Inter-Datacenter Connectivity in Flexgrid-based Optical Networks

The huge energy consumption of datacenters (DC) requires an elastic resource management, e.g. by turning servers off when they are not used or turning them on to satisfy increments in the demand. Thanks to virtualization, jobs (e.g., web applications) can be encapsulated in virtual machines (VM) mixed with other workloads and consolidate them in the most proper server according to their performance goals. Local resource managers in DCs can migrate VMs from one server to another looking for reducing energy consumption while ensuring the committed quality of experience (QoE). Additionally, cloud providers can create DC federations based on a geographically distributed infrastructure so they can manage appropriately green energy resources available in each DC, thus reducing energy expenditure. Scheduling algorithms can perform VM migration not only within a single DC but also transferring a huge amount of raw data from one DC to another to minimize operational costs while ensuring the QoE. Since traffic between DCs is generated by VM migration, the connectivity required between two DCs highly varies along the day, presenting dramatic differences in an hourly time scale. Therefore, using a flexgrid-based optical network to interconnect DCs is an option to be considered since that technology provides fine and multiple granularity. In flexgrid optical networks the available optical spectrum is divided into frequency slices of fixed spectrum width. Optical connections can be allocated into a variable number of these slices, and its capacity can be dynamically managed by allocating or releasing slices provided that the spectrum allocated to an optical connection remain contiguous. Network providers can facilitate the interconnection among federated DCs by allowing them to request connections’ set up on demand with the desired bitrate, while tearing down those connections when they are not needed. With this aim, in the last years, huge standardization work has been done defining control plane architectures and protocols to automate connection provisioning. The Internet Engineering Task Force (IETF) is defining the Application-Based Network Operations (ABNO) architecture, which is based on standard components such as the active stateful Path Computation Element (PCE). This thesis is devoted to characterize, evaluate and analyze the problem providing optimal VM placement so as to minimize operational costs assuming that those costs are dominated by energy and communication costs. To this aim, analytical models to optimize energy consumption in DC federations are provided. Both cloud and core optical network control architectures are explored and new connectivity models for elastic operations are proposed. Mixed integer linear programming models as well as heuristic algorithms are developed and simulations are carried out. More specifically, the main objective has been attained by developing three goals covering different open issues. First we propose the Elastic Operations in Federated Datacenters for Performance and Cost Optimization (ELFADO) problem for scheduling workload and orchestrating federated DCs. A distributed and a centralized approach are studied. Second we propose architectures based on ABNO, using cross-stratum orchestration and carrier SDN, as well as elastic connectivity models supported: the dynamic elastic model and a transfer mode model respectively. Finally, we consider the centralized ELFADO and both the dynamic elastic and transfer mode connectivity models proposed and evaluate their performance

Vulnerabilidad de los puertos españoles ante el cambio climático. Vol. 1: Tendencias de variables físicas oceánicas y atmosféricas durante las últimas décadas y proyecciones para el siglo XXI

La presente publicación, el primer volumen de dos libros previstos sobre el tema, se centra en describir los resultados de los trabajos que se han realizado desde Puertos del Estado, el IMEDEA y AEMET para la caracterización de la evolución de las variables climáticas a lo largo del Siglo XXI. Los datos expuestos son el resultado de un enorme esfuerzo de computación numérica establecido a lo largo de 7 años en una serie de proyectos de investigación financiados por el Ministerio de Economía y Competitividad y por el Ministerio de Medio Ambiente, y su generación ha sido también posible gracias a la colaboración con multitud de centros internacionales de referencia, como MeteoFrance y Mercatorocean en Francia, o el National Oceanography Centre, en Reino Unido. Estos trabajos se enmarcan, además, en la estrategia española sobre cambio climático, y están coordinados con las actividades de la Oficina Española de Cambio Climático

Innocampus Explora: una aproximación multidisciplinar a la problemática ambiental

