Sharing gNB components in RAN slicing: A perspective from 3GPP/NFV standards

To implement the next Generation NodeBs (gNBs) that are present in every Radio Access Network (RAN) slice subnet, Network Function Virtualization (NFV) enables the deployment of some of the gNB components as Virtual Networks Functions (VNFs). Deploying individual VNF instances for these components could guarantee the customization of each RAN slice subnet. However, due to the multiplicity of VNFs, the required amount of virtual resources will be greater compared to the case where a single VNF instance carries the aggregated traffic of all the RAN slice subnets. Sharing gNB components between RAN slice subnets could optimize the trade-off between customization, isolation and resource utilization. In this article, we shed light on the key aspects in the Third Generation Partnership Project (3GPP)/NFV standards for sharing gNB components. First, we identify four possible scenarios for sharing gNB components. Then, we analyze the impact of sharing on the customization level of each RAN slice subnet. Later, we determine the main factors that enable isolation between RAN slice subnets. Finally, we propose a 3GPP/NFV-based description model to define the lifecycle management of shared gNB componentsThis work is partially supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (Project TEC2016-76795-C6-4-R)Spanish Ministry of Education, Culture and Sport (FPU Grant 17/01844)Andalusian Knowledge Agency (project ATIC-241-UGR18)

Analytical Model for the UE Blocking Probability in an OFDMA Cell providing GBR Slices

This work is partially supported by the H2020 research and innovation project 5G-CLARITY (Grant No. 871428); the Spanish Ministry of Economy and Competitiveness, the European Regional Development Fund (Project PID2019-108713RB-C53); and the Spanish Ministry of Education, Culture and Sport (FPU Grant 17/01844).When a network operator designs strategies for planning and operating Guaranteed Bit Rate (GBR) slices, there are inherent issues such as the under(over)-provisioning of radio resources. To avoid them, modeling the User Equipment (UE) blocking probability in each cell is key. This task is challenging due to the total required bandwidth depends on the channel quality of each UE and the spatio-temporal variations in the number of UE sessions. Under this context, we propose an analytical model to evaluate the UE blocking probability in an Orthogonal Frequency Division Multiple Access (OFDMA) cell. The main novelty of our model is the adoption of a multi-dimensional Erlang-B system which meets the reversibility property. This means our model is insensitive to the holding time distribution for the UE session. In addition, this property reduces the computational complexity of our model due to the solution for the state transition probabilities has product form. The provided results show that our model exhibits an estimation error for the UE blocking probability below 3.5%.This work is partially supported by the H2020 research and innovation project 5G-CLARITY (Grant No. 871428)Spanish Ministry of Economy and Competitiveness, the European Regional Development Fund (Project PID2019-108713RB-C53)Spanish Ministry of Education, Culture and Sport (FPU Grant 17/01844

Empleo de tres constelaciones de viviendas para innovar dentro del aula de dibujo

[EN] This text presents the findings resulting from a teaching innovation experience that begins in the 2021-2022 academic year, continues in 2022-2023 and extends in 2023-2024. The experiment, carried out during the fourth semester of the degree in fundamentals of architecture at the University of Alicante and through an architectural drawing subject, consists of blurring the boundaries between the profession and the academic world through the collaboration of the intervening agents, namely students, teachers and Spanish architects of recognized prestige. Thus, starting from a series of meetings and interactive intersections in the form of conferences, round tables and interviews, a working methodology is proposed in which the student, aware of his active role in understanding and interpreting the graphic, has the opportunity to synthesize the skills and abilities acquired in a format that, although exclusively graphic, in most cases exceeds the starting content. Three housing constellations, one per academic year, will be the vehicle to put into play constant self-evaluation, active participation, the search for radicality or conscious innovation by the aforementioned agents. Always around an element common to all contexts: the image.[ES] El presente texto expone los hallazgos resultados de una experiencia de innovación docente que se inaugura en el curso académico 2021-2022, continúa en el 2022-2023 y se extiende en el 2023-2024. El experimento, realizado durante el cuarto semestre del grado en fundamentos de la arquitectura de la Universidad de Alicante y a través de una asignatura de dibujo arquitectónico, consiste en difuminar los límites entre la profesión y el mundo académico mediante la colaboración de los agentes intervinientes, a saber, discentes, docentes y arquitectas y arquitectos españoles de reconocido prestigio. Así, partiendo de una serie de encuentros e intersecciones interactivas en forma de conferencias, mesas redondas y entrevistas, se propone una metodología de trabajo en la que el discente, consciente de su papel activo a la hora de comprender e interpretar lo gráfico, tiene la oportunidad de sintetizar las competencias y capacidades adquiridas en un formato que, aunque exclusivamente gráfico, en la mayoría de los casos excede los contenidos de partida. Tres constelaciones de viviendas, una por curso académico, serán el vehículo para poner en juego la constante autoevaluación, la participación activa, la búsqueda de la radicalidad o la consciente innovación por parte de los citados agentes. Siempre en torno a un elemento común a todos los contextos: la imagen.Navarro Jover, L.; Juan Gutiérrez, PJ.; López Ujaque, JM. (2023). Use of three housing constellations to innovate within the drawing classroom. EGE Revista de Expresión Gráfica en la Edificación. (19):37-50. https://doi.org/10.4995/ege.2023.2070337501

