Automatic map-based FTTx access network design

Several mature and standardized optical access network technologies are available for network operators providing broadband services, being now in deployment phase; therefore cost estimation, business analysis, efficient deployment strategies, network and topology design issues for FTTx access networks play an increasingly important role regarding profitability and market success. In a competitive environment, techno-economic evaluation supports the optimal choice among available technologies. Even the tradeoff between future proof technical superiority and short term investment minimization requires a farseeing decision. In our point of view, cost estimation and techno-economic evaluation is strongly related to strategic network design: among others the uneven population density, irregular street system or infrastructure have significant impact on the network topology, thus the deployment costs as well. In order to deal with these aspects, a high-level, strategic network design is necessary that adapts to geospatial characteristics of the services area, providing accurate and detailed network information for the techno-economic evaluation [1]. We have developed a topology designer methodology that supprts the above requirements, providing (near) optimal topology of the fully or partially optical access network, based on the geospatial information about the service area: digital maps, existing infrastructure and subscriber database. Automatic topology design for large-scale service areas, with 10.000s of subsribers is a highly complex mathematical problem. The tough algorithms for a near optimal, yet efficient solution. The developed algorithms were evaluated regarding their speed and accuracy. Based on topology design results, a detailed and flexible techno-economic comparison is carried out, since the framework handles various broadband access network technologies, as presented in a case study. --Topology design,Strategic Design,Network planning,GIS,Map,Techno-economic,Cost estimation

Algorithm of optimal technology selection of broadband access network

High speed applications require the access network upgrading based on new optical technologies in “last mile”. At the planning stage of network modernization, special algorithms and techniques allow optimize and automate the designing process of network upgrade based on copper cables. However, these techniques are completely inapplicable if optical technologies are used to the access network modernization. Designed algorithm simplifies the throughput calculation of current access nodes and planning of new access nodes depending on subscriber’s requirementstto the broadband services. Developed program based on proposed algorithm allows to determinate access nodes optimal deployment as well as the required equipment characteristics

Geometric versus geographic models for the estimation of an FTTH deployment

Optical access networks provide a future proof platform for a wide range of services, and today, several operators are deploying fibre to the home (FTTH) networks. Installing an FTTH infrastructure, however, involves very high investment cost. Therefore, a good estimation of the investment cost is important for building a successful business strategy and, consequently, to speed up the FTTH penetration. In this paper, for calculating the amount of cable and fibre in the outside plant together with the associated civil works, and the number of required network elements, two different approaches are investigated: (1) geometric modelling of the fibre plant based on approximate mathematical models and (2) geographic modelling of the fibre plant based on map-based geospatial data. The results obtained from these two approaches can then be used as input for preliminary investment cost calculations and/or techno-economic evaluations. Compared to more complex and accurate geographic modelling, we verify that especially with uneven population density and irregular street system, simple geometric models do not provide accurate results. However, if no geospatial data is available or a fast calculation is desired for a first estimation, geometric models definitely have their relevance. Based on the case studies presented in this paper, we propose some important guidelines to improve the accuracy of the geometric models by eliminating their main distortion factors

Cost-Effective Delay-Constrained Optical Fronthaul Design for 5G and Beyond

With the rapid growth of the telecom sector heading towards 5G and 6G and the emergence of high-bandwidth and time-sensitive applications, mobile network operators (MNOs) are driven to plan their networks to meet these new requirements in a cost-effective manner. The cloud radio access network (CRAN) has been presented as a promising architecture that can decrease capital expenditures (Capex) and operating expenditures (Opex) and improve network performance. The fronthaul (FH) is a part of the network that links the remote radio head (RRH) to the baseband unit (BBU); these links need high-capacity and low latency connections necessitating costeffective implementation. On the other hand, the transport delay and FH deployment costs increase if the BBU is not placed in an appropriate location. In this paper, we propose an integer linear program (ILP) that simultaneously optimizes BBU and FH deployment resulting in minimal capital expenditures (Capex). Simulations are run to compare the performance of star and tree topologies with the varying line of sight probabilities (LoS) and delay thresholds. We consider fiber-optic (FO) and free-space optics (FSO) technologies as FH for the CRAN. Finally, we provide an analysis of Opex and the total costs of ownership (TCO), i.e., a technoeconomic analysis

