Survey of Transportation of Adaptive Multimedia Streaming service in Internet

[DE] World Wide Web is the greatest boon towards the technological advancement of modern era. Using the benefits of Internet globally, anywhere and anytime, users can avail the benefits of accessing live and on demand video services. The streaming media systems such as YouTube, Netflix, and Apple Music are reining the multimedia world with frequent popularity among users. A key concern of quality perceived for video streaming applications over Internet is the Quality of Experience (QoE) that users go through. Due to changing network conditions, bit rate and initial delay and the multimedia file freezes or provide poor video quality to the end users, researchers across industry and academia are explored HTTP Adaptive Streaming (HAS), which split the video content into multiple segments and offer the clients at varying qualities. The video player at the client side plays a vital role in buffer management and choosing the appropriate bit rate for each such segment of video to be transmitted. A higher bit rate transmitted video pauses in between whereas, a lower bit rate video lacks in quality, requiring a tradeoff between them. The need of the hour was to adaptively varying the bit rate and video quality to match the transmission media conditions. Further, The main aim of this paper is to give an overview on the state of the art HAS techniques across multimedia and networking domains. A detailed survey was conducted to analyze challenges and solutions in adaptive streaming algorithms, QoE, network protocols, buffering and etc. It also focuses on various challenges on QoE influence factors in a fluctuating network condition, which are often ignored in present HAS methodologies. Furthermore, this survey will enable network and multimedia researchers a fair amount of understanding about the latest happenings of adaptive streaming and the necessary improvements that can be incorporated in future developments.Abdullah, MTA.; Lloret, J.; Canovas Solbes, A.; García-García, L. (2017). Survey of Transportation of Adaptive Multimedia Streaming service in Internet. Network Protocols and Algorithms. 9(1-2):85-125. doi:10.5296/npa.v9i1-2.12412S8512591-

Wireless Technologies for IoT in Smart Cities

[EN] As cities continue to grow, numerous initiatives for Smart Cities are being conducted. The concept of Smart City encompasses several concepts being governance, economy, management, infrastructure, technology and people. This means that a Smart City can have different communication needs. Wireless technologies such as WiFi, ZigBee, Bluetooth, WiMax, 4G or LTE (Long Term Evolution) have presented themselves as solutions to the communication needs of Smart City initiatives. However, as most of them employ unlicensed bands, interference and coexistence problems are increasing. In this paper, the wireless technologies available nowadays for IoT (Internet of Things) in Smart Cities are presented. Our contribution is a review of wireless technologies, their comparison and the problems that difficult coexistence among them. In order to do so, the characteristics and adequacy of wireless technologies to each domain are considered. The problems derived of over-crowded unlicensed spectrum and coexistence difficulties among each technology are discussed as well. Finally, power consumption concerns are addressed.García-García, L.; Jimenez, JM.; Abdullah, MTA.; Lloret, J. (2018). Wireless Technologies for IoT in Smart Cities. Network Protocols and Algorithms. 10(1):23-64. doi:10.5296/npa.v10i1.12798S236410

An architecture and protocol for smart continuous eHealth monitoring using 5G

[EN] Continuous monitoring of chronic patients improves their quality of life and reduces the economic costs of the sanitary system. However, in order to ensure a good monitoring, high bandwidth and low delay are needed. The 5G technology offers higher bandwidth, lower delays and packets loss than previous technologies. This paper presents an architecture for smart eHealth monitoring of chronic patients. The architecture elements include wearable devices, to collect measures from the body, and a smartphone at the patient side in order to process the data received from the wearable devices. We also need a DataBase with an intelligent system able to send an alarm when it detects that it is happening something anomalous. The intelligent system uses machine learning in BigData taken from different hospitals and the data received from the patient to diagnose and generate alarms. Experiment tests have been done to simulate the traffic from many users to the DataBase in order to evaluate the suitability of 5G in our architecture. When there are few users (less than 200 users), we do not find big differences of round trip time between 4G and 5G, but when there are more users, like 1000 users, it increases considerably reaching 4 times more in 4G The Packet Loss is almost null in 4G until 300 users, while in 5G it is possible to keep it null until 700 users. Our results point out that in order to have high number of patients continuously monitored, it is necessary to use the 5G network because it offers low delays and guarantees the availability of bandwidth for all users.This work has been partially supported by the "Ministerio de Educacion, Cultura y Deporte", through the "Ayudas para contratos predoctorales de Formacion del Profesorado Universitario FPU (Convocatoria 2014)". Grant number FPU14/02953.Lloret, J.; Parra-Boronat, L.; Abdullah, MTA.; Tomás Gironés, J. (2017). An architecture and protocol for smart continuous eHealth monitoring using 5G. Computer Networks. 129(2):340-351. https://doi.org/10.1016/j.comnet.2017.05.018S340351129

