Energy efficiency analysis of next-generation passive optical network (NG-PON) technologies in a major city network

Ever-increasing bandwidth demands associated with mobile backhaul, content-rich services and the convergence of residential and business access will drive the need for next-generation passive optical networks (NG-PONs) in the long term. At the same time, there is a growing interest in reducing the energy consumption and the associated cost of the access network. In this paper, we consider a deployment scenario in a major city to assess the energy efficiency of various PON solutions from a telecom operator's perspective. We compare five next-generation technologies to a baseline GPON deployment offering similar bandwidths and Quality of Service (QoS) for best-effort high speed connectivity services. We follow two approaches:first, we consider a fixed split ratio (1:64) in an existing Optical Distribution Network (ODN); next, we consider an upgraded ODN with an optimized split ratio for the specific bandwidth and QoS values. For medium bandwidth demands, our results show that legacy PONs can be upgraded to 10G PON without any ODN modification. For future applications that may require access rates up to 1 Gb/s, NG-PON2 technologies with higher split ratios and increased reach become more interesting systems, offering the potential for both increased energy efficiency and node consolidation

A QoS-Aware Dynamic Bandwidth Allocation algorithm for passive optical networks with non-zero laser tuning time

The deployment of new 5G services and future demands for 6G make it necessary to increase the performance of access networks. This challenge has prompted the development of new standardization proposals for Passive Optical access Networks (PONs) that offer greater bandwidth, greater reach and a higher rate of aggregation of users per fiber, being Time- and Wavelength-Division Multiplexing (TWDM) a promising technological solution for increasing the capacity by up to 40 Gbps by using several wavelengths. This solution introduces tunable transceivers into the Optical Network Units (ONUs) for switching from one wavelength to the other, thus addressing the ever-increasing bandwidth demands in residential broadband and mobile fronthaul networks based on Fiber to the Home (FTTH) technology. This adds complexity and sources of inefficiency, such as the laser tuning time (LTT) delay, which is often ignored when evaluating the performance of Dynamic Bandwidth Allocation (DBA) mechanisms. We present a novel DBA algorithm that dynamically handles the allocation of bandwidth and switches the ONUs’ lasers from one wavelength to the other while taking LTT into consideration. To optimize the packet delay, we introduce a scheduling mechanism that follows the Longest Processing Time first (LPT) scheduling discipline, which is implemented over the Interleaved Polling with Adaptive Cycle Time (IPACT) DBA. We also provide quality of service (QoS) differentiation by introducing the Max-Min Weighted Fair Share Queuing principle (WFQ) into the algorithm. The performance of our algorithm is evaluated through simulations against the original IPACT algorithm, which we have extended to support multi-wavelengths. With the introduction of LPT, we obtain an improved performance of up to 73% reduction in queue delay over IPACT while achieving QoS differentiation with WFQ.This work has been supported by the Agencia Estatal de Investigación of Spain under project PID2019‐108713RB‐C51/AEI/10.13039/501100011033.Peer ReviewedObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.1 - Desenvolupar infraestructures fiables, sostenibles, resilients i de qualitat, incloent infraestructures regionals i transfrontereres, per tal de donar suport al desenvolupament econòmic i al benestar humà, amb especial atenció a l’accés assequible i equitatiu per a totes les personesObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.4 - Per a 2030, modernitzar les infraestructures i reconvertir les indústries perquè siguin sostenibles, usant els recursos amb més eficàcia i promovent l’adopció de tecnologies i processos industrials nets i racionals ambiental­ment, i aconseguint que tots els països adoptin mesures d’acord amb les capacitats respectivesPostprint (published version

Fair bandwidth allocation algorithm for PONS based on network utility maximization

