Generation Access Networks Research Articles

The Power Quality of the distribution networks and its impact on the Telecommunication Next Generation Access Network

The paper deals with the Power Quality of the electrical distribution network and its impact on the new telecommunication networks. In particular, in the frame of the deployment of the Next Generation Access Network (NGAN) in the Fiber To The Cabinet (FTTCab) architecture, the impact of severe voltage dips and micro interruptions on the most important Information and Communications Technology (ICT) devices has been evaluated experimentally by Telecom Italia, defining in particular a sort of customized voltage dips immunity area for its telecommunications network equipment (TLC). On the base of these experimental results RSE has performed statistical analyses on voltage dips occurring outside this area which could be responsible in theory for the telecommunication devices reboot. The analyses are based on the data provided by the MV distribution network monitoring system QuEEN in the assumption that MV dips could be totally transferred to the LV network where the telecommunication cabinets are connected. A short analysis of voltage dips propagation from the medium voltage MV to the low voltage LV networks has been performed, on a few measurements sites at disposal in order to confirm this assumption.

Role of next generation access networks on COVID-19 propagation: Empirical assessment with a dynamic multinomial discrete choice model framework

Through the application of discrete choice and machine learning models, the primary objective of this study is to assess the impact of NGA networks coverage on reducing the risk of contagion during the first wave of COVID-19 across 278 municipalities in mainland Portugal, while controlling for other domains under the tutelage of the local public administration. Benchmark estimations reveal that, while holding everything else constant, each spatial unit is 2.4 p.p. more likely to become a high-risk municipality with additional 10 ​000 cabled houses with NGA networks. In a multinomial discrete choice model setting, the technical novelty of this study lies in providing graphical visualization and economic interpretation of coefficients and average marginal effects as a function of the number of classes used to define the dependent variable, while ensuring the satisfaction of the IIA assumption. The positive and significant coefficients of NGA indicate that additional coverage of NGA networks increases the likelihood of municipalities becoming high-risk for increasing number of spatial units not belonging to the low-risk efficiency frontier. The significant, negative, and decreasing average marginal effects of NGA suggest that the ability to remain a low-risk municipality diminishes with increasing NGA networks coverage as the number of municipalities belonging to the low-risk efficiency frontier decreases. The analysis also confirms that the effect of NGA networks coverage on COVID-19 is statistically significant in the indirect channel. This impact persists due to the mediation of population density, which is directly influenced by NGA networks coverage. All these findings can be explained by the fact that benefits related to productive activities do not outweigh costs associated with leisure time. Hence, this research emphasizes the need for a normative discussion on the intended purpose of digital technologies built on top of NGA networks to ensure a level playing field in the post-pandemic era.

Design and performance evaluation of next generation access network based on advanced optical carrier generator

Abstract Passive optical network (PON) was designed in this paper. The design aim was to locate faulty line of service professionally without extra effort. In the literature, there were various PON-design methodologies. However, a design with fewer components and less faulty line tracking was a challenge. The suggested approach tried to overcome the leakage in the state-of-the-art, such that, the PON network would be able to serve forty-eight optical network units (ONUs). At the same time, the design has to have the capability to distinguish the dropped line of service straightforwardly. The design in this thesis mainly depends on the fiber Bragg gratings (FBGs) to create six-groups, in each group, there are eight-branches. Each branch serves as an end-user/customer point. The capacity of fault location was achieved for ONUs distanced/located as far as 20 Km from the central office (CO). There was only one optical spectrum analyser (OSA) inside the CO. This OSA employed to monitor the whole network groups, i.e., forty-eight branches/ONU were screened inside the CO to predict the fault location. The system is built using the OptiSystem software package version 14.

Network modeling approaches for calculating wholesale NGA prices: A full comparison based on the Greek fixed broadband market

