Efficient topology design methods for next generation access networks: Scalable network planning algorithms and cost estimation of next generation access networks
Monograph by Attila Mitcsenkov – a book version of his PhD Dissertation work, published by GlobeEdit in 2017.
Summary of all theoretical work and background of the (wired) access network design, modeling, methodology and algorithms.
Optical networks provide a future proof platform for a wide range of services at the expense of replacing the cable plant. Such an enormous investmenthas to be justified by long term sustainability. Deployment costs have to be minimized,therefore planning optimal network topology plays crucial role regarding profitability. Our novel algorithmic solutionsaim to achieve a “strategic topology design”, providing the location of the network elements, layout of the optical cable plant, and a complete system design, using available digital maps and cost databases as inputs. Our network planning methods were used in the industry with success, and the cost estimation methodology based on the achieved strategic design has outperformed traditional cost estimation solutions. Instead of time consuming human guesswork, the problem is now solved algorithmically by computers, and the algorithms scale for problem sizes of practical interest (over 10.000s of subscribers).Complexity and approximability studies, heuristics and exact algorithms are presented for minimizing cost of the network deployment, with respect to administrative requirementsand physical limitations of optical access networks.
Survivability of access networks should be reconsidered with the upcoming transition towards Fixed Mobile Convergence (FMC). In FMC networks, fixed and mobile traffic will be carried over a joint access infrastructure, increasing the risk of high impact failures that cut off all (even emergency) services. Hence, convergence brings new challenges, making the FMC network a critical infrastructure. New mechanisms are required, assuring survivability of a basic set of services (e.g. emergency services), and these solutions must respect the strong cost pressure in the access network domain by exploiting the new opportunities provided by convergence. In this paper, we propose metrics to identify the most critical failure events, and to evaluate survivability of the FMC network infrastructure. Availability requirements of typical reference services over the FMC network are discussed, and the minimal survivable subset of the FMC infrastructure is identified to avoid disruption of these services. Finally, we investigate and propose smart FMC network planning strategies and protection concepts to meet availability requirements when the use of redundancy and protection resources is very limited.
Forum & Citation
A. Mitcsenkov, T. Cinkler, F. Musumeci, A. Pattavina, “Survivability of Fixed Mobile Convergent Access Networks”, in IEEE Design of Reliable Communication Networks (DRCN) Conference 2017, Munich, Germany, Mar. 2017.
Fixed Mobile Convergence is significantly changing the role of access networks: the same infrastructure will be serving fixed broadband access, mobile macro- and small cells. It brings new challenges on the architectural level, network availability being one of the key aspects. However, the strong cost pressure in the access networks makes extensive deployment of redundancy economically infeasible. The key for affordable availability improvement is the (application specific) identification of the most critical failures. In this paper we review the main application fields of FMC networks, differentiated by its clients (residential fixed customers, mobile macro- and small cells). The most critical failures are identified for each application, and metrics are presented for evaluating failure criticality and network availability. Finally, appropriate strategies will be proposed for improving the network availability under tight cost restrictions, and the cost and availability implications will be discussed. Availability improvement not necessarily requires protection resources; diversification network planning techniques also play an important role.
Forum & Citation
17th International Conference on Transparent Optical Networks (ICTON), 2015, Budapest, Hungary
Attila Mitcsenkov, Peter Ratkoczy, Tibor Cinkler, “Minimal cost availability improvement of fixed mobile convergent (FMC) access networks: Diversification and redundancy”, ICTON 2015, Budapest, Hungary
The experienced mobile traffic increase in the recent years made traffic capacity the bottleneck instead of the coverage constraints, calling for significantly higher density of the base stations. Heterogeneous radio access networks (HetNet) provide a possible solution to this problem, combining various wireless technologies. In this paper we investigated the joint dimensioning of the co-existent radio access networks, the relation between the required macro and small cell densities to meet a certain traffic demand, and compared the two main, competing technological solutions, namely small cells and Wi-Fi, suitable to complement an LTE (macrocell) network.
heterogeneous radio access network
Forum & Citation
Péter Ratkóczy, Attila Mitcsenkov, “Joint Dimensioning of Outdoor Heterogeneous Radio Access Networks (HetNet) using Monte Carlo Simulation”, MACRo 2015, Marosvásárhely, Romania
Future generations of PON networks are likely to extend the capabilities of current TDM solutions or apply WDM technology to further increase the exploited optical bandwidth. In this paper we estimate the equipment cost difference between WDM and TDM-PONs, modeling the expected short- and mid-term changes in hardware costs, in order to find the breakeven point of TDM and WDM cost with respect to per user bandwidth. We developed a Pareto access traffic model to take into account the bandwidth gain reachable through statistical multiplexing of the shared bandwidth for TDM solutions. Our results shows that WDM variants are likely to scale better with higher bandwidths, and are expected to outperform TDM-PONs about 600 Mb/s per user speed.