Network utility maximization (NUM) models have been successfully applied to address multiple resource- allocation problems in communication networks. This paper explores, for the first time to our knowledge, their application to modeling the bandwidth-allocation problem in passive optical networks (PONs) and long-reach PONs. Using the NUM model, we propose the FEx-DBA (fair excess-dynamic bandwidth allocation) algorithm, a new DBA scheme to allow a fair and efficient allocation of the upstream channel capacity. The NUM framework provides the mathematical support to formally define the fairness concept in the resource allocation and the guidelines to devise FEx-DBA. A simulation study is conducted, whereby FEx-DBA is compared to a state-of-the-art proposal. We show that FEx-DBA (i) provides bandwidth guarantees to the users according to the service level agreement (SLA) contracted and fairly distributes the excess bandwidths among them; (ii) has a stable response and fast convergence when traffic or SLAs change, avoiding the oscillations appearing in other proposals; (iii) improves average delay and jitter measures; and (iv) only depends on a reduced set of parameters, which can be easily tuned.This work has been funded by Spanish Ministry of Science and Innovation (TEC2014-53071-C3-2-P and TEC2015-71932-REDT)

Energy efficiency analysis of next-generation passive optical network (NG-PON) technologies in a major city network

Ever-increasing bandwidth demands associated with mobile backhaul, content-rich services and the convergence of residential and business access will drive the need for next-generation passive optical networks (NG-PONs) in the long term. At the same time, there is a growing interest in reducing the energy consumption and the associated cost of the access network. In this paper, we consider a deployment scenario in a major city to assess the energy efficiency of various PON solutions from a telecom operator's perspective. We compare five next-generation technologies to a baseline GPON deployment offering similar bandwidths and Quality of Service (QoS) for best-effort high speed connectivity services. We follow two approaches:first, we consider a fixed split ratio (1:64) in an existing Optical Distribution Network (ODN); next, we consider an upgraded ODN with an optimized split ratio for the specific bandwidth and QoS values. For medium bandwidth demands, our results show that legacy PONs can be upgraded to 10G PON without any ODN modification. For future applications that may require access rates up to 1 Gb/s, NG-PON2 technologies with higher split ratios and increased reach become more interesting systems, offering the potential for both increased energy efficiency and node consolidation

Simulations of Grant Allocation in NG-PON2 Networks Using OPNET Modeler

Passive optical networks are the most promising networks for the future. In 1998, the first standard of PONs was developed. Since that time, quality of optical transmissions and technologies has been massively improved and today's standards are capable of transferring an enormous amount of data. For example, NG-PON2 networks are able to transfer up to 40 Gbit/s, which means these networks provide subscribers with a symmetric bandwidth up to 10 Gbit/s using 4 different wavelengths. The higher transmission speeds are required, the more sophisticated bandwidth allocation reflecting requirements of each ONU in real-time is necessary. This article deals with implementation of NG-PON2 networks using OPNET Modeler and simulations of static and dynamic grants allocations. We also present a modification of dynamic bandwidth allocation for increasing the free bandwidth of idle ONU to heavily loaded ONU(s). We propose a simplified NG-PON2 network, for example, activation machine for ONUs is not implemented

Simulations of Grant Allocation in NG-PON2 Networks Using OPNET Modeler

Passive optical networks are the most promising networks for the future. In 1998, the first standard of PONs was developed. Since that time, quality of optical transmissions and technologies has been massively improved and today\u27s standards are capable of transferring an enormous amount of data. For example, NG-PON2 networks are able to transfer up to 40 Gbit/s, which means these networks provide subscribers with a symmetric bandwidth up to 10 Gbit/s using 4 different wavelengths. The higher transmission speeds are required, the more sophisticated bandwidth allocation reflecting requirements of each ONU in real-time is necessary. This article deals with implementation of NG-PON2 networks using OPNET Modeler and simulations of static and dynamic grants allocations. We also present a modification of dynamic bandwidth allocation for increasing the free bandwidth of idle ONU to heavily loaded ONU(s). We propose a simplified NG-PON2 network, for example, activation machine for ONUs is not implemented

Supporting Diverse Customers and Prioritized Traffic in Next-Generation Passive Optical Networks