Switching Equipment Location/Allocation in hybrid PONs

Our research goal is to investigate the FTTX (Fiber-to-the Home/Premises/Curb) passive optical network (PON) for the deployment of BISAN (Broadband Internet Subscriber Access Network) to exploit the opportunities of optical fiber enabled technologies as well as of passive switching equipment. Indeed, the deployment of FTTX PON is the most OPEX-friendly scenario, because it allows for completely passive access networks through minimizing the number of active components in the network. Previously, most FTTX PON architectures are designed based on the principle of either time division multiplexing (TDM) technology or wavelength division multiplexing (WDM) technology. We focus on designing the best possible architectures of FTTX PON, specifically hybrid PONs, which embraces both TDM and WDM technology. A hybrid PON architecture is very efficient as it is not limited to any specific PON technology, rather it is flexible enough to deploy TDM/WDM technology depending on the type (i.e unicast/multicast) and amount of traffic demand of the end-users. The advantages of a hybrid PON are of two folds: (i) it can offer increased data rate to each user by employing WDM technology, (ii) it can provide flexible bandwidth utilization by employing TDM technology. In this thesis, we concentrate on determining the optimized covering of a geographical area by a set of cost-effective hybrid PONs. We also focus on the greenfield deployment of a single hybrid PON. It should be worthy to mention that while investigating the deployment of hybrid PONs, the research community around the world considers the specifications of either the physical layer or the optical layer. But an efficient planning for PON deployment should take into account the constraints of the physical and optical layers in order that both layers can work together harmoniously. We concentrate our research on the network dimensioning and the selection as well as the placement of the switching equipment in hybrid PONs with the intention of considering the constraints of both physical and optical layers. We determine the layout of an optimized PON architecture while provisioning wavelengths in a hybrid PON. We also propose to select the switching equipment depending on the type (unicast/multicast) of traffic demand. Finally, we determine the best set of hybrid PONs along with their cascading architecture, type and location of their switching equipment while satisfying the network design constraints such as the number of output ports of the switching equipment and maximum allowed signal power loss experienced at each end user’s premises. In this thesis, we propose two novel schemes for the greenfield deployment of a single hybrid PON. The first scheme consists of two phases in which a heuristic algorithm and a novel column generation (CG) based integer linear programming (ILP) optimization model are proposed in the 1st and 2nd phase respectively. In the second scheme, a novel integrated CG based ILP cross layer optimization model is proposed for the designing of a single hybrid PON. We also propose two novel schemes to deal with the greenfield deployment of multiple hybrid PONs in a given geographical area. These two schemes determine the best set of cost-effective hybrid PONs in order to serve all the end users in a given neighborhood. The first scheme executes in four phases in which two heuristic algorithms, a CG based ILP model and an ILP optimization model are proposed in the 1st, 2nd, 3rd and 4th phase respectively. In the second scheme, an ILP model as well as a CG based ILP model, another ILP model as well as another CG based ILP model, a CG based ILP model and an ILP optimization model are proposed during four consecutive phases. Our proposed scheme can optimize the design of a set of hybrid PONs covering a given geographic area as well as the selection of the best cascading architecture 1/2/mixedstage) for each selected PON. It minimizes the overall network deployment cost based on the location of the OLT and the ONUs while granting all traffic demands. The scheme emphasizes on the optimum placement of equipment in a hybrid PON infrastructure due to the critical dependency between the network performances and a proper deployment of its equipment, which, in turn depends on the locations of the users. It is a quite powerful scheme as it can handle data instances with up to several thousands ONUs. On the basis of the computational results, the proposed scheme leads to an efficient automated tool for network design, planning, and performance evaluation which can be beneficial for the network designers