Integrated Wireless Backhaul Over Optical Access Networks

Recent technological advances and deployments are creating a new landscape in access networks, with an integration of wireless and fiber technologies a key supporting technology. In the past, a separation between those with fiber in the access networks and those with wireless networks, the relatively low data-rate requirements of backhaul and the relatively large cell sites, have all combined to keep fiber deployment low in wireless backhaul. As fiber has penetrated the access network and the latest wireless standards have demanded smaller, higher bandwidth cells, fiber connectivity has become key. Choices remain as to where the demarcation between key elements should be in the network and whether fiber should be used as just a high data-rate backhaul path or if a transition to radio-over-fiber techniques can afford benefits. This paper will explore the network options available in particular those demonstrated in recent European Union (EU) projects, how they can be integrated with existing access networks and how techniques such as radio-over-fiber can be deployed to offer increased functionality

Power Consumption Modeling and Analysis of Integrated Optical-Wireless Access Network

The integration of optical and wireless technologies at access networks are considered as a future solution which provide both high bandwidth and high mobility in an efficient way. GPON is a suitable candidate for optical backhaul due to the combination of higher data rates, greater split ratio and support for triple play services hence it offers maximum flexibility and cost advantages. On the other hand, recent developments of new radio access technologies and introduction of femtocell base stations provide the potential of offering broadband services and applications to everyone and everywhere. However, the power consumption of this network demands a particular attention because access networks are the largest contributor the network related electricity consumption. Therefore, in this paper we evaluate the power consumption of integrated optical-wireless access network which is based on independent ONU-BS architecture. We proposed a power consumption model for such network and the assessment has been done under different simulation scenarios. The constructed model will provide insight of the energy performance of the integrated access network so that in the network design process, focus can be done to the most energy saving strategies

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.The authors would like to acknowledge the support of the Spanish projects CRAMnet (grant no. TEC2012-38362-C03-01) and TIGRE-5CM (grant no. S2013/ICE-2919) in the development of this work. In addition, part of the cost prices in the development of the economic models come from results of the EU FP7 project DISCUS (ICT-318137).European Community's Seventh Framework Progra

How sleep modes and traffic demands affect the energy efficiency in optical access networks

An ever-increasing bandwidth demand is the main driver to investigate next-generation optical access (NGOA) networks. These networks, however, do not only have to comply with increasing data rates, but they should also meet the societal green agenda. As the access part consumes a major fraction of the energy consumption in today's fiber-to-the-home-based telecommunication networks, the energy efficiency of NGOA networks should be an important design parameter. In this paper, we present a detailed evaluation of the energy consumption in different NGOA technologies. Furthermore, we analyze the effects of (1) introducing low power modes (e.g., sleep and doze modes) in the various NGOA technologies and (2) using optimal split ratios adjusted to the traffic demands so that the energy consumption is optimized for the desired quality of service level

A comparative model and techno-economic analysis of next generation AON Ethernet and TDM PON

A global reference model covering next generation active and passive networks has been developed for techno-economic evaluations, and an extensive techno-economic analysis with a focus on CAPEX has been performed for 10G TDM PON and 1G AON - both capable of delivering 1Gbit/s to end-users. Two major cases have been considered: urban and rural at green field deployment. The results show that AON is less expensive than PON solution in urban case while in rural case 10G TDM PON is more competitive

Network Planning for Dual Residential-Business Exploitation of Next-Generation Passive Optical Networks to Provide Symmetrical 1 Gb/s Services

Demand for high-speed access for business and residential subscribers has grown rapidly in recent years; thus, service providers need to offer cost-effective solutions to cover this demand. Convergence within the same infrastructure for clients requiring different service levels may have benefits in terms of cost, but their respective service-level specifications need to be guaranteed. This article compares different flavors of next-generation passive optical networks (PONs), namely, gigabit PON (GPON), 10-gigabit PON (XG-PON), time and wavelength division multiplexing PON (TWDM-PON), and wavelength division multiplexing PON (WDM-PON), and evaluates which one can provide 1 Gb/s symmetrical service at the more affordable cost when there is a mix of residential and business subscribers. Results show that the recommended technology depends on the percentage of business subscribers in the scenario.The authors would like to acknowledge the support of the Spanish projects CRAMnet (grant no. TEC2012-38362-C03-01), Elastic Networks (grant no. TEC2015-71932-REDT), TIGRE-5CM (grant no. S2013/ICE-2919), and Fed4FIRE EU Project 318389 for the development of this work. The views expressed in this article are those of the authors and do not reflect the opinion of the authors’ employers, specifically in terms of architectural and engineering design or experience.European Community's Seventh Framework Progra

Wavelength reconfigurability for next generation optical access networks

Next generation optical access networks should not only increase the capacity but also be able to redistribute the capacity on the fly in order to manage larger variations in traffic patterns. Wavelength reconfigurability is the instrument to enable such capability of network-wide bandwidth redistribution since it allows dynamic sharing of both wavelengths and timeslots in WDM-TDM optical access networks. However, reconfigurability typically requires tunable lasers and tunable filters at the user side, resulting in cost-prohibitive optical network units (ONU). In this dissertation, I propose a novel concept named cyclic-linked flexibility to address the cost-prohibitive problem. By using the cyclic-linked flexibility, the ONU needs to switch only within a subset of two pre-planned wavelengths, however, the cyclic-linked structure of wavelengths allows free bandwidth to be shifted to any wavelength by a rearrangement process. Rearrangement algorithm are developed to demonstrate that the cyclic-linked flexibility performs close to the fully flexible network in terms of blocking probability, packet delay, and packet loss. Furthermore, the evaluation shows that the rearrangement process has a minimum impact to in-service ONUs. To realize the cyclic-linked flexibility, a family of four physical architectures is proposed. PRO-Access architecture is suitable for new deployments and disruptive upgrades in which the network reach is not longer than 20 km. WCL-Access architecture is suitable for metro-access merger with the reach up to 100 km. PSB-Access architecture is suitable to implement directly on power-splitter-based PON deployments, which allows coexistence with current technologies. The cyclically-linked protection architecture can be used with current and future PON standards when network protection is required