[ES] Presentamos las actividades del proyecto de innovación Innocampus Explora desarrollado en el campus de Burjassot-Paterna de la Universitat de València y cuyo objetivo principal es mostrar la interrelación existente entre los diferentes grados científicos y técnicos del campus. En la presente anualidad, el equipo de trabajo integrado por estudiantes y profesores de todos las facultades y escuelas del campus de Burjassot-Paterna, ha desarrollado actividades en torno a la problemática medioambiental. Una visión transversal e interdisciplinar de los problemas de los usos del plástico y de la energía nuclear que enlaza con varios de los Objetivos de Desarrollo Sostenible (ODS) dictados por Naciones Unidas. Con el desarrollo de este proyecto contribuimos a una formación transversal de calidad para todos los estudiantes participantes.[EN] We present the activities of the Innocampus Explora innovation project developed on the Burjassot-Paterna campus of the Universitat de València and whose main objective is to show the interrelation between the different scientific and technical degrees on campus. In this year, the work team made up of students and professors from all the faculties and schools of the Burjassot-Paterna campus, have carried out activities around environmental issues. A cross-sectional and interdisciplinary vision of the problems of the uses of plastic and nuclear energy that link with several of the Sustainable Development Goals (SDGs) dictated by the United Nations. With the development of this project we contribute to quality transversal training for all participating students.Moros Gregorio, J.; Quílez Asensio, A.; Jimenez Romero, D.; Blas Medina, A.; Giménez Escamilla, I.; Amorós Hernández, L.; Giner, L.... (2021). Innocampus Explora: una aproximación multidisciplinar a la problemática ambiental. En IN-RED 2020: VI Congreso de Innovación Educativa y Docencia en Red. Editorial Universitat Politècnica de València. 1003-1014. https://doi.org/10.4995/INRED2020.2020.11996OCS1003101

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

Inter-Datacenter Connectivity in Flexgrid-based Optical Networks

The huge energy consumption of datacenters (DC) requires an elastic resource management, e.g. by turning servers off when they are not used or turning them on to satisfy increments in the demand. Thanks to virtualization, jobs (e.g., web applications) can be encapsulated in virtual machines (VM) mixed with other workloads and consolidate them in the most proper server according to their performance goals. Local resource managers in DCs can migrate VMs from one server to another looking for reducing energy consumption while ensuring the committed quality of experience (QoE). Additionally, cloud providers can create DC federations based on a geographically distributed infrastructure so they can manage appropriately green energy resources available in each DC, thus reducing energy expenditure. Scheduling algorithms can perform VM migration not only within a single DC but also transferring a huge amount of raw data from one DC to another to minimize operational costs while ensuring the QoE. Since traffic between DCs is generated by VM migration, the connectivity required between two DCs highly varies along the day, presenting dramatic differences in an hourly time scale. Therefore, using a flexgrid-based optical network to interconnect DCs is an option to be considered since that technology provides fine and multiple granularity. In flexgrid optical networks the available optical spectrum is divided into frequency slices of fixed spectrum width. Optical connections can be allocated into a variable number of these slices, and its capacity can be dynamically managed by allocating or releasing slices provided that the spectrum allocated to an optical connection remain contiguous. Network providers can facilitate the interconnection among federated DCs by allowing them to request connections’ set up on demand with the desired bitrate, while tearing down those connections when they are not needed. With this aim, in the last years, huge standardization work has been done defining control plane architectures and protocols to automate connection provisioning. The Internet Engineering Task Force (IETF) is defining the Application-Based Network Operations (ABNO) architecture, which is based on standard components such as the active stateful Path Computation Element (PCE). This thesis is devoted to characterize, evaluate and analyze the problem providing optimal VM placement so as to minimize operational costs assuming that those costs are dominated by energy and communication costs. To this aim, analytical models to optimize energy consumption in DC federations are provided. Both cloud and core optical network control architectures are explored and new connectivity models for elastic operations are proposed. Mixed integer linear programming models as well as heuristic algorithms are developed and simulations are carried out. More specifically, the main objective has been attained by developing three goals covering different open issues. First we propose the Elastic Operations in Federated Datacenters for Performance and Cost Optimization (ELFADO) problem for scheduling workload and orchestrating federated DCs. A distributed and a centralized approach are studied. Second we propose architectures based on ABNO, using cross-stratum orchestration and carrier SDN, as well as elastic connectivity models supported: the dynamic elastic model and a transfer mode model respectively. Finally, we consider the centralized ELFADO and both the dynamic elastic and transfer mode connectivity models proposed and evaluate their performance

