Passive Optical Network Technology Research Articles

100 Gb/s to 1 Tb/s Based Coherent Passive Optical Network Technology

Following on from current 1 Gb/s to 10 Gb/s based passive optical networks (PON), IEEE 802.3ca has commenced discussion of the first 100 Gb/s-based PON standard in the form of 100 G Ethernet PON (100G-EPON), in anticipation of growing bandwidth demand by emerging applications such as fixed-mobile convergence for 5G and beyond 5G (B5G) where mobile front-haul and mobile back-haul (MFH/MBF) will require greatly increased capacity of up to 1 Tb/s. In the move toward these 100 Gb/s to 1 Tb/s class PONs, research into the latest coherent technology based PON systems is being pursued due to its high receiver sensitivity at much higher bit rates, superior to current direct-detection based PON systems, aided by the rapid progress of the latest small-scale digital signal processing (DSP) suitable for access spans of less than a few tens of km. In this paper, we review the recent progress of such 100 Gb/s to 1 Tb/s class coherent PON technology. As the key successful factor for realizing 100 Gb/s to 1 Tb/s based coherent PON systems, the latest trends in coherent DSP and the accompanying embedded coherent transceivers are summarized from the point of view of miniaturization. In addition, highlighting the strong progress with the upcoming coherent PON systems, the first demonstration of a 100 Gb/s/λ × 8 wavelengths (800 Gb/s) based real-time wavelength division multiplexing (WDM)-PON system using a simplified DSP suitable for access spans is presented. A 100 Gb/s/λ based time division multiplexing (TDM)-PON system is also introduced, addressing the burst-mode coherent reception technique which will be the main issue for achieving practical TDM-based coherent PON systems.

Application of Passive Optical Network Technology in Distribution Network Automation

Abstract:For power companies, numerous equipment and devices play important roles in their daily operation. Distribution network serves a quite crucial part, which guarantees its better performance and can better the power transmission. That being the case, automation technology emerges in the distribution network application and hence the distribution network automation (DNA) is formed. Aiming at enhancing yet even more the performance of the distribution network automation, this paper studied the application of passive optical network technology in the distribution network automation technology, hoping to lay a sound foundation for the development of China’s power industry.

How Does Passive Optical Network Tackle Radio Access Network Evolution?

This paper describes full service access network operator group perspectives on the feasibility of optical access networks to carry radio access network traffic for the existing and future mobile generations. The paper discusses topics related to the evolution of radio access interfaces, such as backhaul, midhaul, and fronthaul, their transmission through optical distribution networks, and passive optical network technology feasibility based on both time and wavelength division multiplexing and multiple accesses. Technology extensions are also discussed to provide guidance for future research.

Performance Evaluation of XG-PON Based Mobile Front-Haul Transport in Cloud-RAN Architecture

Time division multiplexing passive optical network (TDM-PON) technologies are viewed as an attractive solution for flexible and cost-efficient mobile front-haul for cloud radio access network (C-RAN) architecture. However, it is a challenge for TDM-PONs to meet the strict latency requirement of mobile front-haul in C-RAN because they use a dynamic bandwidth allocation (DBA) mechanism to manage upstream traffic. The latency issue of TDM-PON based mobile front-haul has been extensively investigated in the literature with particular focus on IEEE TDM-PON (e.g., 10G-EPON). However, ITU TDM-PONs such as XG-PON and XGS-PON have not yet even been explored in the context of mobile front-haul. To cover this gap, we first evaluate the performance of two recently proposed XG-PON-standard-compliant DBAs, namely, group-assured GIANT (gGIANT) and round-robin DBA (RR-DBA), over simulated mobile front-haul traffic. We conclude based on our evaluation that neither RR-DBA nor gGIANT satisfies the delay required for mobile front-haul. Therefore, we propose an optimized DBA known as optimized round-robin (optimized-RR) that support front-hauling over XG-PONs. The performance evaluation of our optimized DBA against gGIANT and RR-DBA shows significant improvement in upstream delay and utilization as well as lower packet loss and jitter for front-haul uplink traffic transmitted via XG-PON in virtualized C-RAN architecture.

Технологии передачи данных в современных системах релейной защиты и автоматики и их показатели качества

This article explores RS-485, Ethernet interfaces performance, quality of communication channels, currently used for the organization of information collection and transmission substations. It is suggested to use GPON-based passive optical network technology as a solution to the existing problem of electromagnetic effects on copper communication channels and high cost of telecommunications equipment (switches, routers, gateways) for fiber-optic channels. It is also calculated (Ping) and analysis (BER) for GPON technology. It was concluded, that it’s feasible to organize information collection and transmission system with the GPON-technology.