The already high demand for more bandwidth usage has been growing rapidly. Access network traffic is usually bursty in nature and the present traffic trend is mostly video-dominant. This motivates the need for higher transmission rates in the system. At the same time, the deployment costs and maintenance expenditures have to be reasonable. Therefore, Passive Optical Networks (PON) are considered promising next-generation access technologies. As the existing PON standards are not suitable to support future-PON services and applications, the FSAN (Full Service Access Network) group and the ITU-T (Telecommunication Standardization Sector of the International Telecommunication Union) have worked on developing the NG- PON2 (Next Generation PON 2) standard. Resource allocation is a fundamental task in any PON and it is necessary to have an efficient scheme that reduces delay, maximizes bandwidth usage, and minimizes the resource wastage. A variety of DBA (Dynamic Bandwidth Allocation) and DWBA (Dynamic Wavelength and Bandwidth Allocation) algorithms have been proposed which are based on different PONs (e.g. EPON, GPON, XG-PON, 10G- EPON, etc.). But to our knowledge, no DWBA scheme for NG-PON2 system, with diverse customers and prioritized traffic, has been proposed yet. In this work, this problem is addressed and five different dynamic wavelength and bandwidth allocation (DWBA) schemes are proposed. First, mixed integer linear programming (MILP) models are developed to minimize the total delay of the high priority data. Due to the MILP’s high computational complexity, heuristic algorithms are developed based on the MILP model insights. The five heuristics algorithms are: No Block-Split Heuristic (NBH), Equal Block-Split Heuristic (EBH), Priority Based No Block-Split Heuristic (P-NBH), Priority Based Equal Block-Split Heuristic (P-EBH), and Priority Based Decider Block-Split Heuristic (P-DBH). Six priority classes of requests are introduced with the goal of minimizing the total delay for the high priority data and to lessen the bandwidth wastage of the system. Finally, experiments for the performance evaluation of the five DWBA schemes are conducted. The results show that P-NBH, P-EBH, P-DBH schemes show a 47.63% less delay and 30% of less bandwidth wastage on average for the highest priority data transmission than the schemes without priority support (NBH and EBH). Among these five schemes, NBH method has the highest delay, whereas EBH and P-EBH waste more bandwidth than the other schemes. P-DBH is the most efficient among the five because this scheme offers the lowest delay for high priority data and the minimum bandwidth wastage for lower priority ones. Adviser: Byrav Ramamurth

Mecanismos para gerenciamento de banda passante em redes ópticas passivas Ethernet com clientes locatários de múltiplas unidades ópticas de redes