According to the European Commission Recommendation for setting copper and fiber wholesale prices where cost orientation is imposed as a remedy, National Regulatory Authorities (NRAs) should adopt a Bottom-UP Long-Run Incremental Cost Plus (BU LRIC+) costing methodology that estimates the current cost that a hypothetical efficient operator would incur to build a modern efficient Next Generation Access (NGA) network. The starting point of modeling an efficient operator investing in NGA networks is the network modeling approach. In this paper, we compare the most widely adopted network modeling approaches in terms of wholesale fiber-to-the-home (FTTH) prices. In particular, the modified scorched node approach is compared to the extreme cases of the scorched node and the scorched earth approaches. The comparison between the aforementioned scenarios sheds light on the impact of each approach on the wholesale FTTH prices. The main finding of this paper is that the scorched earth approach leads to a maximum of 10% reduction in the short-term access prices compared to the most inefficient scorched node approach, whereas further extending its optimizations by optimizing the number of central offices, both the short-term and long-term wholesale price reductions are quite significant (more than 20%) regardless of service speeds. Consequently, NRAs should consider a geographically differentiated modeling approach when regulating the wholesale market by adjusting the level of scorching in each area and network segment according to the investment plans of telecom operators. An appropriate variation of the modeled network operator's efficiency is expected to more accurately represent the costs of a reasonably efficient operator based on the real market conditions and a forward-looking perspective. These findings provide valuable information to both network operators and telecom regulators.

Frequency sextupling millimeter wave generation by using lithium niobate mach zehnder modulator without an optical amplifier

The millimeter wave (mmw) based optical networks have been considered as the most promising solution to increase the capacity, coverage, bandwidth and decreasing cost for next generation access networks. The optical fiber technology utilizing mmw band is an attractive way to provide higher signal bandwidth and overcome congestion. In the present era the frequency having less bandwidth is used in the communication technology which increases the time delay. The proposed scheme is used to generate mmw with an applied voltage of 7 V for a distance of 50 km and data rate of 6 Gbps is achieved by using a Lithium niobate Modulator without an optical amplifier and filter. The carrier suppression scheme used in the LiNbO3 modulator act as a optical filter so that the complexity of the system is reduced. As the modulator helps to increase the frequency of the input signal to achieve a long distance transmission through an single mode optical fiber the number of optical amplifiers can also be reduced. To verify the robustness of the setup the visualizers are used which ensure the data quality.

Regional differences in residential demand for very high bandwidth broadband internet in 2025

The future demand for data and the role of gigabit networks are central issues in the context of Next Generation Access (NGA) network roll-out. Based on a generic model, which allows to predict unconstrained future broadband demand in different regions and countries, the authors compare the results for Germany, the UK and the Flemish region, and discuss reasons for the different outcomes. The generic market potential model thereby allows to project the future demand for bandwidth from residential customers on the basis of applications and their bandwidth needs, user profiles and population structure on a household level. Despite a general trend towards an increasing need for broadband, there are clear differences. On the one hand, these point to the relevance of socio-demographic factors for broadband adoption. On the other hand, the relatively high proportion of refusals shows that there is still a need for further educational work on the part of public authorities and providers. Finally, it has to be stated, that our forecast relies on the assumption that connectivity and thus that the availability of area-wide gigabit capable broadband access does not represent a bottleneck.

Versatile Externally Modulated Lasers Technology for Multiple Telecommunication Applications

This paper presents our technological approach for Externally Modulated Lasers (EMLs), based on Semi-Insulating Buried Heterostructure (SIBH) waveguide. We use Gas Source Molecular Beam Epitaxy (GSMBE) to grow the Phosphorus-based multi-quantum wells for both laser and modulator sections with butt-joint integration. The same GSMBE grows the p-doped InP claddings with low-diffusion Be dopant, leading to an accurate control of doping profiles, ensuring very steep modulator extinction curves. We present the main EML design rules and compromises, then apply them to different EMLs aiming at major telecom and datacom applications. After presenting characteristics of the standard 10 Gb/s C-band EML, we propose a 10 Gb/s EML at 1577 nm for next generation access networks, with a record high 10.5 dBm facet modulated power. Then we present high-speed EMLs up to 56 GBaud for datacenter interconnections, both in O- and C-band, aiming at very low peak-to-peak modulation voltage (<; 1.2 V), high facet modulated power (> 4.4 dBm), and compatible with uncooled operation (20 to 70 °C). These results confirm the efficiency and versatility of this technological platform for EMLs in a broad range of applications.

