Resource Management in E-health Systems

E-health systems are the information and communication systems deployed to improve quality and efficiency of public health services. Within E-health systems, wearable sensors are deployed to monitor physiology information not only in hospitals, but also in our daily lives under all types of activities; wireless body area networks (WBANs) are adopted to transmit physiology information to smartphones; and cloud servers are utilized for timely diagnose and disease treatment. The integrated services provided by E-health systems could be more convenient, reliable, patient centric and bring more economic healthcare services. Despite of many benefits, e-health systems face challenges among which resource management is the most important one as wearable sensors are energy and computing capability limited, and medical information has stringent quality of service (QoS) requirements in terms of delay and reliability. This thesis presents resource management mechanisms, including transmission power allocation schemes for wearable sensors, Medium Access Control (MAC) for WBANs, and resource sharing schemes among cloud networks, that can efficiently exploit the limited resources to achieve satisfactory QoS. First, we address how wearable sensors could energy efficiently transmit medical information with stringent QoS requirements to a smart phone. We first investigate how to provide worst-case delay provisioning for vital physiology information. Sleep scheduling and opportunistic channel access are exploited to reduce energy consumption in idle listening and increase energy efficiency. Considering dynamic programming suffers from curse of dimensionality, Lyapunov optimization formulation is established to derive a low complexity two-step transmission power allocation algorithm. We analyze the conditions under which the proposed algorithm could guarantee worst-case delay. We then investigate the impacts of peak power constraint and statistical QoS provisioning. An optimal transmission power allocation scheme under a peak power constraint is derived, and followed by an efficient calculation method. Applying duality gap analysis, we characterize the upper bound of the extra average transmission power incurred due a peak power constraint. We demonstrate that when the peak power constraint is stringent, the proposed constant power scheme is suitable for wearable sensors for its performance is close to optimal. Further, we show that the peak power constraint is the bottleneck for wearable sensors to provide stringent statistical QoS provisioning. Second, WBANs can provide low-cost and timely healthcare services and are expected to be widely adopted in hospitals. We develop a centralized MAC layer resource management scheme for WBANs, with a focus on inter-WBAN interference mitigation and sensor power consumption reduction. Based on the channel state and buffer state information reported by smart phones deployed in each WBAN, channel access allocation is performed by a central controller to maximize the network throughput. Note that sensors have insufficient energy and computing capability to timely provide all the necessary information for channel resource management, which deteriorates the network performance. We exploit the temporal correlation of body area channel such that channel state reports from sensors are minimized. We then formulate the MAC design problem as a partially observable optimization problem and develop a myopic policy accordingly. Third, cloud computing is expected to meet the rising computing demands. Both private clouds, which aim at patients in their regions, and public clouds, which serve general public, are adopted. Reliability control and QoS provisioning are the core issues of private clouds and public clouds, respectively. A framework, which exploits the abundant resource of private clouds in time domain, to enable cooperation among private clouds and public clouds, is proposed. Considering the cost of service failure in e-health system, the first time failure probability is adopted as reliability measures for private clouds. An algorithm is proposed to minimize the failure probability, and is proven to be optimal. Then, we propose an e-health monitoring system with minimum service delay and privacy preservation by exploiting geo-distributed clouds. In the system, the resource management scheme enables the distributed cloud servers to cooperatively assign the servers to the requested users under a load balance condition. Thus, the service delay for users is minimized. In addition, a traffic shaping algorithm is proposed, which converts the user health data traffic to the non-health data traffic such that the capability of traffic analysis attacks is largely reduced. In summary, we believe the research results developed in this dissertation can provide insights for efficient transmission power allocation for wearable sensor, can offer practical MAC layer solutions for WBANs in hospital environment, and can improve the QoS provisioning provided by cloud networks in e-health systems

QoS-Aware energy management in body sensor nodes powered by human energy harvesting

Harvesting energy in the human environment has been identified as an effective way to charge the body sensor nodes in wireless body area networks (WBANs). In such networks, the capability of the nodes to detect events is of vital importance and complements the stringent quality of service (QoS) demands in terms of delay, throughput, and packet loss. However, the scarce energy collected by human motions, along with the strict requirements of vital health signals in terms of QoS, raises important challenges for WBANs and stresses the need for new integrated QoS-aware energy management schemes. In this paper, we propose a joint power-QoS (PEH-QoS) control scheme, composed of three modules that interact in order to make optimal use of energy and achieve the best possible QoS. The proposed scheme ensures that a sensor node is able to detect the medical events and transmit the respective data packets efficiently. Extensive simulations, conducted for different human activities (i.e., relaxing, walking, running, and cycling), have shown that the application of PEH-QoS in a medical node increases the detection efficiency, the throughput, and the energy efficiency of the system.Peer ReviewedPostprint (author's final draft

