Hyggo Oliveira de Almeida

A UPnP extension for enabling user authentication and authorization in pervasive systems

The Universal Plug and Play (UPnP) specification defines a set of protocols for promoting pervasive network connectivity of computers and intelligent devices or appliances. Nowadays, the UPnP technology is becoming popular due to its robustness to connect devices and the large number of developed applications. One of the major drawbacks of UPnP is the lack of user authentication and authorization mechanisms. Thus, control points, those devices acting as clients on behalf of a user, and UPnP devices cannot communicate based on user information. This paper introduces an extension of the UPnP specification called UPnP-UP, which allows user authentication and authorization mechanisms for UPnP devices and applications. These mechanisms provide the basis to develop customized and secure UPnP pervasive services, maintaining backward compatibility with previous versions of UPnP.

A flexible middleware for service provision over heterogeneous pervasive networks

Pervasive computing has gained much attention from the research community due to the possibility of deploying the first pervasive environments. Therefore, many software solutions are emerging, with the intent of facilitating the development of pervasive applications. Within this scope, in this paper, we introduce a service oriented middleware for pervasive computing, enhanced with runtime flexibility, extensibility for applications, and heterogeneous service provision. Our goal is to enable the middleware and its applications to be adapted to changing operational scenarios. Furthermore, different protocols can be used to discover and access services

A personal connected health system for the Internet of Things based on the Constrained Application Protocol

Display Omitted We present a system that enables Personal Health Devices to share information in home networks and with the Internet.The Constrained Application Protocol (CoAP) is used as underlying protocol.The CoAP communication model was adapted to the ISO/IEEE 11073 model in the proposed system.Results showed how the network overhead is around 50% lighter when compared to other protocols.Interoperability experiments demonstrated how the proposed solution can work with legacy systems. The increasing costs of healthcare along with the increasing availability of new Personal Health Devices (PHDs) are the ingredients of the connected health vision. Also, a growing number of consumer electronic and mobile devices are becoming capable of taking the role of a health gateway, thus operating as a data collector for PHDs. In this context, we present a system that enables PHDs to share information in home networks and with the Internet based on a new Internet of Things protocol, namely the Constrained Application Protocol (CoAP). CoAP is used along with the IEEE 11073 family of standards, which is the main exchange data model for PHD communication. We discuss how the proposed system can be integrated to other connected health systems, such as a Universal Plug and Play healthcare system. We detail how the CoAP communication model was adapted to the IEEE 11073 model. We also present a real PHD prototype and its evaluation results. These results demonstrated the feasibility of the proposed solution, showing how its network overhead is around 50% lighter when compared to other protocols. Finally, we tested the proposed solution based on different scenarios, including a proof-of-concept integration with a service in the cloud, using different wireless physical interfaces.

Integrating MQTT and ISO/IEEE 11073 for health information sharing in the Internet of Things

The Internet of Things (IoT) paradigm allows small and resource constrained devices to send data through complex networks like the Internet. Bringing the IoT paradigm to the healthcare area, we can expand the connected health vision, enabling new Personal Health Devices (PHD) to share health information directly through the Internet. In this paper we explore the use of the MQTT (Message Queue Telemetry Transport) lightweight protocol together with the ISO/IEEE 11073 standard. We present new ways of connecting PHDs in home networks and the Internet by the use of MQTT Brokers, which will reduce the amount of data traffic.

On the performance of TCP, UDP and DCCP over 802.11 g networks

This paper presents an experimental study of streaming multimedia packets using DCCP transport protocol over 802.11 g networks. Our main focus is to study the behavior of DCCP flows over real-time multimedia applications. The approach taken was to use DCCP flows in the presence of TCP and UDP flows, then analyze the behavior of each protocol, mainly in regards to the congestion control algorithms of both protocols. Furthermore, we also considered end-points mobility requirements, such as hand-off between multiples access points. Needless to say, the DCCP protocol was recently standardized by IETF as an alternative for streaming multimedia flows on computer networks. The results presented in this paper show that TCP and DCCP protocols can share the network bandwidth without affecting each other. On the other hand, UDP flows can aggressively degrade TCP and DCCP flows due to the absence of any kind of flow control. Although UDP flows reach high bandwidth throughput, it loses a considerable amount of data taking into account limited bandwidth channels, such as 802.11g networks. Finally, this work also shows that TCP and DCCP can think of loss of packets as network congestion while experimenting hand-offs, thus decreasing their throughput.