Investigating the intertwining impact of wholesale access pricing and the commitment to net neutrality principle on European next-generation access networks private investment plans: An options-game application for capturing market players' competitive interactions

Whilst the deployment of next generation access networks (NGANs) is undoubtedly beneficial to the economy, new legal developments in the United States (US) regarding the issue of net neutrality (NN) pose a new challenge not only to policy makers but to telecommunication providers as well, that could justify a fresh approach when assessing NGANs investments. In particular, the Federal Communications Commission (FCC) subverted extant NN rules in the US and if the European Union (EU) decides to follow a similar deregulatory path in the future it could change the way telecommunications providers on both sides of the Atlantic lay down their optical-fibre network infrastructure investment plans. For instance, if traffic prioritization is allowed then diversification of revenue sources can be achieved by charging customers for privileged data delivery to their premises. Currently, NGANs roll-out throughout EU is an ongoing process in a setting whereby access regulation in the form of network element unbundling is already imposed. As a result, these legal developments form a new context within which it makes sense to assess the role of NGANs wholesale access pricing in tandem with the degree of commitment to NN rules so as to i) determine their combinatorial impact on private telecommunications operators' financial figures and ii) capture their competitive interactions. Towards this end, an important aspect of particular value to market players (i.e. incumbents and competitive providers – CPs), and policy makers (i.e. National Regulatory Authorities – NRAs) that this article aims to examine is how to employ the option-game (OG) analysis, that reflects the intersection of game theory (GT) and real options (ROs), to model the competitive interactions between participants in a particular competition game set-up by means of deriving possible Nash-equilibrium (NE) outcomes within a regulatory setting part of which is the commitment or non-commitment to the NN principle. This, hybrid, evaluation tool is applied on top of a conventional discounted cash flow (DCF) techno-economic analysis assessment of an NGAN investment opportunity.

High Power-over-Fiber Feed for Radio-over-Fiber Systems with Remote Antenna Units

We experimentally demonstrated a radio-over-fiber transmission integrated with a power-over-fiber system for next generation access networks, which can drive remote antenna units and improve bandwidth utilization effectively. We have achieved high transmission performance and expanded the signal transmission capacity.

Efficient Algorithms for Coded Multicasting in Heterogeneous Caching Networks.

Coded multicasting has been shown to be a promising approach to significantly improve the performance of content delivery networks with multiple caches downstream of a common multicast link. However, the schemes that have been shown to achieve order-optimal performance require content items to be partitioned into several packets that grows exponentially with the number of caches, leading to codes of exponential complexity that jeopardize their promising performance benefits. In this paper, we address this crucial performance-complexity tradeoff in a heterogeneous caching network setting, where edge caches with possibly different storage capacity collect multiple content requests that may follow distinct demand distributions. We extend the asymptotic (in the number of packets per file) analysis of shared link caching networks to heterogeneous network settings, and present novel coded multicast schemes, based on local graph coloring, that exhibit polynomial-time complexity in all the system parameters, while preserving the asymptotically proven multiplicative caching gain even for finite file packetization. We further demonstrate that the packetization order (the number of packets each file is split into) can be traded-off with the number of requests collected by each cache, while preserving the same multiplicative caching gain. Simulation results confirm the superiority of the proposed schemes and illustrate the interesting request aggregation vs. packetization order tradeoff within several practical settings. Our results provide a compelling step towards the practical achievability of the promising multiplicative caching gain in next generation access networks.

Cost effective OLT arrangements in 40 Gbps WDM-PON using AWG with a single laser

In this paper, we upgraded the optical line terminal (OLT) of the optical access network for 40 Gbps by proposing a cost effective OLT based on cascaded model of phase modulator and arrayed waveguide grating for wavelength division multiplexed passive optical network (WDM-PON). The conventional setup at OLT side of WDM-PON system is replaced with a new arrangement containing single laser source in cascade with phase modulator and AWG, whereas the phase modulator is tailored with RF source. The phase modulator generates multicarrier signal and AWG splits the signal into multiple single wavelengths based on its routing configurations. AWG is actually used as a passing band periodical filter that routs the input wavelengths to four outputs depending on its free spectral range. Across each routed wavelength, differential phase shift keying is used in downlink transmission for 10 Gbps, while intensity modulation is employed in the uplink transmission based on off-keying. 40 Gbps full duplex transmission via 20 km fibre span is successfully achieved with minimum power loss and effective results. Transmission performances are examined with negligible power penalties, better Q-factors, handsome eye openings and good eye heights, which confirm the deployment of proposed arrangement in the next generation access network.