Dynamic virtual network connectivity services to support C-RAN backhauling

Aiming at satisfying in a cost-effective manner the forecast traffic growth that future mobile networks will need to support, traditional distributed Radio Access Networks (RANs) are evolving towards centralized architectures. Specifically, the Cloud-RAN (C-RAN) architecture has shown that can alleviate to some extent the ever increasing Total Cost of Ownership in mobile networks. The current trend in C-RAN is to separate Remote Radio Heads (RRH) with radio frequency (RF) functions and Baseband Units (BBU) gathering baseband processing. This functional split allows keeping RF modules close to the antennas while placing BBUs at centralized locations so they can be shared among different sites and even be virtualized. However, some issues still need to be addressed in future mobile networks, especially due to the dynamicity of services and the strict constraints imposed by the interfaces needed. In fact, connectivity reconfiguration for X2 and S1 backhaul interfaces needs to be provided as an all-or-nothing request to enable mobile resources reconfiguration in a geographical area. In view of that, in this paper we propose dynamic Customer Virtual Network (CVN) reconfiguration to be supported in metro and core network segments. Such CVN requests must include Quality of Service constraints to ensure specific delay constraints, as well as bit rate guarantees to avoid service interruption. A mathematical formulation and a heuristic algorithm are presented for the CVN reconfiguration problem and exhaustive simulation results study its performance on realistic scenarios.Peer ReviewedPostprint (author's final draft

Requirements to support cloud, video and 5G services on the telecom cloud

The growth of data traffic related to datacenter (DC) interconnection and the expected explosion of services requiring intensive use of telecom networks, such as video and mobile services, are contributing to the increment of the traffic that transport networks need to support. In fact, Cisco has recently forecast that in the next few years IP traffic related to video services will correspond up to the 80% of the total IP traffic and that mobile data traffic will reach about 367 EB per month by 2020. Aiming at reducing Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) required to satisfy demand growth, service providers are exploring new approaches in contrast to traditional ones. From the transport network perspective, aiming at supporting such traffic growth, telecom network operators need to satisfy services requirements without incurring in network performance degradation and in a cost-effective manner. Therefore, cloud-ready transport networks are on the scope of different network providers, including intelligent control architectures and elastic data planes; i.e. based on novel optical technologies. Considering the telecom cloud, where telecom network resources can be offered as a service, in this paper we present three use cases related to DC interconnection, video distribution and 5G networks, and identify their basic connectivity needs from the transport networks according to realistic scenarios. © 2016 IEEE.Peer ReviewedPostprint (published version

Connectivity requirements for cloud-based services

The expected explosion of services offered in the cloud has revealed new paradigms in telecommunication networks and motivated research to satisfy the needs arising. Interconnection between facilities hosting computing resources or between computing resources and end-users may require service-specific Service Level Agreement (SLA) parameters. In this paper, we study the minimum connectivity requirements that transport networks need to satisfy to support cloud services and we map relevant Key Performance Indicators (KPIs) to them. Three clearly differentiated cloud-based scenarios are studied: datacenter (DC) interconnection in DC federations, live-TV distribution, and Cloud-Radio Access Networks (C-RAN) to support next generation mobile networks.Peer ReviewedPostprint (published version

Connectivity requirements for cloud-based services

The expected explosion of services offered in the cloud has revealed new paradigms in telecommunication networks and motivated research to satisfy the needs arising. Interconnection between facilities hosting computing resources or between computing resources and end-users may require service-specific Service Level Agreement (SLA) parameters. In this paper, we study the minimum connectivity requirements that transport networks need to satisfy to support cloud services and we map relevant Key Performance Indicators (KPIs) to them. Three clearly differentiated cloud-based scenarios are studied: datacenter (DC) interconnection in DC federations, live-TV distribution, and Cloud-Radio Access Networks (C-RAN) to support next generation mobile networks.Peer Reviewe

Requirements to support cloud, video and 5G services on the telecom cloud

The growth of data traffic related to datacenter (DC) interconnection and the expected explosion of services requiring intensive use of telecom networks, such as video and mobile services, are contributing to the increment of the traffic that transport networks need to support. In fact, Cisco has recently forecast that in the next few years IP traffic related to video services will correspond up to the 80% of the total IP traffic and that mobile data traffic will reach about 367 EB per month by 2020. Aiming at reducing Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) required to satisfy demand growth, service providers are exploring new approaches in contrast to traditional ones. From the transport network perspective, aiming at supporting such traffic growth, telecom network operators need to satisfy services requirements without incurring in network performance degradation and in a cost-effective manner. Therefore, cloud-ready transport networks are on the scope of different network providers, including intelligent control architectures and elastic data planes; i.e. based on novel optical technologies. Considering the telecom cloud, where telecom network resources can be offered as a service, in this paper we present three use cases related to DC interconnection, video distribution and 5G networks, and identify their basic connectivity needs from the transport networks according to realistic scenarios. © 2016 IEEE.Peer Reviewe