Interactive Videos in IPTV using Hypervideo Links

[EN] One of the main advantages of Internet Protocol Television (IPTV) is the capability of full duplex communication between the Television (TV) provider and the clients which permits the interactivity of both. From this interactivity, TV providers can obtain extra information from clients. Moreover, clients can even take profit from this type of communication that allows them surfing between videos. However, this feature cannot be used in Digital Terrestrial Television (DTT). This paper shows the design and development of an interactive video for IPTV services that contains hypervideo links with additional information and content that is very useful for viewers. Furthermore, we detail the protocol used to maintain the service between the TV provider and the clients to maintain the service. Finally, the system is tested in a real scenario and the resulting measurements are provided in order to evaluate the network performance needed to offer an adequate service to each client because according to results shows, the use of hypervideo links does not imply an important increase in the ratio of packets per second.This work has been partially supported by the Postdoctoral Scholarship Contratos Postdoctorales UPV 2014 (PAID-10-14) of the Universitat Politècnica de València , by the Programa para la Formación de Personal Investigador (FPI-2015-S2-884) of the Universitat Politècnica de València .Jimenez, JM.; Lloret, J.; Abdullah, MT.; Sendra, S. (2017). Interactive Videos in IPTV using Hypervideo Links. Network Protocols and Algorithms. 9(3-4):77-93. https://doi.org/10.5296/npa.v9i3-4.12540S779393-

Intelligent Algorithm for Enhancing MPEG-DASH QoE in eMBMS

[EN] Multimedia streaming is the most demanding and bandwidth hungry application in today¿s world of Internet. MPEG-DASH as a video technology standard is designed for delivering live or on-demand streams in Internet to deliver best quality content with the fewest dropouts and least possible buffering. Hybrid architecture of DASH and eMBMS has attracted a great attention from the telecommunication industry and multimedia services. It is deployed in response to the immense demand in multimedia traffic. However, handover and limited available resources of the system affected on dropping segments of the adaptive video streaming in eMBMS and it creates an adverse impact on Quality of Experience (QoE), which is creating trouble for service providers and network providers towards delivering the service. In this paper, we derive a case study in eMBMS to approach to provide test measures evaluating MPEG-DASH QoE, by defining the metrics are influenced on QoE in eMBMS such as bandwidth and packet loss then we observe the objective metrics like stalling (number, duration and place), buffer length and accumulative video time. Moreover, we build a smart algorithm to predict rate of segments are lost in multicast adaptive video streaming. The algorithm deploys an estimation decision regards how to recover the lost segments. According to the obtained results based on our proposal algorithm, rate of lost segments is highly decreased by comparing to the traditional approach of MPEG-DASH multicast and unicast for high number of users.This work has been partially supported by the Postdoctoral Scholarship Contratos Postdoctorales UPV 2014 (PAID-10-14) of the Universitat Politècnica de València , by the Programa para la Formación de Personal Investigador (FPI-2015-S2-884) of the Universitat Politècnica de València , by the Ministerio de Economía y Competitividad , through the Convocatoria 2014. Proyectos I+D - Programa Estatal de Investigación Científica y Técnica de Excelencia in the Subprograma Estatal de Generación de Conocimiento , project TIN2014-57991-C3-1-P and through the Convocatoria 2017 - Proyectos I+D+I - Programa Estatal de Investigación, Desarrollo e Innovación, convocatoria excelencia (Project TIN2017-84802-C2-1-P).Abdullah, MT.; Jimenez, JM.; Canovas Solbes, A.; Lloret, J. (2017). Intelligent Algorithm for Enhancing MPEG-DASH QoE in eMBMS. Network Protocols and Algorithms. 9(3-4):94-114. https://doi.org/10.5296/npa.v9i3-4.12573S9411493-

