Routing, Modulation and Spectrum Assignment Algorithm Using Multi-Path Routing and Best-Fit

Producción CientíficaElastic Optical Networks (EONs) are a promising optical technology to deal with the ever-increasing traffic and the vast number of connected devices of the next generation of the Internet, associated to paradigms like the Internet of Things (IoT), the Tactile Internet or the Industry 4.0, to name just a few. In this kind of optical network, each optical circuit or lightpath is provisioned by means of superchannels of variable bandwidth. In this manner, only the necessary bandwidth to accommodate the demand is allocated, improving the spectrum usage. When establishing a connection, the EON control layer determines the modulation format to be used and allocates a portion of the spectrum in a sequence of fibers from the source to the destination node providing the user-demanded bandwidth. This is known as the routing, modulation level and spectrum assignment (RMSA) problem. In this work, we firstly review the most important contributions in that area, and then, we propose a novel RMSA algorithm, multi-path best-fit (MP-BF), which uses a split spectrum multi-path strategy together with a spectrum assignment technique (best-fit), and which jointly exploit the flexibility of EONs. A simulation study has been conducted comparing the performance of EONs when using MP-BF with other proposals from the literature. The results of this study show that, by using MP-BF, the network can increase its performance in terms of lightpath request blocking ratio and supported traffic load, without affecting the energy per bit or the computation time required to find a solution

Hybrid RSS-RTT Localization Scheme for Indoor Wireless Networks

[EN]Nowadays, a variety of information related to the distance between two wireless devices can be easily obtained. This paper presents a hybrid localization scheme that combines received signal strength (RSS) and round-trip time (RTT) information with the aim of improving the previous localization schemes. The hybrid localization scheme is based on an RSS ranging technique that uses RTT ranging estimates as constraints among other heuristic constraints. Once distances have been well estimated, the position of the mobile station (MS) to be located is estimated using a new robust least-squared multilateration (RLSM) technique that combines the RSS and RTT ranging estimates mitigating the negative effect of outliers. The hybrid localization scheme coupled with simulations and measurements demonstrates that it outperforms the conventional RSS-based and RTT-based localization schemes, without using either a tracking technique or a previous calibration stage of the environment.Dirección General de Telecomunicaciones de la Consejería de Fomento de Castilla y Leó

International Conference on Broadband Communications, Networks and Systems

Producción CientíficaNetwork Function Virtualization (NFV) is considered to be one of the enabling technologies for 5G. NFV poses several challenges, like deciding the virtual network function (VNF) placement and chaining, and adding backup resources to guarantee the survivability of service chains. In this paper, we propose a genetic algorithm that jointly solves the VNF-placement, chaining and virtual topology design problem in WDM metro ring network, with the additional capacity of providing node protection. The simulation results show how important is to solve all of these subproblems jointly, as well as the benefits of using shared VNF and network resources between backup instances in order to reduce both the service blocking ratio and the number of active CPUs.Ministerio de Economía, Industria y Competitividad (grant TEC2017-84423-C3-1-P)Ministerio de Industria, Comercio y Turismo (grant BES 2015-074514)INTERREG V-A España-Portugal (POCTEP) (grant 0677_DISRUPTIVE_2_E)

A testbed and a simulation laboratory for training engineering students in optical access network technologies

Producción CientíficaEngineering profiles focused on next-generation optical networks are gaining immense importance due to new emerging services and the amount of data expected in future network scenarios. In fact, not only are optical access networks leading to a major revolution in the network industry, but passive optical networks are the most widely deployed access networks worldwide today. This should be a strong incentive for universities to train their students in these innovative and recent technologies. In this vein, we propose the deployment of an optical communication laboratory with on-site experimental sessions in which students work with commercial equipment and realistic working environments. These working environments are necessary to train professionals in the area of optical networks. However, due to the high cost of the optical communications equipment, it is not possible to have a working place for each group and we combine these experimental sessions with some simulation sessions to complete the training. We present the design of this lab and a qualitative and quantitative study aimed at analyzing students’ experiences, the skills they have acquired, and the potential impact on their future careers. This study shows that students have a very positive perception of the lab, emphasizing that working with real equipment helps them improve technical skills and assimilate theoretical knowledge. They also point out they would like a higher number of subjects in their degrees to employ this type of lab. Finally, students perceive these sessions as very useful for their professional future.Unión Europea a través del programa INTERREG V-A España-Portugal (project 0677_DISRUPTIVE_2_E)Junta de Castilla y León (grant VA085G19)Ministerio de Ciencia, Innovación y Universidades (grants TEC2017-84423-C3-1-P and RED2018-102585-T

2020 22nd International Conference on Transparent Optical Networks (ICTON)

Producción CientíficaNetwork Function Virtualization (NFV) is a promising networking paradigm that will ease the network manageability and increase its flexibility, while reducing costs. In this paradigm, operators must solve the Virtual Network Function (VNF) placement and chaining problems. It is also important to provide backup resources to ensure the survivability of the offered services when a node failure happens. In this paper, we compare two different protection approaches to ensure the service resilience: individual VNF protection and end-to-end protection. Results show the benefits in terms of use of computing resources and energy consumption of protecting each VNF individually, compared to the end-to-end protection approach.Ministerio de Economía, Industria y Competitividad (grant TEC2017-84423-C3-1-P)Ministerio de Industria, Comercio y Turismo (fellowship BES-2015-074514)Research network Go2Edge (grant RED2018-102585-T)Interreg V-A Spain-Portugal (POCTEP) programme 2014- 202

A Framework for Next Generation Cloud-Native SDN Cognitive Resource Orchestrator for IoTs (NG2CRO)