Demonstration of Raman-based, dispersion-managed VCSEL technology for fibre-to-the-hut application

Abstract For the first time, we experimentally investigate the use of vertical cavity surface emitting lasers (VCSELs) in the fibre-to-the-home (FTTH) flavour for Africa, known as fibre-to-the-hut. Fibre-to-the-hut is a VCSEL based passive optical network technology designed and optimized for African continent. VCSELs have attracted attention in optical communication due to its vast advantages; low power consumption, relatively cheap costs among others. A 4.25 Gb/s uncooled VCSEL is used in a dispersion managed, Raman assisted network achieving beyond 100 km of error free transmission suited for FTTHut scenario. Energy-efficient high performance VCSEL is modulated using a 27-1 PRBS pattern and the signal transmitted on a G.655 fibre utilizing the minimum attenuation window.

PON Roadmap [Invited

With the recent conclusion of the XGS-PON and NG-PON2 standards in the ITU-T, the fiber access industry is now considering where to go next. This paper reviews the passive optical network (PON) systems market and the services that will drive the take-up of these next-generation PON technologies. The drivers for future PON evolution are discussed, and some technology options for the evolution of PON systems are highlighted.

An improved weighted IPACT algorithm of EPONs in smart distribution networks based on the requirements of relay protection

Summary Because of the capacity of satisfying the quality of service requirements of each traffic service in smart distribution networks, Ethernet passive optical network (EPON) technology is one of the primary technologies for establishing communication systems in smart distribution networks. This paper presents an improved weighted interleaved polling with adaptive cycle time (IW-IPACT) algorithm according to the quality of service requirement of different traffic classes, especially the requirement of the new protection and control technique. During a polling cycle, a virtual weighted buffer queue that meets the bandwidth requirements of the EPON was constructed. Thus, strict priority scheduling was used for the expedited forwarding service, and the weighted fair queuing scheduling was applied for the other services. In addition, to evaluate the real-time performance of the IW-IPACT algorithm, the upper bound for the packet delay of each traffic class was derived by using the network calculus method. The evaluation results indicate that the bandwidth utilization of the EPON was improved by using the IW-IPACT algorithm. In addition, the calculus and OPNET simulation results also show that the EPON can meet the real-time requirements of relay protection. Copyright © 2016 John Wiley & Sons, Ltd.

Building an Energy-efficient Uplink and Downlink Delay Aware TDM-PON System

Abstract With the increasing concern over the energy expenditure due to rapid ICT expansion and growth of Internet traffic volume, there is a growing trend towards developing energy-efficient ICT solutions. Passive Optical Network (PON), which is regarded as a key enabler to facilitate high speed broadband connection to individual subscribers, is considered as one of the energy-efficient access network technologies. However, an immense amount of research effort can be noticed in academia and industries to make PON more energy-efficient. In this paper, we aim at improving energy saving performance of Time Division Multiplexing (TDM)-PON, which is the most widely deployed PON technology throughout the world. A commonly used approach to make TDM-PON energy-efficient is to use sleep mode in Optical Network Units (ONUs), which are the customer premises equipment of a TDM-PON system. However, there is a strong trade-off relationship between traffic delay performance of an ONU and its energy saving (the longer the sleep interval length of an ONU, the lower its energy consumption, but the higher the traffic delay, and vice versa). In this paper, we propose an Energy-efficient Uplink and Downlink Delay Aware (EUDDA) scheme for TDM-PON system. The prime object of EUDDA is to meet both downlink and uplink traffic delay requirement while maximizing energy saving performance of ONUs as much as possible. In EUDDA, traffic delay requirement is given more priority over energy saving. Even so, it still can improve energy saving of ONUs noticeably. We evaluate performance of EUDDA in front of two existing solutions in terms of traffic delay, jitter, and ONU energy consumption. The performance results show that EUDDA significantly outperforms the other existing solutions.

Provisioning 1 Gb/s symmetrical services with next-generation passive optical network technologies

Service providers spend billions upgrading their broadband access networks to the latest access standards. Fiber has become the technology of choice in the medium and long term, thanks to its speed, reach, and future-proofness. A differential advantage of fiber over other broadband access technologies is that it makes it possible for operators to deliver symmetric-rate services. Most of today’s commercial offers based on regular PON range from 10 to 100 Mb/s of committed information rate, and higher rates are advertised as peak rates with unspecified guarantees. In this article we focus on delivering symmetrical 1 Gb/s access to residential users with a target temporal guarantee at the least cost using next-generation PON technologies. We compare four NG-PON standard access technologies, GPON, XGPON, WDM-PON, and the emerging TWDM-PON, from technical and economic perspectives. The study shows that if a service provider wants to keep up with the growing user traffic pattern in the long run, only TWDM-PON can provide 1 Gb/s nearly guaranteed at a moderate cost with respect to the fully dedicated 1 Gb/s point-to-point connection available in WDM-PON technologies.