Smart Client-Server Protocol and Architecture for Adaptive Multimedia Streaming

En los últimos años, el consumo de servicios multimedia ha aumentado y se prevé que esta tendencia continúe en un futuro próximo, convirtiendo el tema de la evaluación de la Calidad de la Experiencia (QoE) en un tema muy importante para valorar el servicio de los proveedores. En este sentido, la optimización de la QoE recibe cada vez más atención ya que las soluciones actuales no han tenido en cuenta, la adaptación, la viabilidad, la rentabi-lidad y la fiabilidad. La presente memoria se centra en la caracterización, diseño, desarrollo y evaluación de diferentes aplicaciones multimedia, con el fin de optimizar la QoE. Por tanto, este trabajo investiga la influencia que la infraestructura de redes, las características de los videos y los terminales de los usuarios, presentan en la QoE de los servicios multimedia actuales en Internet. Esta tesis se basa en la investigación exhaustiva de la evaluación subjetiva y objetiva de QoE en redes heterogéneas. Los desafíos y cuestiones relacionados con el estado de la técnica y se discuten en esta disertación. En la primera fase, diseñamos una metodología de prueba para evaluar la QoE en la transmisión de video en directo y a través de plataformas de video bajo demanda en redes Wi-Fi y celulares. A partir de esta fase inicial, propondremos los problemas a investigar y las preguntas para resolver a lo largo de esta disertación. Nuestra metodología hace uso de métricas subjetivas y objetivas para evaluar la QoE percibida por los usuarios finales. Se realiza un conjunto de experimentos en laboratorio donde nuestra metodología de pruebas es aplicada. Los resultados obtenidos se recopilan y analizan para extraer las relaciones entre la Calidad de servicio (QoS) y QoE. A partir de estos resultados, se propone un mapeo de QoS-QoE que permite predecir la QoE. En la siguiente fase de la investigación, desarrollamos los algoritmos de optimización de QoE basados en la administración del sistema de red para redes Wi-Fi y celulares. Los algoritmos usan los parámetros clave que se tuvieron en cuenta para la evaluación de QoE. El objetivo de estos algorit-mos es proporcionar un sistema de gestión flexible para las redes con el ob-jetivo de lograr un equilibrio controlado entre la maximización de QoE y la eficiencia del uso de los recursos. Por último, se diseña el banco de pruebas del sistema para evaluar el rendimiento de las aplicaciones de servicios multimedia genéricos en los diferentes entornos de prueba. El banco de pruebas del sistema se basa en el enfoque de virtualización; usa los recursos compartidos de un hardware fí-sico para virtualizar todos los componentes. El banco de pruebas virtualiza-do proporciona funciones de red virtualizadas para diferentes escenarios, como Internet (las redes de distribución de contenido - CDNs) y redes inalámbricas. Por lo tanto, se adoptan protocolos livianos y mecanismos ágiles en el sistema, para proporcionar un mejor servicio a los usuarios fina-les. Los resultados de QoE son proporcionados a los proveedores de servi-cios de acuerdo con los parámetros que se definen en el proceso de la eva-luación. Como resultado hemos obtenido un sistema que presenta un servi-cio rentable como una forma factible para la evaluación de la prueba.In recent years, multimedia services consumption has increased and it is expected that this trend will continue in the near future, becoming the evaluation of Quality of Experience (QoE) as a very important issue for assessing the quality of providers' services. In this sense, the optimization of the QoE is progressively receiving much attention considering that current solutions are not based on the adaptation, feasibility, cost-effectiveness, and reliability. The present dissertation is focused on the characterization, design, development and evaluation of different multimedia applications aimed to optimize the QoE. Therefore, this work investigates the influence that the networks infrastructure, the videos' characteristics and the users' terminals present on QoE of the current Internet multimedia services. The work is based on a comprehensive research of subjective and objective assessments in heterogeneous networks. Challenges and research questions related to the state of the art are discussed in this dissertation. In the first phase of this dissertation, we design a test methodology for assessing QoE of live video streaming and video on demand platforms to be transmitted over Wi-Fi and cellular networks. From this initial step, we will propound the related research issues and questions to solve this dissertation. Our methodology considers the use of subjective and objective metrics to evaluate the QoE perceived by end-users. A set of laboratory