Resource Allocation in Wireless Body Area Networks: A Smart City Perspective

Healthcare is an essential service in smart cities. To deploy healthcare systems in such cities, personal health monitoring systems, infrastructure for collecting and delivering individual data, and a system for diagnosing symptoms are required. For the first requirement, wireless body area networks (WBANs) have recently received considerable attention from research communities. Owing to their main distinguishable features from general wireless sensor networks, research challenges regarding WBANs have been focused on network topology around the body and implanted nodes, efficient resource allocation, and power control. In this chapter, we provide a comprehensive discussion on the emerging research trends in the area of wireless sensor networks and a discussion of WBANs in terms of their resource allocation

Reliable, Context-Aware and Energy-Efficient Architecture for Wireless Body Area Networks in Sports Applications

RÉSUMÉ Un Réseau Corporel Sans Fil (RCSF, Wireless Body Area Network en anglais ou WBAN) permet de collecter de l'information à partir de capteurs corporels. Cette information est envoyée à un hub qui la transforme et qui peut aussi effectuer d'autres fonctions comme gérer des événements corporels, fusionner les données à partir des capteurs, percevoir d’autres paramètres, exécuter les fonctions d’une interface d’utilisateur, et faire un lien vers des infrastructures de plus haut niveau et d’autres parties prenantes. La réduction de la consommation d'énergie d’un RCSF est un des aspects les plus importants qui doit être amélioré lors de sa conception. Cet aspect peut impliquer le développement de protocoles de Contrôles d'Accès au Support (CAS, Media Access Control en anglais ou MAC), protocoles de transport et de routage plus efficients. Le contrôle de la congestion est un autre des facteurs les plus importants dans la conception d’un RCSF, parce que la congestion influe directement sur la Qualité De Service (QDS, Quality of Service en anglais ou QoS) et l’efficience en énergie du réseau. La congestion dans un RCSF peut produire une grande perte de paquets et une haute consommation d’énergie. La QDS est directement impactée par la perte de paquets. L’implémentation de mesures additionnelles est nécessaire pour atténuer l’impact sur la communication des RCSF. Les protocoles de CAS pour RCSF devraient permettre aux capteurs corporels d’accéder rapidement au canal de communication et d’envoyer les données au hub, surtout pour les événements urgents tout en réduisant la consommation d’énergie. Les protocoles de transport pour RCSF doivent fournir de la fiabilité bout-à-bout et de la QDS pour tout le réseau. Cette tâche peut être accomplie par la réduction du ratio de perte de paquets (Packet Loss Ratio en anglais ou PLR) et de la latence tout en gardant l'équité et la faible consommation d'énergie entre les noeuds. Le standard IEEE 802.15.6 suggère un protocole de CAS qui est destiné à être applicable à tous les types de RCSF; toutefois, ce protocole peut être amélioré pour les RCSF utilisés dans le domaine du sport, où la gestion du trafic pourrait être différente d’autres réseaux. Le standard IEEE 802.15.6 comprend la QDS, mais cela ne suggère aucun protocole de transport ou système de contrôle du débit. Le but principal de ce projet de recherche est de concevoir une architecture pour RCSF en trois phases : (i) Conception d’un mécanisme sensible au contexte et efficient en énergie pour fournir une QDS aux RCSF; (ii) Conception d’un mécanisme fiable et efficient en énergie pour fournir une récupération des paquets perdus et de l’équité dans les RCSF; et (iii) Conception d’un système de contrôle du débit sensible au contexte pour fournir un contrôle de congestion aux RCSF. Finalement, ce projet de recherche propose une architecture fiable, sensible au contexte et efficiente en énergie pour RCSF utilisés dans le domaine du sport. Cette architecture fait face à quatre défis : l'efficacité de l'énergie, la sensibilité au contexte, la qualité de service et la fiabilité. La mise en place de cette solution aidera à l’amélioration des compétences, de la performance, de l’endurance et des protocoles d’entraînement des athlètes, ainsi qu’à la détection des points faibles. Cette solution pourrait être prolongée à l’amélioration de la qualité de vie des enfants, des personnes malades ou âgées, ou encore aux domaines militaires, de la sécurité et du divertissement. L’évaluation des protocoles et schémas proposés a été faite par simulations programmées avec le simulateur OMNeT++ et le système Castalia. Premièrement, le protocole de CAS proposé a été comparé avec les protocoles de CAS suivants : IEEE 802.15.6, IEEE 802.15.4 et T-MAC (Timeout MAC). Deuxièmement, le protocole de CAS proposé a été comparé avec le standard IEEE 802.15.6 avec et sans l’utilisation du protocole de transport proposé. Finalement, le protocole de CAS proposé et le