Orientador: Nelson Luis Saldanha da FonsecaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: As atuais redes de acesso banda larga à Internet necessitam dar suporte às altas demandas de diversas aplicações tais como voz sobre IP (VoIP), streaming de vídeo UHD, videoconferência, internet das coisas (IoT) e jogos interativos. A tecnologia de redes ópticas passivas (PONs) é considerada promissora para fornecer alta capacidade de acesso com um custo-benefício aceitável. Existem duas diferentes tecnologias que disputam o mercado das redes ópticas; Ethernet PON (EPON) e Gigabit Capable PON(GPON). Devido ao alto custo de aquisição e manutenção de uma infraestrutura PON, muitas empresas (clientes) recorrem a fornecedores de infraestrutura (InP) para reduzir os altos custo, por meio do aluguel de uma porção dos recursos da PON. Esses clientes podem ser, por exemplo, operadores de rede móvel ou provedores de serviços virtuais, que podem adquirir múltiplas unidades da rede óptica (ONU) conectadas em uma única PON. Essa facilidade de alugar múltiplas ONUs pode gerar problemas de balanceamento de carga entre ONUs, uma vez que os atuais algoritmos de alocação de banda passante (DBA) são capazes de garantir banda para uma única ONU. Consequentemente, picos de demanda de banda passante podem ultrapassar a banda garantida em algumas ONUs e, ao mesmo tempo, subutilizar a banda garantida em outras ONUs de um mesmo cliente. Nesta dissertação, aborda-se o problema de gerenciamento de largura de banda para clientes multi-ONU nas redes EPON. Propõe-se um algoritmo de alocação dinâmica de banda passante (DBA) (MOS-IPACT) para dar suporte ao contrato de serviço (SLA) para clientes com várias ONUs. O mecanismo proposto distribui a largura de banda agregada entre ONUs de um mesmo cliente, com o objetivo de melhorar a utilização da largura de banda. Além disso propõe-se um algoritmo DBA para EPONs (subMOSIPACT) com o objetivo de garantir banda passante em diferentes níveis de granularidade. Este algoritmo é fundamental para clientes multi-ONU e que oferecem diversos tipos de serviços. Por exemplo, um operador da rede virtual pode alugar as ONUs de um InP para oferecer serviços corporativos e residenciais. Introduz-se, também, um algoritmo DBA para EPONs (coopMOS-IPACT) que permite a cooperação entre clientes. O algoritmo proposto permite que clientes cooperativos compartilhem banda passante não utilizada a fim de aumentar a banda disponível para alocação mas sem afetar seus SLAs individuais. Os resultados mostram que os três algoritmos propostos são capazes de garantir banda passante para clientes multi-ONU, mesmo em condições de tráfego desbalanceadas; Além de garantir banda passante em diferentes níveis de granularidade aumentando o suporte aos requisitos de qualidade de serviço (QoS). Resultados derivados por simulação mostraram que os algoritmos distribuem eficientemente a largura de banda entre os clientes multi-ONU bem como para clientes convencionais que possuem uma única ONU. Por fim, este trabalho mostra os benefícios do modelo de clientes cooperativos para aumentar a largura de banda disponívelAbstract: Current broadband access networks need to support the Quality of Service (QoS) requirements of diverse application such as voice over IP (VoIP), ultra-high video streaming, video conferencing, Internet of Things (IoT) and interactive gaming. Passive Optical Networks (PONs) is considered a promising solution to provides high access capacity with acceptable cost-benefit. Two different technologies share the optical access networks market: Ethernet PON (EPON) and Gigabit Capable PON (GPON). However, the deployment of PON infrastructure involves significant costs. On the other hand, Infrastructure Provider (InP) can alleviate these costs by leasing their PONs to several enterprises (customers). These customers can be Mobile Network Operators (MNOs), multi-site enterprises, or virtual service providers. New scenarios are envisioned in which customers owning multiple Optical Network Units (ONUs) (multi-ONUs customers) are connected to a single PON. However, current EPON Dynamic Bandwidth Allocation (DBA) algorithms are able to support only guaranteed bandwidth for individual ONUs. Consequently, peaks of bandwidth demand may surpass the guaranteed bandwidth for some ONUs and, at the same time, underutilize the bandwidth in other ONUs of a multi-ONU customer. In this work, the bandwidth management problem for multi-ONU customers in EPON network is addressed. This dissertation proposes a mechanisms for the support of multiONU Service Level Agreements (SLA) in DBA algorithms for EPONs. The proposed DBA algorithms (MOS-IPACT) allows customers owning multiple ONUs to redistribute the aggregated bandwidth of the group of ONUs to better balance the bandwidth utilization. This dissertation also proposes a DBA algorithm for EPON networks (subMOS-IPACT) with the objective of assuring bandwidth at different levels of granularity. This algorithm is quite important for multi-ONU customers offering diverse type of services. For example, a virtual network operator can lease ONUs from an InP to offer enterprise and residential services to its client.This work also introduce a DBA algorithm for EPONs (coopMOS-IPACT), which allows cooperation between customers. The proposed DBA algorithm allows cooperative customers share the unused bandwidth without affecting their individual multi-ONU SLAs. Results show that the three proposed Dynamic Bandwidth Allocation (DBA) algorithms are able to guarantee bandwidth for multi-Optical Network Unit (ONU) customers even in unbalancing traffic conditions. Furthermore, assuring bandwidth at different levels of granularity improves the Quality of Service (QoS) providing. Simulation results showed that the mechanisms efficiently distributes bandwidth between multi-ONU customers and traditional customers owning a single ONU. Finally, this work show the benefits of cooperative customers model in order to increase the available bandwidthMestradoCiência da ComputaçãoMestre em Ciência da Computação132308/2016-9CNP