High-priority first dynamic wavelength and bandwidth allocation algorithm in TWDM-PON

Abstract Time and wavelength division multiplexing passive optical network (TWDM-PON) is the mainstream scheme of the next generation access network, and it possesses a number of unique characteristics such as high-bandwidth, long-distance data transmission, and connecting lots of users. As the difference among user traffic demands increases, in order to effectively decrease the network delay and improve resource utilization, a high-priority first dynamic wavelength and bandwidth allocation (HF-DWBA) algorithm in TWDM-PON system is proposed in this study. According to the service-level agreement (SLA), in order to determine the priority of an optical network unit (ONU), the proposed algorithm ensures the high-level ONU traffic distribution in terms of wavelength assignment and bandwidth allocation, and it can execute five types of transmission containers (T-CONTs) as well as four kinds of bandwidth allocation strategies. The results of simulation show that in comparison with traditional algorithms, the proposed HF-DWBA algorithm can effectively reduce end-to-end time delay and improve bandwidth utilization ratio, while making fairness among different types of bandwidth allocation strategies.

Proposing simulation model for multi‐wavelength source offering 40 Gbps WDM‐PON using AWG with a single laser

AbstractIn this paper, A new simulation model is proposed and implemented for cost effective optical line terminal (OLT) arrangements for wavelength division multiplexed passive optical network (WDM‐PON). The conventional setup at OLT side is replaced with a new arrangement containing single laser source in cascade with phase modulator and arrayed waveguide grating (AWG), whereas the phase modulator is tailored with one RF source. The phase modulator generates multicarrier signal and AWG splits the signal into multiple single wavelengths based on its routing configurations. AWG is actually used as a passing band periodical filter that routs the input wavelengths to four different wavelengths depending on its free spectral range, the frequency spacing between the generated wavelengths is 20 GHz. Across each routed wavelength, differential phase shift keying is used in downlink transmission for 10 Gbps, while intensity modulation is employed in the uplink transmission based on off‐keying. 40 Gbps full duplex transmission via 20 km fiber span is successfully achieved with minimum power loss and effective results. At ONU side, optical splitters divides the signal into two, half power of the signal is used in demodulation at ONU while half of the power is utilized for the uplink transmission, this way colorless transmission is achieved. Transmission performances are examined with negligible power penalties, better Q‐factors, and handsome eye openings, which confirm the deployment of proposed arrangement in the next generation access network. The proposed model is successfully implemented in the simulation environment provided by OptiSystem.

Communication and computation cooperation in cloud radio access network with mobile edge computing

Cloud radio access network (C-RAN) and mobile edge computing (MEC) have emerged as promising candidates for the next generation access network techniques. Unfortunately, although MEC tries to utilize the highly distributed computing resources in close proximity to user equipments (UE), C-RAN suggests to centralize the baseband processing units (BBU) deployed in radio access networks. To better understand and address such a conflict, this paper closely investigates the MEC task offloading control in C-RAN environments. Most prior work handling offloading control falls in the general category of resource allocation optimization. However in this paper, we focus on the perspective of matching problem. Our model smartly captures the unique features in both MEC and C-RAN with respect to communication and computation efficiency constraints. We divide the cross-layer optimization into the following three stages: (1) matching between remote radio heads (RRH) and UEs, (2) matching between BBUs and UEs, and (3) matching between mobile clones (MC) and UEs. By applying the Gale-Shapley Matching Theory in the duplex matching framework, we propose a multi-stage heuristic to minimize the refusal rate for user’s task offloading requests. Trace-based simulation confirms that our solution can successfully achieve near-optimal performance in such a hybrid deployment.

Joint Energy Minimization and Resource Allocation in C-RAN with Mobile Cloud

Cloud radio access network (C-RAN) has emerged as a potential candidate of the next generation access network technology to address the increasing mobile traffic, while mobile cloud computing (MCC) offers a prospective solution to the resource-limited mobile user in executing computation intensive tasks. Taking full advantages of above two cloud-based techniques, C-RAN with MCC are presented in this paper to enhance both performance and energy efficiencies. In particular, this paper studies the joint energy minimization and resource allocation in C-RAN with MCC under the time constraints of the given tasks. We first review the energy and time model of the computation and communication. Then, we formulate the joint energy minimization into a non-convex optimization with the constraints of task executing time, transmitting power, computation capacity and fronthaul data rates. This non-convex optimization is then reformulated into an equivalent convex problem based on weighted minimum mean square error (WMMSE). The iterative algorithm is finally given to deal with the joint resource allocation in C-RAN with mobile cloud. Simulation results confirm that the proposed energy minimization and resource allocation solution can improve the system performance and save energy.