standard IEEE 802.15.6 ont été comparés avec et sans l’utilisation du système de contrôle du débit proposé. Le protocole de CAS proposé surpasse les protocoles de CAS IEEE 802.15.6, IEEE 802.15.4 et T-MAC dans le pourcentage de pertes de paquets d’urgence et normaux, l’efficacité en énergie, et la latence du trafic d’urgence et du trafic normal. Le protocole de CAS proposé utilisé avec le protocole du transport proposé surpasse la performance du standard IEEE 802.15.6 dans le pourcentage de perte de paquets avec ou sans trafic d’urgence, l’efficacité en énergie, et la latence du trafic normal. Le système de contrôle du débit proposé a amélioré la performance du protocole de CAS proposé et du standard IEEE 802.15.6 dans le pourcentage de perte de paquets avec ou sans trafic d’urgence, l’efficacité en énergie, et la latence du trafic d’urgence.----------ABSTRACT Information collected from body sensors in a Wireless Body Area Network (WBAN) is sent to a hub or coordinator which processes the information and can also perform other functions such as managing body events, merging data from sensors, sensing other parameters, performing the functions of a user interface and bridging the WBAN to higher-level infrastructure and other stakeholders. The reduction of the power consumption of a WBAN is one of the most important aspects to be improved when designing a WBAN. This challenge might imply the development of more efficient Medium Access Control (MAC), transport and routing protocols. Congestion control is another of the most important factors when a WBAN is designed, due to its direct impact in the Quality of Service (QoS) and the energy efficiency of the network. The presence of congestion in a WBAN can produce a big packet loss and high energy consumption. The QoS is also impacted directly by the packet loss. The implementation of additional measures is necessary to mitigate the impact on WBAN communications. The MAC protocols for WBANs should allow body sensors to get quick access to the channel and send data to the hub, especially in emergency events while reducing the power consumption. The transport protocols for WBANs must provide end-to-end reliability and QoS for the whole network. This task can be accomplished through the reduction of both the Packet Loss Ratio (PLR) and the latency while keeping fairness and low power consumption between nodes. The IEEE 802.15.6 standard suggests a MAC protocol which is intended to be applicable for all kinds of WBANs. Nonetheless, it could be improved for sports WBANs where the traffic-types handling could be different from other networks. The IEEE 802.15.6 standard supports QoS, but it does not suggest any transport protocol or rate control scheme. The main objective of this research project is to design an architecture for WBANs in three phases: (i) Designing a context-aware and energy-efficient mechanism for providing QoS in WBANs; (ii) Designing a reliable and energy-efficient mechanism to provide packet loss recovery and fairness in WBANs; and (iii) Designing a context-aware rate control scheme to provide congestion control in WBANs. Finally, this research project proposes a reliable, context-aware and energy-efficient architecture for WBANs used in sports applications, facing four challenges: energy efficiency, context awareness, quality of service and reliability. The benefits of this solution will help to improve skills, performance, endurance and training protocols of athletes, and deficiency detection. Also, it could be extended to enhance the quality of life of children, ill and elderly people, and to security, military and entertainment fields. The evaluation of the proposed protocols and schemes was made through simulations programed in the OMNeT++ simulator and the Castalia framework. First, the proposed MAC protocol was compared against the IEEE 802.15.6 MAC protocol, the IEEE 802.15.4 MAC protocol and the T-MAC (Timeout MAC) protocol. Second, the proposed MAC protocol was compared with the IEEE 802.15.6 standard with and without the use of the proposed transport protocol. Finally, both the proposed MAC protocol and the IEEE 802.15.6 standard were compared with and without the use of the proposed rate control scheme. The proposed MAC protocol outperforms the IEEE 802.15.6 MAC protocol, the IEEE 802.15.4 MAC protocol and the T-MAC protocol in the percentage of emergency and normal packet loss, the energy effectiveness, and the latency of emergency and normal traffic. The proposed MAC protocol working along with the proposed transport protocol outperforms the IEEE 802.15.6 standard in the percentage of the packet loss with or without emergency traffic, the energy effectiveness, and the latency of normal traffic. The proposed rate control scheme improved the performance of both the proposed MAC protocol and the IEEE 802.15.6 standard in the percentage of the packet loss with or without emergency traffic, the energy effectiveness and the latency of emergency traffic