A model to detect problems on scrum-based software development projects

There is a high rate of software development projects that fails. Whenever problems can be detected ahead of time, software development projects may have better chances of success, and therefore save money and time. In this paper, we present a probabilistic model to help ScrumMasters to apply Scrum in organizations. The models goal is to provide information to the projects ScrumMaster to help him to be aware of the projects problems and have enough information to guide the team and improve the projects chances of success. We published a survey to collect data for this study and validated the model by applying it to scenarios. The results obtained so far show that the model is promising.

Early diagnosis of gastrointestinal cancer by using case-based and rule-based reasoning

We present a medical diagnosis decision support model for gastrointestinal cancer.The model uses case-based reasoning (CBR) and rule-based reasoning (RBR).We used real patient data as inputs to our model.The model was validated through K-fold cross validation and the paired t-test.Improved diagnosis accuracy compared to a CBR approach not using RBR in retrieval. In this paper, we present a medical diagnosis decision support model for gastrointestinal cancer. It should be used by general practitioners whenever there is a suspicion that a patient has this type of cancer. To build our model, we used Case-Based Reasoning (CBR) and Rule-Based Reasoning (RBR). We used real patient data as inputs to our model. We applied RBR to improve the CBR retrieve process. The models output presents the probability of the patient having a specific cancer. In order to adjust the attributes weights, we collected data from a general practitioner. To validate our model, we used K-fold cross validation and the paired t-test. The results showed that, with our approach, the accuracy of the diagnosis increased by 22.92% when compared to a CBR approach not using RBR in case retrieval. Furthermore, we evaluated our approach with an online questionnaire and semi-structured interviews. Even though, given the number of respondents, we cannot generalize our conclusions, the results indicate that our approach would be useful for general practitioners.

Towards the UPnP-UP: Enabling User Profile to Support Customized Services in UPnP Networks

In a nutshell, UPnP aims to enable simple and robust connectivity among consumer electronics, intelligent appliances and mobile devices from many different vendors. Nowadays, it is getting an increasing popularity due to its robust way of connecting devices and the massive number of already developed applications, complementing the useful new era of pervasive computing. Although UPnP is an easy-to-use solution for discovery, which allows controlled devices to share and access users contents, it does neither provide user authentication nor authorization mechanisms, requirements that would require users data on personal profiles. As a consequence, we propose an extension of the UPnP protocol called UPnP-UP, which allows user authentication and authorization for UPnP devices and applications. The primary goal of our proposed extension is to modify the current UPnP specification as less as possible, maintaining backwards compatibility with previous versions of the protocol. Furthermore, we present our efforts on the development of a UPnP framework for publishing and accessing multimedia contents in order to support this extension as a case of study.

Improving flexibility on host discovery for pervasive computing middlewares

The vision of pervasive or ubiquitous computing, conceived by Mark Weiser, foresees a world where computing is embedded in every day objects. Such objects interact with each other to perform actions on behalf of the user. As one of the mains of pervasive computing is to disappear from human perception, applications embedded in electronic devices must be proactive. This indicates that they should guess the needs of the users in order to provide them with anytime, anywhere relevant information. This characteristic must be achieved by acquiring information not only about the user, but also about the environment where he/she is immersed. This kind of information can be obtained by interacting with nearby hosts, trough a variety of networking protocols. Applications can take advantage of this characteristic by performing host discovery through heterogeneous networks, possibly at the same time. However, due to memory and storage constraints, it is not reasonable to embed all of such protocols in a mobile device. Therefore, we propose a flexible mechanism for performing host discovery in pervasive environments, allowing the insertion and removal of these networking protocols whenever needed.

A Model-Based Approach to Support Validation of Medical Cyber-Physical Systems

Medical Cyber-Physical Systems (MCPS) are context-aware, life-critical systems with patient safety as the main concern, demanding rigorous processes for validation to guarantee user requirement compliance and specification-oriented correctness. In this article, we propose a model-based approach for early validation of MCPS, focusing on promoting reusability and productivity. It enables system developers to build MCPS formal models based on a library of patient and medical device models, and simulate the MCPS to identify undesirable behaviors at design time. Our approach has been applied to three different clinical scenarios to evaluate its reusability potential for different contexts. We have also validated our approach through an empirical evaluation with developers to assess productivity and reusability. Finally, our models have been formally verified considering functional and safety requirements and model coverage.