffic during waiting period is minimized through Wiener-Hopf equation.Simulation results show that the DWBA-adaptive-linear-prediction(DWBA-ALP) algorithm can significantly improve the QoS performances in terms of low delay and high bandwidth utilization.展开更多
We demonstrate that an asynchronous CSMA/CD protocol with an optical loop-back star coupler can achieve high upstream channel utilizatbn in an Ethernet PON, readily supporting a large installed base of Ethernet 10Base...We demonstrate that an asynchronous CSMA/CD protocol with an optical loop-back star coupler can achieve high upstream channel utilizatbn in an Ethernet PON, readily supporting a large installed base of Ethernet 10BaseT and 100BaseT interfaces.展开更多
文摘Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both full-duplex EPON system and half-duplex EPON system using CSMA/CD were proposed. In the full-duplex EPON, CSMA/CD is used as the upstream MAC protocol. In the half-duplex EPON system, both upstream and downstream traffic contend for the optical channel through CSMA/CD protocol. The upstream lightwave redirection and collision detection techniques were given. By the analysis and simulation, the throughput performance of the half-duplex EPON system is proven to be as well as that of the existing high speed half-duplex Ethernet LAN.
基金Project supported by Science Foundation of Shanghai Municipal Commission of Science and Technology (Grant No .04dz12045)
文摘This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programmable gate array （FPGA） with an embedded CPU. To reduce working frequency of the FPGA, the byte-to-word conversion is proposed. Propagation delays are equalized by ranging procedure so as to avoid data collision. Implementations of synchronization, classification, as well as Linux porting are illustrated in detail. The interface between the FPGA and CPU are also presented. Experimental results show that the proposed system can properly function in a relatively low cost FPGA.
文摘The Ethernet passive optical network(EPON) is the next generation of broad-band network technique.A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units(ONUs).This article provides a novel dynamic bandwidth allocation algorithm,i.e.threshold dynamic bandwidth allocation(TDBA),which is based on adaptive threshold,to increase resource utilization.The algorithm uses ONU data-transmitting rate to adjust optical line terminal(OLT) receiving data threshold from an ONU.Simulation results show that this algorithm can decrease average packet delay and increase network throughput in a 10G EPON system.
基金supported by the Tianjin Enterprise Innovation Fund under Grant No. 08ZXCXGX17500
文摘Dynamic bandwidth allocation（DBA） is an open and hot topic in the Ethernet passive optical network（EPON） ,which is regarded as one of the best choices for next-generation access networks. However,most proposed DBA schemes ignore the quality of service（QoS） guarantee on maximum delay and delay jitter for the real-time traffic and the downstream bandwidth utilization under light upstream load in EPON. In this paper,a new DBA scheme,QoS guaranteed adaptive downstream bandwidth utilization（QoS-ADBU）,is proposed. This scheme can provide better QoS assurance by determining the maximum transmission cycle time according to the maximum acceptable packet delay and delay jitter for real-time traffic. Besides,the downstream utilization can also be improved by adapting the polling frequency to downstream traffic load.
基金Supported by the National High Technology Research and Development Programme of China(No.2012AA050804)
文摘With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought by diversified-services,this study proposes an echo state network( ESN)based multi-service awareness mechanism in 10-Gigabite ethernet passive optical network( 10GEPON). In the proposed approach,distributed architecture is adopted to realize this ESN based multi-service awareness. According to the network architecture of 10G-EPON,where a main ESN is running in OLT and a number of ESN agents works in ONUs. The main-ESN plays the main function of service-awareness from the total view of various kinds of services in 10G-EPON system,by full ESN training. Then,the reservoir information of well-trained ESN in OLT will be broadcasted to all ONUs and those ESN agents working in ONUs are allowed to conduct independent service-awareness function. Thus,resources allocation and transport policy are both determined only in ONUs. Simulation results show that the proposed mechanism is able to better support the ability of multiple services.
基金Supported by the National High Technology Research and Development Program of China(No.2007AA01Z229)
文摘To increase the limit of ethernet over coax(EoC)technology in the bidirectional reform of the hybrid fiber coaxial(HFC)network,an ethernet passive electronic network(EPEN)system based on Coax is proposed and experimentally demonstrated in this paper.The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network(EPON)for reduction of cost of the HFC network.As the MPCP(multi-point control protocol)is introduced in the EPEN,bandwidth control and higher efficiency can be achieved.The experimental results exhibit the throughput of system up to 100Mbps,which meet the requirements of HFC network.To improve the performance of EPEN,frequency division multiplexing(FDM)can be used for further increase of the throughput and more hardware processing modules can be implemented to enhance the capacity in the future.
基金the National Science Fund for Distinguished Young Scholars(Grant No.60725104)the National Basic Research Program of China(Grant No.2007CB310706)+2 种基金the National High Technology Research and Development Program of China(Grant Nos.2007AA01Z246 and 2007AA01Z227)the National Natural Science Foundation of China(Grant No.60672045)the Research Fund for the Doctoral Program of Higher Education(Grant No.20060614018)
文摘As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of -the-art solutions to emulating optical local area networks （OLANs） over EPON. We discuss the major problems involved, e.g., network architecture, control mechanisms, and other potential enhancements. We also outline areas for future researches.
文摘Hybrid wavelength-division-multiplexing(WDM)/time-division-multiplexing(TDM) ethernet passive optical networks(EPONs) can achieve low per-subscriber cost and scalability to increase the number of subscribers. This paper discusses dynamic wavelength and bandwidth allocation(DWBA) algorithm in hybrid WDM/TDM EPONs.Based on the correlation structure of the variable bit rate(VBR) video traffic,we propose a quality-ofservice (QoS) supported DWBA using adaptive linear traffic prediction.Wavelength and timeslot are allocated dynamically by optical line terminal(OLT) to all optical network units(ONUs) based on the bandwidth requests and the guaranteed service level agreements(SLA) of all ONUs.Mean square error of the predicted average arriving rate of compound video traffic during waiting period is minimized through Wiener-Hopf equation.Simulation results show that the DWBA-adaptive-linear-prediction(DWBA-ALP) algorithm can significantly improve the QoS performances in terms of low delay and high bandwidth utilization.
文摘We demonstrate that an asynchronous CSMA/CD protocol with an optical loop-back star coupler can achieve high upstream channel utilizatbn in an Ethernet PON, readily supporting a large installed base of Ethernet 10BaseT and 100BaseT interfaces.