Tiempo de fotogrametría. Una propuesta de clasificación para el levantamiento fotogramétrico

The graphic survey of the built heritage allows and makes possible a graphic territory of learning, analysis, experimentation, communication and deposit for architecture. It supposes, in addition to the connection between the theory and the practice of our discipline, an excellent framework for teaching. In this context, photogrammetry is evidenced as a rigorous and efficient technique that, at the service of relevant hypotheses, is capable of producing results that are as valuable as they are contemporary. This research paper, created after the tutelage of more than forty final degree projects that use the photogrammetric technique, develops a classification proposal for qualified point clouds (as part of the technique workflow) based on the temporal nature of the drawings. In this way we will argue the three possible positions (previous or tool, intermediate or process and later or result) to conclude by claiming the relevance and importance of their consideration during the value of the drawings of the built architecture.El levantamiento del patrimonio construido permite y hace posible un territorio gráfico de aprendizaje, análisis, experimentación, comunicación y depósito para la arquitectura. Supone, además de la conexión entre la teoría y la práctica de nuestra disciplina, un marco inmejorable para la enseñanza. En este contexto la fotogrametría se evidencia como una técnica rigurosa y eficaz que, al servicio de unas hipótesis pertinentes, es capaz de producir resultados tan valiosos como contemporáneos. El presente artículo de investigación, producido tras la tutela de más de cuarenta trabajos finales de grado que emplean la técnica fotogramétrica, desarrolla una propuesta de clasificación para las nubes de puntos cualificados (parte del flujo de trabajo de la técnica) atendiendo al carácter temporal de la grafía. De esta forma argumentaremos las tres posibles posiciones (anterior o herramienta, intermedia o proceso y posterior o resultado) para concluir reivindicando la pertinencia e importancia de su consideración durante la puesta en valor de los dibujos de la arquitectura construida.This work is developed as part of an R+D+I project entitled “The representation of time in graphic expression”, with reference project-emergent-GRE18-10 and funded, in public concurrence, by the Vice-Rector’s Office for Research and Transfer of Knowledge of the University of Alicante

Analytical Modeling and Experimental Validation of NB-IoT Device Energy Consumption

The recent standardization of 3GPP Narrowband Internet of Things (NB-IoT) paves the way to support low-power wide-area (LPWA) use cases in cellular networks. NB-IoT design goals are extended coverage, low power and low cost devices, and massive connections. As a new radio access technology, it is necessary to analyze the possibilities NB-IoT provides to support different traffic and coverage needs. In this paper, we propose and validate an NB-IoT energy consumption model. The analytical model is based on a Markov chain. For the validation, an experimental setup is used to measure the energy consumption of two commercial NB-IoT user equipments (UEs) connected to a base station emulator. The evaluation is done considering three test cases. The comparison of the model and measurements is done in terms of the estimated battery lifetime and the latency needed to finish the control plane procedure. The conducted evaluation shows the analytical model performs well, obtaining a maximum relative error of the battery lifetime estimation between the model and the measurements of 21% for an assumed interarrival time (IAT) of 6 min.This work was supported in part by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund under Project TEC2016-76795-C6-4-R and in part by the H2020 European Project TRIANGLE under Grant 688712

A Survey on 5G Usage Scenarios and Traffic Models

The fifth-generation mobile initiative, 5G, is a tremendous and collective effort to specify, standardize, design, manufacture, and deploy the next cellular network generation. 5G networks will support demanding services such as enhanced Mobile Broadband, Ultra-Reliable and Low Latency Communications and massive Machine-Type Communications, which will require data rates of tens of Gbps, latencies of few milliseconds and connection densities of millions of devices per square kilometer. This survey presents the most significant use cases expected for 5G including their corresponding scenarios and traffic models. First, the paper analyzes the characteristics and requirements for 5G communications, considering aspects such as traffic volume, network deployments, and main performance targets. Secondly, emphasizing the definition of performance evaluation criteria for 5G technologies, the paper reviews related proposals from principal standards development organizations and industry alliances. Finally, well-defined and significant 5G use cases are provided. As a result, these guidelines will help and ease the performance evaluation of current and future 5G innovations, as well as the dimensioning of 5G future deployments.This work is partially funded by the Spanish Ministry of Economy and Competitiveness (project TEC2016-76795-C6-4-R)H2020 research and innovation project 5G-CLARITY (Grant No. 871428)Andalusian Knowledge Agency (project A-TIC-241-UGR18)