A Review on Critical Data Transmission in Wireless Body Area Networks

Wireless body area networks (WBANs) assemble multiple transceiver nodes in, on, or around a patient's body to transmit physiological signals to the sink node and further send it to the medical personnel via a medical server. WBANs a sensor network that is characterized as energy-dependent. Due to this finite nature, the deployment of intelligent utilization is needed. Quality of service (QoS) is another area that needs rapt attention to receive exactly what was sent from the source node to the destination node and throughput. Critical data transmission is characterized by abnormal data status that requires an urgent response from the medical personnel without delay to save the patient's life. In this review article, we propose a review of critical data transmission in wireless body area networks. However, most past articles in this line focus more on energy-efficient, security and privacy, quality of the links, throughput, network maximization, and so on. None of them looks into the direction of transmitting critical data directly to the sink node without multi-hopping of the physiological signals between intermediate nodes, which wastes the time of transmission to save patient life. This disparity between these scholars motivates us to fill the gap between them. This review article briefly discussed the state-of-the-art critical data transmission in WBANs alongside the WBANs architecture and implementation. Furthermore, a pragmatic approach to determining the threshold's degree of critical data index sensed during transmission was also considered

Congestion control mechanism for sensor-cloud Infrastructure

 This thesis has developed a sensor-Cloud system that integrates WBANs with Cloud computing to enable real-time sensor data collection, storage, processing, sharing and management. As the main contribution of this study, a congestion detection and control protocol is proposed to ensure acceptable data flows are maintained during the network lifetime

Wireless Body Area Network (WBAN): A Survey on Reliability, Fault Tolerance, and Technologies Coexistence

Wireless Body Area Network (WBAN) has been a key element in e-health to monitor bodies. This technology enables new applications under the umbrella of different domains, including the medical field, the entertainment and ambient intelligence areas. This survey paper places substantial emphasis on the concept and key features of the WBAN technology. First, the WBAN concept is introduced and a review of key applications facilitated by this networking technology is provided. The study then explores a wide variety of communication standards and methods deployed in this technology. Due to the sensitivity and criticality of the data carried and handled by WBAN, fault tolerance is a critical issue and widely discussed in this paper. Hence, this survey investigates thoroughly the reliability and fault tolerance paradigms suggested for WBANs. Open research and challenging issues pertaining to fault tolerance, coexistence and interference management and power consumption are also discussed along with some suggested trends in these aspect

Internet Data Bandwidth Optimization and Prediction in Higher Learning Institutions Using Lagrange’s Interpolation: A Case of Lagos State University of Science and Technology

This research work studies the performance of the internet services of institution of higher learning in Nigeria. Data was collated from Lagos State University of Science and Technology (LASUSTECH) as case study of this research work. The problem of Internet Bandwidth optimization in the institution of higher learning in Nigeria was extensively addressed in this paper. The operation of the Link-Load balancer which provides an efficient cost-effective and easy-to-use solution to maximize utilization and availability of Internet access is discussed. In this research work, the Lagrange’s method of interpolation was used to predict effective internet data bandwidth for significantly increasing number of internet users. The linear Lagrange’s interpolation model (LILAGRINT model) was proposed for LASUSTECH.  The predictions allow us to view the effective internet data bandwidth with respect to the corresponding acceptable number of internet users as the number of user’s increases. The integrity of the model was examined, verified and validated at the ICT department of the institution. The LILAGRINT model was integrated into the management of ICT and tested. The result showed that the proposed LILAGRINT model proved to be highly effective and innovative in the area of internet data bandwidth predictability. Keywords:Internet Data Bandwidth, Optimization, Link-load balancer, Lagrange’s interpolation, Predictions, Management of ICT DOI: 10.7176/CEIS/10-1-04 Publication date:September 30th 202

ATLAS: A Traffic Load Aware Sensor MAC Design for Collaborative Body Area Sensor Networks

In collaborative body sensor networks, namely wireless body area networks (WBANs), each of the physical sensor applications is used to collaboratively monitor the health status of the human body. The applications of WBANs comprise diverse and dynamic traffic loads such as very low-rate periodic monitoring (i.e., observation) data and high-rate traffic including event-triggered bursts. Therefore, in designing a medium access control (MAC) protocol for WBANs, energy conservation should be the primary concern during low-traffic periods, whereas a balance between satisfying high-throughput demand and efficient energy usage is necessary during high-traffic times. In this paper, we design a traffic load-aware innovative MAC solution for WBANs, called ATLAS. The design exploits the superframe structure of the IEEE 802.15.4 standard, and it adaptively uses the contention access period (CAP), contention free period (CFP) and inactive period (IP) of the superframe based on estimated traffic load, by applying a dynamic “wh” (whenever which is required) approach. Unlike earlier work, the proposed MAC design includes load estimation for network load-status awareness and a multi-hop communication pattern in order to prevent energy loss associated with long range transmission. Finally, ATLAS is evaluated through extensive simulations in ns-2 and the results demonstrate the effectiveness of the protocol