Producción CientíficaSDN (Software Define Networking) and NFV (Network Function Virtualization) are the key enablers for 5G systems and also open many doors in the cloud-native application. Besides, it invites new challenges to the efficiency and scalability of resource management. This work aims to provide a cognitive framework for 5G resource and service orchestration in a cloud-native SDN environment. The proposed NG2CRO framework resource orchestrator is designed to adapt the network’s self-learning capabilities and dynamicity while taken on to account the network’s Markovian properties and diverse service requirements. We consider incorporating AI (Artificial Intelligence) techniques specifically RL (Reinforcement Learning) methodologies because literature has shown that these techniques can efficiently address and comply with the current dynamic behaviors and heterogeneity of 5G services and applications. In conclusion, both benefits and liabilities are discussed of incorporating AI specifically RL into resource orchestration practices that provide us with future research challenges.EU H2020 MSCA ITN-ETN IoTalentum (grant no. 953442)Consejería de Educación de la Junta de Castilla y León y FEDER (VA231P20)Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación (Proyecto PID2020-112675RB-C42 financiado por MCIN/AEI/10.13039/501100011033

2021 International Conference on Optical Network Design and Modeling (ONDM)

Producción CientíficaThe planning of multi-access edge computing (MEC) systems does not only consist in distributing MEC servers among the base stations (BSs) but also in designing the network to interconnect BSs, MEC resources and the wide area network (WAN) gateway. Due to their high bandwidth, fiber links are the best option for those connections in 5G environments. In contrast to previous works, which only solve the server placement problem, in this paper, an integer linear programming (ILP) formulation is proposed for solving both problems while reducing the installation cost (servers and fibers). The fiber deployment cost is especially important in sparsely populated areas as the distance between BSs are much longer than in urban environments. The model was tested using real BSs locations and population data showing that the formulation considerably reduces the installation cost.Interreg V-A Spain-Portugal (POCTEP) programme 2014- 2020 (project 0667_DISRUPTIVE_2_E)Ministerio de Economía, Industria y Competitividad (projects TEC2017-84423-C3-1-P and RED2018- 102585-T)Junta de Castilla y León - Fondo Europeo de Desarrollo Regional (project VA231P20

FITCE 2017

Producción CientíficaThe following topics are dealt with: protocols; telecommunication computing; cloud computing; mean square error methods; 5G mobile communication; optical fibre subscriber loops; optical fibre networks; passive optical networks; optical time-domain reflectometry; computer aided instruction.Ministerio de Ciencia e Innovación (Projects TEC2014-53071-C3-2-P and TEC2015-71932-REDT

2022 IEEE International Mediterranean Conference on Communications and Networking (MeditCom)

Producción CientíficaIn Multi-access Edge Computing (MEC) network planning, the main goal is to find the optimal network topology, including the location and dimensioning of MEC data centers (MEC-DC), and the connections between them, with base stations (BSs), and with the wide area network (WAN) gateway for Internet and cloud services. Moreover, the assignment of traffic to the servers must also be solved. When solving that problem, it is especially important to consider the connections if the deployment has to be done in sparsely populated areas with long distances to interconnect and where it is likely to find no adequate infrastructure previously deployed. In a previous paper, we presented an Integer Linear Programming (ILP) formulation that solves that problem assuming straight and dedicated cable ducts between network nodes. However, reusing cables ducts and exploiting space division multiplexing (using different fibers of each cable to reach different nodes) can lead to more cost-effective solutions. Moreover, it is crucial to implement redundancy between MEC-DCs and WAN gateways to provide survivability against failures in this network segment. In this paper, we present a heuristic to improve the result obtained with our previous ILP formulation, assuming shared fiber ducts and cables, and creating a ring topology between MEC-DCs and WAN gateways. Results show that our proposal reduces the total deployment cost, while fulfilling latency constraints of MEC applications and providing fault tolerance.FEDER a través del Programa INTERREG V-A España-Portugal 2014-2020 (0677_DISRUPTIVE_2_E)Consejería de Educación de la Junta de Castilla y León y FEDER (VA231P20)Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación (Proyecto PID2020-112675RB-C42 financiado por MCIN/AEI/10.13039/501100011033 y RED2018-102585-T

2022 32nd International Telecommunication Networks and Applications Conference (ITNAC)

Producción CientíficaThe upcoming Connected and cooperative and automated mobility paradigm (CCAM) requires the deployment of road-side units (RSUs) beside the roads to provide wireless communication to connected-vehicle on board units. The deployment of RSUs along the highways provide low-latency communication, suitable for applications where high-speed response is needed, such as autonomous driving and crash avoidance. These RSUs must be connected to the Internet through a high-bandwidth and reliable access network being the optical fiber technologies the most convenient technology for that. In this paper, we propose a planning scheme for enabling RSUs with optical access networks. The method starts choosing the locations of the access network headers (the connection points to the local service provider facilities), and then defines the connections between the headers and the RSUs in a convenient manner considering the road infrastructure. Then, two deployment technologies based on optical fibers are compared: Point to Point (P2P) and Passive Optical Network (PON). A techno-economic analysis was performed, and results show that P2P and PON approaches are very similar in terms of cost, therefore, due to technical advantages, P2P is recommended as deployment strategy for the described scenario.Consejería de Educación de la Junta de Castilla y León y FEDER (VA231P20)Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación (Proyecto PID2020-112675RB-C42 financiado por MCIN/AEI/10.13039/501100011033 y RED2018-102585-T)FEDER a través del Programa INTERREG V-A España-Portugal 2014-2020 (0677_DISRUPTIVE_2_E