Forum & Citation
Czékus József, P Megyesi, A Mitcsenkov, D Mazroa, “Hardware cost and capacity analysis of future TDM- and WDM-PON access networks”, ICTON 2014, Graz, Austria
Protection in access networks may be cost prohibitive: the availability gain may not be able to justify the necessary investment. Even though several expected (near) future applications of optical access (e.g. mobile backhaul and fixed mobile convergence, or long reach PONs with extensive node consolidation) are often cited as rationale behind access network protection, the additional investment still needs to be minimised. A key to resolve the conflict between desirable availability and the prohibitive investment is the selective deployment of redundancy. Knowing not only the architecture, but also the geographical layout of the network offers the possibility to meet global availability requirements, while protecting just a minimal subset of network elements. In this paper we investigate how far a topology-dependent selective and partial protection scheme can reduce the cost of achieving given availability levels.
Forum & Citation
G Köles, A Mitcsenkov, T Cinkler, “Topology-dependent selective and partial protection of optical access networks”, ONDM 2014, Stockholm, Sweden
Presented on European Wireless 2014, Barcelona, Spain
Stephane Gosselin, De Biasio Joseph, Feknous Moufida, Tahar Mamouni
Jose Alfonso Torrijos, Luis Cucala
Dirk Breuer, Erik Weis, Frank Geilhardt, Dirk v. Hugo, Eckard Bogenfeld
Ali Hamidian, Neiva Fonseca
Yaning Liu, Susanne Kuehrer
Jose V. Galan, Enrique Masgrau Rite
Luis Simon Gomez, Lander Alonso
The drivers of Fixed and Mobile Convergence (FMC) are discussed. A reference framework for FMC proposed by European project COMBO is then presented. Some use cases of FMC are described, showing the needs for mutualization and convergence of fixed and mobile broadband networks. Five network scenarios providing technical solutions to FMC use cases are proposed. They target an optimal and seamless quality of experience for the end user together with an optimized network infrastructure ensuring increased performance, flexibility reduced cost and reduced energy consumption.
Forum & Citation
S Gosselin et al. “Fixed and Mobile Convergence: Needs and Solutions”, European Wireless 2014, Barcelona, Spain
Access networks are responsible for a significant part of overall telecom network energy consumption. Furthermore their demand for energy also increases rapidly with the ever-growing traffic volume they carry. Sustainability necessitates energy conserving solutions which also carefully limit the negative effects on other system qualities. It is expected that future access networks are based on a converged wireless-optical architecture. This paper examines such a hybrid small cell LTE and PON network. We analyze the impact of serving the user population with a reduced number of active cells, either due to failure or selective switch-off of chosen cells. Multiple optical topologies are considered for connecting the cells of the wireless network. We use extensive simulations to quantify the interdependence of energy consumption, network availability and the QoS experienced by the consumer.
Forum & Citation
A Ladányi, T Cinkler, A Mitcsenkov, “Impact of optical access topologies onto availability, power and QoS”, DRCN 2014, Ghent, Belgium
Published in Telecommunication Systems Journal in 2013.
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.
Fibre to the home (FTTH)
Forum & citation
Telecommunication Systems Journal
Mitcsenkov, M. Kantor, K. Casier, B. Lannoo, K. Wajda, J. Chen, L. Wosinska, “Geometric versus Geographic Models for the Estimation of an FTTH Deployment”, Telecommunication Systems Journal, Vol. 54, No. 2, pp 113-127 (Oct 2013)
Next Generation Access (NGA) networks offer enormous bandwidth and low latency, mainly due to the exploitation of optical transmission. Deploying optical fiber in the access network, however, requires a huge investment, therefore optimization of the physical infrastructure plays an important role. In the recent years, algorithmic access network design became viable, mainly due to the existence of digital maps and Geographic Information System (GIS) databases. In the previous work, we have proposed technology-dependent, scalable heuristics for Passive Optical Network (PON) and Active Ethernet (AETH) network design. In this paper, we present a novel technology-independent solution based on the Simulated Annealing (SA) metaheuristics for tree-based point-to-multipoint optical access network topologies. The newly proposed heuristics deliver competitive results, within 5-10% of the theoretical optimum, even for scenarios with up to thousands of demand points. The key for scalability is the concept Voronoi-diagrams applied for demand point clustering and evaluation within the Simulated Annealing scheme.
Forum & Citation
A Mitcsenkov, P Bakos, G Paksy, T Cinkler, “Technology-independent Topology Design Heuristics for Point-to-Multipoint Optical Access Networks”, ONDM 2013, Brest, France