Iván Corredor

QoS in wireless sensor networks: survey and approach

A wireless sensor network (WSN) is a computer wireless network composed of spatially distributed and autonomous tiny nodes -- smart dust sensors, motes -, which cooperatively monitor physical or environmental conditions. Nowadays these kinds of networks support a wide range of applications, such as target tracking, security, environmental control, habitat monitoring, source detection, source localization, vehicular and traffic monitoring, health monitoring, building and industrial monitoring, etc. Many of these applications have strong requirements for end-to-end delay and losses during data transmissions. In this work we have classified the main mechanisms that have been proposed to provide Quality of Service (QoS) in WSN at Medium Access Control (MAC) and network layers. Finally, taking into account some particularities of the studied MAC- and network-layer protocols, we have selected a real application scenario in order to show how to choose an appropriate approach for guaranteeing performance in a WSN deployed application.

Knowledge-Aware and Service-Oriented Middleware for deploying pervasive services

Many applications and services have emerged in the frame of new Internet of Things paradigm. This novel view has opened the Web services to a variety of devices especially to tiny and resource-constrained devices. Wireless Sensor and Actuator Networks belong to that kind of devices. Those networks have become one of the more promising technologies to take part in the Future Internet. However, the integration of Sensor and Actuator Networks into the Service Cloud is a hard challenge requiring specific new architectures and protocols. This paper presents a middleware approach addressing this important issue. A Knowledge-Aware and Service-Oriented Middleware (KASOM) for pervasive embedded networks is proposed. The major aim of KASOM is to offer advanced and enriched pervasive services to everyone connected to Internet. In this sense, KASOM implements mechanisms and protocols which allow managing the knowledge generated in pervasive embedded networks in order to expose it to Internet users in a readable way. General functional requirements of embedded sensor and actuator platforms have been taken into account when designing KASOM, with special attention in energy consumption, memory and bandwidth. The KASOM evaluation and validation will be demonstrated through a real Wireless Sensor and Actuator Network deployment based on integral healthcare services in a sanatorium.

Building service-oriented Smart Infrastructures over Wireless Ad Hoc Sensor Networks: A middleware perspective

The increase in physical resources for the next-generation of embedded computing devices, as well as in the efforts carried out by the scientific and research communities, is paving the way for Smart Infrastructures based on Wireless Sensor Networks. In such manner, not only open and formally defined Service-Oriented Frameworks are required, but also efficient middleware technologies that ease the development of new sensor-based services. From the cornerstone analysis of pervasive computing principles applied to Smart Spaces creation, this article presents the @mSMS (micro Subscription Management System) middleware. This approach specifies and develops the notion of virtual sensor services created for Smart Environments over sensor networks from tiny in-network services based on agent technology. In the framework of the @mSWN European Research Project, this architecture has been validated in a Smart Hospital real-world scenario using a healthcare virtual sensor service. Considering such purpose, medical status monitoring, location tracking and perimeter surveillance agent-based services have been developed. This study is concluded by a comparative analysis of the system considering memory overhead, packet delivery ratio, average end-to-end delay and battery lifetime as evaluation metrics. The results show a lightweight middleware implementation with good overall system and network performance.

Bringing pervasive embedded networks to the service cloud: A lightweight middleware approach

The emergence of novel pervasive networks that consist of tiny embedded nodes have reduced the gap between real and virtual worlds. This paradigm has opened the Service Cloud to a variety of wireless devices especially those with sensorial and actuating capabilities. Those pervasive networks contribute to build new context-aware applications that interpret the state of the physical world at real-time. However, traditional Service-Oriented Architectures (SOA), which are widely used in the current Internet are unsuitable for such resource-constraint devices since they are too heavy. In this research paper, an internetworking approach is proposed in order to address that important issue. The main part of our proposal is the Knowledge-Aware and Service-Oriented (KASO) Middleware that has been designed for pervasive embedded networks. KASO Middleware implements a diversity of mechanisms, services and protocols which enable developers and business processing designers to deploy, expose, discover, compose, and orchestrate real-world services (i.e. services running on sensor/actuator devices). Moreover, KASO Middleware implements endpoints to offer those services to the Cloud in a REST manner. Our internetworking approach has been validated through a real healthcare telemonitoring system deployed in a sanatorium. The validation tests show that KASO Middleware successfully brings pervasive embedded networks to the Service Cloud.

Composition and deployment of e-Health services over Wireless Sensor Networks

Providing necessary background for provisioning of a new generation of enriched services over Wireless Sensor Networks is the main effort that the scientific community is currently carrying out. These services have improved a great number of aspects related to pervasive systems such as saving resources, efficiency, reliability, scalability and low power consumption. In this paper, @mSMS middleware, using an event-based service model, is presented. This novel approach makes up the design requirements previously mentioned by implementing a dynamic memory kernel and a variable payload multiplexing mechanism for the information events in order to provide advanced services. The results obtained over real-world deployments, especially those related with provision of e-Health services, reflect a significant improvement over other similar proposals, such as the RUNES approach: 50% lower memory overhead, 53% lower software components load time and 12% lower events propagation time.