Ultra-broadband access enabled by fiber optics (Invited Paper)

The advent of low loss optical fiber has consistently led us to the ultra-broadband era, where bandwidths exceeding 1 Gb/s are commonplace. This Review reviews the early history of fiber access, pointing out some of the lasting design choices and signature features of fiber access. The progress of the various passive optical network technologies is also reviewed, and some views regarding the future trends of fiber in the access.

Design and Evaluation of Elastic Optical Access Network Based on WDM-PON and OFDM Technology

The elastic optical network is a novel idea that is targeted at realizing flexible bandwidth allocation according to diverse traffic needs and requirements. Meanwhile, with the increasing demand of data rates in optical access networks, it is urgent to upgrade the current passive optical networks (PONs) through more elastic approaches. In this paper, we propose a kind of elastic optical access network based on wavelength-division multiplexing PON (WDM-PON) and orthogonal frequency-division multiplexing (OFDM) technology, in which finer bandwidth allocation granularity and a flexible wavelength switch are realized. We simulate the transmission performance of the system in both uplinks and downlinks.We also evaluate the elasticity of the system and propose an improved dynamic bandwidth allocation algorithm that has been shown to be the most effective in reducing the blocking rate and bandwidth fragmentation.

Reach extendibility of passive optical network technologies

Fiber to The Home (FTTH) Passive Optical Networks (PONs) are becoming popular because of their ability to accommodate the varying demands of the users regarding, voice, data and multimedia services. This paper compares, analyzes and proposes a method to extend the reach of various PON technologies like Ethernet Passive Optical Network (EPON), Gigabit Passive Optical Network (GPON) and XGPON. These technologies are analyzed and evaluated for the performance on the basis of parameters like Bit Error Rate (BER), Quality factor (Q factor), Signal to Noise Ratio (SNR) and input output powers at multiple distances. For the analysis of PON technologies, different split ratios like 1:8, 1:16, 1:32 and 1:64 are also considered. The results of this research reveal that the EPON performs better only up to a distance of 60km with the maximum of 16 users. It has been observed that the GPON exhibits more reach extendibility than the EPON by using Erbium Doped Fiber Amplifier (EDFA) for the extended number of users, i.e. 32 users. It has also been observed that the XGPON supports reach extendibility up to 80km by using EDFA. XGPON provides higher bandwidth efficiency per subscriber and with overall improved performance it can accommodates greater number of users i.e. 64 users.

QoS-aware energy-efficient mechanism for sleeping mode ONUs in enhanced EPON

Ethernet passive optical network (EPON) is a broadband access time-division multiplexing passive optical network technology which can be referred to as green network, as it has less power consumption compared with other networks. The optical network unit (ONU) is the best candidate to implement energy-saving adjustments in EPON. Turning off the ONU transmitter (Tx)/receiver (Rx) for substantial time is a common method to achieve the energy saving. However, setting overlong sleep duration decreases the QoS, while short sleep duration increases the ONU power consumption. The challenging issue is how to balance the trade-off between achieving energy saving and guaranteeing QoS. In this paper, we introduce an enhanced EPON architecture and a QoS-aware energy-saving mechanism to reduce ONU energy consumption and guarantee an overall QoS metric based on the ITU-T standards requirements. To achieve the energy saving in the upstream/downstream direction, two sleep durations are defined for the ONU's Tx/Rx to generate four ONU modes including active, transmission, doze, and sleep. Simulation results show that the proposed scheme improves the energy efficiency 44 % in average to fulfill the QoS metrics in terms of packet loss, delay and jitter, and the buffer requirement.

A TTC upgrade proposal using bidirectional 10G-PON FTTH technology

A new generation FPGA-based Timing-Trigger and Control (TTC) system based on emerging Passive Optical Network (PON) technology is being proposed to replace the existing off-detector TTC system used by the LHC experiments. High split ratio, dynamic software partitioning, low and deterministic latency, as well as low jitter are required. Exploiting the latest available technologies allows delivering higher capacity together with bidirectionality, a feature absent from the legacy TTC system. This article focuses on the features and capabilities of the latest TTC-PON prototype based on 10G-PON FTTH components along with some metrics characterizing its performance.