Fiber deployment in Spain

Next generation access networks will be critical for future economic growth and access to these infrastructures will have major consequences for territorial and social cohesion. This paper examines the economic and competition determinants that serve as incentives for operators to invest in fiber-to-the-home technology. We draw on a dataset comprising 6603 Spanish municipalities with access to broadband services to examine the incumbent’s (Telefonica) deployment of fiber in the period 2010–2013. We show that local loop unbundling competition had a strong positive impact on Telefonica’s fiber deployment, while bitstream competition had a negative effect. Moreover, the incumbent was more likely to invest in municipalities with a large presence of cable operators. We also consider how the municipalities’ sociodemographic characteristics affected the operator’s deployment decision. While market size and population density had a positive effect on investment, the level of unemployment and the percentage of elderly population had a negative impact.

Anatomy of a public-private partnership: Hold-up and regulatory commitment in Ultrafast Broadband

In recent years, the preference for purely private funding and ownership of telecommunications networks has given way to a ‘new wisdom’ that some form of public funding is now likely necessary if faster and more capacious next generation access (NGA) networks are to be constructed in a timely fashion for the majority of the population. Policy-makers are charged with deciding how that public investment will take place. One approach is via Public-Private Partnerships (PPPs), where public and private actors collaborate in UFB (Ultrafast Fibre Broadband) investment, construction and operation. However, the body of analysis of PPPs in NGA networks to guide policy-makers is scant.By using the concept of regulatory commitment, the paper compares the experiences gained in a hold-up situation in PPPs in other infrastructures (e.g. roading) with the UFB context. A case study of New Zealand's Ultrafast Fibre Broadband Initiative is used to draw new insights for government purchasers and regulatory agencies. In comparing the different forms of PPPs, the paper shows that UFB PPPs reverse the typical direction of financing and ownership observed in roading PPPs. Financing and asset ownership are separated in UFB PPPs, increasing the potential for misalignment of incentives and the likelihood that the public party can use its legislative powers to alter regulatory settings after the PPP contract is signed, and thereby hold up the private party once existing network assets are sunk. Whilst the government instigating the PPP may not be inclined to act opportunistically, a successive government facing different political priorities does not face the same incentives. To the extent that the private party can anticipate this risk, it should structure the initial agreement to ensure that the public party is penalised if such an event occurs (i.e. an automatic right to favourable renegotiation or payment of compensation). Such terms will discourage opportunism, so that the project benefits from time-consistent alignment of incentives and objectives.

Next Generation Access Network Deployment in Croatia: Optical Access Networks and Current IoT/5G Status

ABSTRACTThis paper gives an overview and background of optical access network deployment in Croatia. Optical access network development in Croatia has been put into a global as well as in the European Union context. All the challenges and the driving factors for optical access networks deployment are considered. Optical access network architectures that have been deployed by most of the investors in Croatian telecommunication market are presented, as well as the architectures that are in early phase of deployment. Finally, an overview on current status of mobile networks of the fifth generation and Internet of Things is given.

Queue-Aware Dynamic Placement of Virtual Network Functions in 5G Access Network

With the development of network function virtualization technology, virtual network functions (VNFs) can be chained to provide different services for users in fifth generation access networks. Under the condition of a large number of various user service requests reach the network in a short time, dynamic placement of VNFs is essential to achieve efficient physical resource allocation, while ensuring network stability. Unlike queue models in current works, we design a dynamic scheduling model of two-stage queue to perceive the status of current queue backlog and schedule the queue dynamically. In particular, we formulate a VNF placement cost minimization problem, taking the network stability into account. Owing to that the problem belongs to an NP-hard problem, we transform it into the minimization of the upper bound of the drift-plus-penalty function by the Lyapunov optimization technique. Then, we decompose the reformulated problem into a service function chain (SFC) scheduling problem and an SFC mapping problem, corresponding to our designed dynamic scheduling model of two-stage queue. For the above-mentioned two problems, we present a queue-aware dynamic placement of virtual network functions algorithm. It includes a genetic algorithm-based heuristic SFC scheduling algorithm (first stage) and a genetic algorithm-based heuristic SFC mapping algorithm (second stage). Simulation results demonstrate that our placement algorithm can guarantee less placement cost while significantly enhancing network stability, compared with the existing algorithm.

The Deployment of Next Generation Access Network in the EU: Facts and Analysis of Regulatory Issues

The Deployment of Next Generation Access Network in the EU: Facts and Analysis of Regulatory Issues