A Lightweight Web of Things Open Platform to Facilitate Context Data Management and Personalized Healthcare Services Creation

In the last few years, many health monitoring systems have been designed to fullfil the needs of a large range of scenarios. Although many of those systems provide good ad hoc solutions, most of them lack of mechanisms that allow them to be easily reused. This paper is focused on describing an open platform, the micro Web of Things Open Platform (µWoTOP), which has been conceived to improve the connectivity and reusability of context data to deliver different kinds of health, wellness and ambient home care services. µWoTOP is based on a resource-oriented architecture which may be embedded in mobile and resource constrained devices enabling access to biometric, ambient or activity sensors and actuator resources through uniform interfaces defined according to a RESTful fashion. Additionally, µWoTOP manages two communication modes which allow delivering user context information according to different methods, depending on the requirements of the consumer application. It also generates alert messages based on standards related to health care and risk management, such as the Common Alerting Protocol, in order to make its outputs compatible with existing systems.

Model-Driven Methodology for Rapid Deployment of Smart Spaces Based on Resource-Oriented Architectures

Advances in electronics nowadays facilitate the design of smart spaces based on physical mash-ups of sensor and actuator devices. At the same time, software paradigms such as Internet of Things (IoT) and Web of Things (WoT) are motivating the creation of technology to support the development and deployment of web-enabled embedded sensor and actuator devices with two major objectives: (i) to integrate sensing and actuating functionalities into everyday objects, and (ii) to easily allow a diversity of devices to plug into the Internet. Currently, developers who are applying this Internet-oriented approach need to have solid understanding about specific platforms and web technologies. In order to alleviate this development process, this research proposes a Resource-Oriented and Ontology-Driven Development (ROOD) methodology based on the Model Driven Architecture (MDA). This methodology aims at enabling the development of smart spaces through a set of modeling tools and semantic technologies that support the definition of the smart space and the automatic generation of code at hardware level. ROOD feasibility is demonstrated by building an adaptive health monitoring service for a Smart Gym.

An Open Architecture to Enhance Pervasiveness and Mobility of Health Care Services

This paper describes a system for ubiquitous monitoring of health and physical parameters, suitable to run on home-based infrastructures and personal mobile settings. The system is built on a micro Web of Things Open Platform (μWoTOP), enabling easy integration of sensing and processing modules. It also facilitates building ubiquitous services by accessing biometric sensors through uniform interfaces based on REST. Additionally, the system is capable of processing user context and generate alerts based on the Common Alerting Protocol, making its output compatible with already existing medical solutions. The system has been customized to deploy a fall/faint detection solution, which enables multiple supervisors with the capability of receiving real time alerts on monitored subjects.

The DiY Smart Experiences Project

In this chapter we discuss the wide range of challenges in user-generated Internet of Things applications, as being worked on among the large consortium of the DiY Smart Experiences (DiYSE) project (DiYSE, ITEA2 08005). The chapter starts with a discussion on the context of ‘DiY’ as a phenomenon to be leveraged, and eco-awareness as an example application area. The main body of the chapter is devoted to the technical outline of the DiYSE architecture, starting at the lower Internet of Things layers of sensors, actuators and middleware, over the role of semantics in device and service interoperability, up to requirements for the service framework and the application creation process. Furthermore, the chapter adds considerations concerning tangible interaction in the smart space, assumed in Di- YSE both for the context of experiencing as well as shaping the user experience. With the chapter, we thus take a holistic view, sampling the range from lowerlayer technical implications of enabling DiY creation in the Internet of Things, up to the human-level aspects of creative communities as well as tangible interaction.

Modelling QoS for wireless sensor networks

A wireless sensor network (WSN) is a wireless network composed of spatially distributed and tiny autonomous nodes — smart dust sensors, motes —, which cooperatively monitor physical or environmental conditions. Nowadays these kinds of networks support a wide range of applications, such as target tracking, security, environmental control, habitat monitoring, source detection, source localization, vehicular and traffic monitoring, health monitoring, building and industrial monitoring, etc. Generally, these applications have strong and strict requirements for end-to-end delaying and loosing during data transmissions. In this paper, we propose a realistic scenario for application of the WSN field in order to illustrate selection of an appropriate approach for guaranteeing performance in a WSN-deployed application. The methodology we have used includes four major phases: 1) Requirements analysis of the application scenario; 2) QoS modeling in different layers of the communications protocol stack and selection of more suitable QoS protocols and mechanisms; 3) Definition of a simulation model based on an application scenario, to which we applied the protocols and mechanisms selected in the phase 2; and 4) Validation of decisions by means of simulation and analysis of results. This work has been partially financed by the “Universidad Politecnica de Madrid” and the “ Comunidad de Madrid” in the framework of the project CRISAL - M0700204174.