Passive Optical Network Survivability: Protection, Detection and Restoration

Passive optical network (PON) technologies have received increasing attention as demand for fibre access networks has grown. Enhancing fibre access network reliability provides lower operational costs, and improves customer satisfaction. This paper discusses PON survivability including protection schemes for the fiber link and the Optical Line Terminal (OLT), the exciting monitoring techniques of the fiber link, and the effect of reducing the restoration time on the network availability. The main contribution of this study is to provide two protection schemes namely OLT-only-protected and OLT-and-ring protected. The proposed schemes are designed to handle instances of single failure affecting all customers in the network. This work considers three key performance metrics- Failure Impact Robustness (FIR), cost, and availability. The objective of the proposed protection architectures is to guarantee high quality of service at low costs by protecting critical network elements such as OLT and fiber ring. The proposed architectures have been compared with other well-known protection schemes. The results postulate that OLT-and-ring protected approach has 99.993% availability with a 0.09% increase in cost compared to the ring-only protection architecture.

NG-PON2 Technology and Standards

This paper provides a tutorial overview of the latest generation of passive optical network (PON) technology standards nearing completion in ITU-T. The system is termed NG-PON2 and offers a fiber capacity of 40 Gbit/s by exploiting multiple wavelengths at dense wavelength division multiplexing channel spacing and tunable transceiver technology in the subscriber terminals (ONUs). Here, the focus is on the requirements from network operators that are driving the standards developments and the technology selection prior to standardization. A prestandard view of the main physical layer optical specifications is also given, ahead of final ITU-T approval.

Energy efficiency analysis of high speed triple-play services in next-generation PON deployments

In this paper, the energy consumption of high speed access services up to 1Gb/s per customer is estimated for different passive optical network (PON) technologies. While other studies on PON power consumption typically assume a fixed split ratio, we also consider a greenfield approach, where the split ratio can be optimized for each technology, taking full advantage of its capacity and reach. The split ratio optimization takes into account Quality of Service (QoS) in terms of bandwidth availability and packet loss for triple-play services (voice, television and Internet). This paper includes an in-depth discussion of our split ratio dimensioning approach and our power consumption model for an optical access network in a major city. The obtained results show that statistical gain provided by dynamic bandwidth allocation as well as power splitting ratio optimization in PONs are key factors for achieving energy efficiency. For access rates up to 900Mb/s, XG-PON1 turns out to be the most energy efficient option. For higher access rates up to 1Gb/s, the optimal technology depends on split ratio restrictions. If an existing optical distribution network (ODN) with split ratio 1:64 is used, XG-PON1 remains the most energy efficient technology. If higher split ratios up to 1:256 can be achieved, TWDM PON becomes the most energy efficient solution for access rates up to 1Gb/s.

Reliability of Multiple-Stage Cascaded Passive Optical Networks: A Perspective

Passive Optical Network (PON) technology has been widely accepted as main broadband access which can satisfy the rapid increasing bandwidth requirements. With the expansion of the number of users, as well as the variation of application scenarios, traditional single-stage cascaded or two-stage cascaded PON system can no longer meet users’ demands. This paper proposed four multiple-stage cascaded PON topologies with different protection schemes. Reliability and cost for each topology are presented with theoretical analysis and numerical simulations.

Service Class Resource Management for Green Wireless-Optical Broadband Access Networks (WOBAN)

Exponential growth in the volume of wireless data, boosted by the growing popularity of mobile devices, such as smartphone and tablets, has forced the telecommunication industries to rethink the way networks are currently designed, and to focus on the development of high-capacity mobile broadband networks. In response to this challenge, researchers have been working toward the development of an integrated wireless optical broadband access network. Two major candidate technologies, which are currently known for their high capacity as well as quality of service (QoS) for multimedia traffic, are passive optical networks (PON), and fourth generation (4G) wireless networks. PON is a wired access technology, well known for its cost efficiency and high capacity; whereas 4G is a wireless broadband access technology, which has achieved broad market acceptance because of its ease of deployment, ability to offer mobility, and its cost efficiency. Integration of PON and 4G technologies in the form of wireless-optical broadband access networks, offers advantages, such as extension of networks in rural areas, support for mobile broadband services, and quick deployment of broadband networks. These two technologies however, have different design architectures for handling broadband services that require quality of service. For example, 4G networks use traffic classification for supporting different QoS demands, whereas the PON architecture has no such mechanism to differentiate between types of traffic. These two technologies also differ in their power saving mechanisms. In this paper, we propose a service class mapping for the integrated PON-4G network, which is based on the M/G/1 queuing model. We also propose a class-based power saving mechanism which significantly improves the sleep period for the integrated optical wireless unit, without compromising support for QoS. Results indicate that our proposed class-based power saving scheme reduces power consumption by up to 80%, and maintains the QoS within the requirements of the service level agreement.