Asynchronous Time-Sensitive Networking for Industrial Networks

Time-Sensitive Networking (TSN) is expected to be a cornerstone in tomorrow’s industrial networks. That is because of its ability to provide deterministic quality-of-service in terms of delay, jitter, and scalability. Moreover, it enables more scalable, more affordable, and easier to manage and operate networks compared to current industrial networks, which are based on Industrial Ethernet. In this article, we evaluate the maximum capacity of the asynchronous TSN networks to accommodate industrial traffic flows. To that end, we formally formulate the flow allocation problem in the mentioned networks as a convex mixed-integer non-linear program. To the best of the authors’ knowledge, neither the maximum utilization of the asynchronous TSN networks nor the formulation of the flow allocation problem in those networks have been previously addressed in the literature. The results show that the network topology and the traffic matrix highly impact on the link utilization.This work has been partially funded by the H2020 research and innovation project 5G-CLARITY (Grant No. 871428), national research project TRUE5G: PID2019-108713RB-C5

5G Infrastructure Network Slicing: E2E Mean Delay Model and Effectiveness Assessment to Reduce Downtimes in Industry 4.0

This work has been partially funded by the H2020 project 5G-CLARITY (Grant No. 871428) and the Spanish national project TRUE-5G (PID2019-108713RB-C53).Fifth Generation (5G) is expected to meet stringent performance network requisites of the Industry 4.0. Moreover, its built-in network slicing capabilities allow for the support of the traffic heterogeneity in Industry 4.0 over the same physical network infrastructure. However, 5G network slicing capabilities might not be enough in terms of degree of isolation for many private 5G networks use cases, such as multi-tenancy in Industry 4.0. In this vein, infrastructure network slicing, which refers to the use of dedicated and well isolated resources for each network slice at every network domain, fits the necessities of those use cases. In this article, we evaluate the effectiveness of infrastructure slicing to provide isolation among production lines (PLs) in an industrial private 5G network. To that end, we develop a queuing theory-based model to estimate the end-to-end (E2E) mean packet delay of the infrastructure slices. Then, we use this model to compare the E2E mean delay for two configurations, i.e., dedicated infrastructure slices with segregated resources for each PL against the use of a single shared infrastructure slice to serve the performance-sensitive traffic from PLs. Also we evaluate the use of Time-Sensitive Networking (TSN) against bare Ethernet to provide layer 2 connectivity among the 5G system components. We use a complete and realistic setup based on experimental and simulation data of the scenario considered. Our results support the effectiveness of infrastructure slicing to provide isolation in performance among the different slices. Then, using dedicated slices with segregated resources for each PL might reduce the number of the production downtimes and associated costs as the malfunctioning of a PL will not affect the network performance perceived by the performance-sensitive traffic from other PLs. Last, our results show that, besides the improvement in performance, TSN technology truly provides full isolation in the transport network compared to standard Ethernet thanks to traffic prioritization, traffic regulation, and bandwidth reservation capabilities.H2020 project 5G-CLARITY 871428Spanish Government PID2019-108713RB-C53TRUE-5

Modeling and Dimensioning of a Virtualized MME for 5G Mobile Networks

Network function virtualization is considered one of the key technologies for developing future mobile networks. In this paper, we propose a theoretical framework to evaluate the performance of a Long-Term Evolution (LTE) virtualized mobility management entity (vMME) hosted in a data center. This theoretical framework consists of 1) a queuing network to model the vMME in a data center and 2) analytic expressions to estimate the overall mean system delay and the signaling workload to be processed by the vMME. We validate our mathematical model by simulation. One direct use of the proposed model is vMME dimensioning, i.e., to compute the number of vMME processing instances to provide a target system delay given the number of users in the system. Additionally, the paper includes a scalability analysis of the system. In our study, we consider the billing model and a data center setup of Amazon Elastic Compute Cloud service and estimate the processing time of MME processing instances for different LTE control procedures experimentally. For the considered setup, our results show that the vMME is scalable for signaling workloads up to 37 000 LTE control procedures per second for a target mean system delay of 1 ms. The system design and database performance assumed imposes this limit in the system scalability.This work was supported in part by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (project TIN2013-46223-P) and in part by the Spanish Ministry of Education, Culture, and Sport under FPU Grant 13/04833

Reduced M2M Signaling Communications in 3GPP LTE and Future 5G Cellular Networks

The increase of machine-to-machine (M2M) communications over cellular networks imposes new requirements and challenges that current networks have to handle with. Many M2M UEs (User Equipment) may send small infrequent data, which suppose a challenge for cellular networks not optimized for such traffic, where signaling load could increase significantly and cause congestion over the network. This paper evaluates current proposals to manage small transmissions over the Long Term Evolution (LTE) cellular network. We also propose a new Random Access-based Small IP packet Transmission (RASIPT) procedure for M2M UEs small data transmissions. Its main feature is data transfer without establishment of Radio Resource Control (RRC) connection to reduce signaling overhead. In our design, we assume a Software Defined Networking-based architecture for 5G system. When compared with current LTE scheme, our procedure reduces significantly the signaling load generated by M2M UEs small transmissions.This work is partially supported by the Spanish Ministry of Economy and Competitiveness (project TIN2013- 46223-P), FEDER and the Spanish Ministry of Education, Culture and Sport (FPU grant 13/04833)