experiments is conducted where our proposed methodology is applied. The obtained results are gathered and analyzed to extract the relations between Quality of Service (QoS) and QoE. From the results, we propose a QoS-QoE mapping which allows predicting QoE. In the next phase of the research, we develop QoE-optimization algorithms based on network system management for Wi-Fi and cellular networks. The algorithms use the key parameters that were taken into account for QoE assessment. The goal of these algorithms is to provide a flexible management system for the networks in order to achieve the desirable trade-off between QoE maximization and resource usage efficiency. Lastly, the system testbed is designed in order to evaluate the performance of generic multimedia services applications for the different environments under test. The system testbed is based on virtualization approach; it uses the shared resources of a physical hardware to virtualize all components. The virtualized testbed provides virtualized network functions for the different scenarios such as the Internet (Content Delivery Networks - CDNs) and wireless networks. Therefore, lightweight protocols and agile mechanisms are adopted in the system to provide enhanced service to end-users. The QoE results are reported to the service providers according to the parameters defined in the evaluation process. As a result, we have obtained a cost-effective system, which is considered as a feasible way for test evaluation.En els últims anys, el consum de serveis multimèdia ha augmentat i es preveu que aquesta tendència continue en un futur pròxim, convertitnt el tema de l'avaluació de la Qualitat d'Experiència (QoE) una tasca molt im-portant per a valorar el servei dels proveïdors. En aquest sentit, l'optimització de la QoE rep cada vegada més atenció degut a que les solucions actuals no tenen en compte, l'adaptació, la viabilitat, el rendiment i la fiabilitat. La present memòria se centra en la caracterització, disseny, desenvolupament i avaluació de diferents aplicacions multimèdia, amb la finalitat d'optimitzar la QoE. Per tant, aquest treball investiga la influència que la infraestructura de les xarxes, les característiques dels videos i els terminals dels usuaris tenen sobre la QoE dels serveis multimèdia actuals d'Iinternet. Aquesta tesi es basa en una recerca exhaustiva de l'avaluació subjectiva i objectiva de QoE en xarxes heterogènies. Els desafiaments i preguntes relacionats amb l'estat de la tècnica es discuteixen en aquesta dissertació. En la primera fase, dissenyem la metodologia de prova per a avaluar la QoE de transmissió de video en directe i de plataformes de video baix demanda en xarxes Wi-Fi i cel·lulars. A partir d'aquest primer pas, proposem els problemes de recerca relacionats i les preguntes a resoldre a través d'a-questa tesi. La nostra metodologia fa ús de mètriques subjectives i objecti-ves per a avaluar la QoE dels usuaris finals. Es realitzen un conjunt d'expe-riments en laboratori on s'aplica la nostra metodología. Els resultats obtin-guts es recopilen i analitzen per a extraure les relacions entre la QoS i la QoE. A partir d'aquests resultats, esproposa un mapatge de QoS-QoE que ens permetrà predir la QoE. En la següent fase de la recerca, desenvolupem els algoritmes d'optimi-tzació de la QoE per a l'administració de xarxes Wi-Fi i cel·lulars. Els algo-ritmes utilitzen els paràmetres clau que es van tenir en compte per a l'ava-luació de QoE. L'objectiu d'aquests algoritmes és proporcionar un sistema de gestió flexible per ales xarxes que permetrá aconseguir un equilibri con-trolat entre la maximització de la QoE i l'us eficient dels recursos. Finalment, el banc de proves del sistema està dissenyat per a avaluar el rendiment de les aplicacions de serveis multimèdia genèrics en els diferents entorns de prova. El banc de proves del sistema es basa en l'enfocament de virtualització; usa els recursos compartits d'un equip físic que virtualitza tots els components. El banc de proves virtualitzat proporciona les funcions de xarxa virtualitzades per a diferents escenaris, com Internet (les xarxes de distribució de continguts - CDNs) i xarxes sense fils. Per tant, s'adopten protocols lleugers i mecanismes àgils en el sistema per a proporcionar un millor servei als usuaris finals. Els resultats de QoE son proporcionats als proveïdors de serveis d'acord amb els paràmetres que es defineixen en el procés de l'avaluació. Com a resultat, hem obtés un sistema que presenta un servei rendible i com a viable per a l'avaluació de la prova.Abdullah, MT. (2018). Smart Client-Server Protocol and Architecture for Adaptive Multimedia Streaming [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/103324TESI

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research