Miguel Almeida

Mobility with QoS Support for Multi-Interface Terminals: Combined User and Network Approach

In the future, mobile terminals will be equipped with several interfaces to different technologies -such as UMTS, IEEE 802.11, DVB and WiMAX -and will be able to connect simultaneously to the most appropriate access networks. This paper presents a mobility and QoS architecture aiming at supporting intelligent handovers. We introduce the concept of Network-Assisted Mobile terminal Initiated HandOver (NAMIHO), where the handover decision is negotiated between the network and the user, taking into account inputs and decision algorithms running both on the terminal and network. We also present an instantiation of the architecture using IEEE 802.21 and concepts of local/global mobility. We further propose extensions to IEEE 802.21 standard.

Bridging the Devices with the Web Cloud: A Restful Management Architecture over XMPP

In this paper we deal with the interactions between different types of devices and a SaaS (Software as a Service) Management System. It is our goal to provide a generic way by which users interface with their devices in terms of getting information and actually being able to communicate with them. Our effort in this proposal is the establishment of these interactions while assuring a set of requirements such as privacy, authentication, association of multiple devices to a user, etc. We provide the architectural means to support this view and ensure the communication of the IoT (Internet of Things) devices with a Cloud of Web Services, while maintaining the M2M (Machine 2 Machine) vision. To do so we define an entity, the Cloud Bridge Server, which uses the Extensible Messaging and Presence Protocol (XMPP) to interact with the devices, and which provides a Representational State Transfer (REST) API for 3rd party Web Services. We present results on how our approach performs when facing other alternatives and the main advantages of using it.

3D-2D laser range finder calibration using a conic based geometry shape

The AtlasCar is a prototype that is being developed at the University of Aveiro to research advanced driver assistance systems. The car is equipped with several sensors: 3D and 2D laser scanners, a stereo camera, inertial sensors and GPS. The combination of all these sensor data in useful representations is essential. Therefore, calibration is one of the first problems to tackle. This paper focuses on 3D/2D laser calibration. The proposed method uses a 3D Laser Range Finder (LRF) to produce a reference 3D point cloud containing a known calibration object. Manual input from the user and knowledge of the object geometry are used to register the 3D point cloud with the 2D Lasers. Experimental results with simulated and real data demonstrate the effectiveness of the proposed calibration method.

Cross layer design approach for performance evaluation of multimedia contents

Service Performance Evaluation is usually associated with connectivity related services, such as the provisioning of an internet connection. Now operators are beginning to explore new business opportunities on the All-over-IP world and beyond. New solutions are being deployed focusing on the multimedia interactive contents. New network architectures will require extensions to provide a clear vision on the service delivery quality, and new approaches on cross-layer information will be envisioned. This paper provides an insight on the cross-layer overview of the current 3GPP networks, while featuring the analysis until the end-to-end performance and end-user perception. It employs a correlation between the most relevant parameters at each layer and underlines their contribution to the upper layers. It further provides an analytical qualitative analysis of the overall service performance by evaluating simulation results which are sustained by both network and service performance metrics.

Experimental evaluation of the usage of ad hoc networks as stubs for multiservice networks

This paper describes an experimental evaluation of a multiservice ad hoc network, aimed to be interconnected with an infrastructure, operator-managed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad hoc network. It contains the following functionalities: routing and delivery of unicast and multicast services; distributed QoS mechanisms to support service differentiation and resource control responsive to node mobility; security, charging, and rewarding mechanisms to ensure the correct behaviour of the users in the ad hoc network. This paper experimentally evaluates the performance of multiple mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. The performance results obtained in the different real scenarios may question the real usage of ad-hoc networks for more than a minimal number of hops with such a large number of functionalities deployed.

Media Independent End User Behavior and Performance Reports

This paper proposes an architecture to provide seamless reporting over heterogeneous networks while focusing on the End-to-End information exchange and Quality of Experience analysis. For this purpose, it is presented a reporting architecture based on IEEE 802.21, where the reports are seamless exchanged through new extended IEEE 802.21 messages. This approach, besides saving on overhead of service and end-users reporting, is able to seamless support reporting through heterogeneous technologies, in multiple layers, while integrating both actions of reporting and network reaction, through IEEE 802.21. This new framework balances the impact of the signaling over the network load, representing a good lightweight trade off when comparing to other solutions, while still being able to deploy new business cases.

Coupling Activity and Performance Management with Mobility in Vehicular Networks

We live in a mobile, fast paced world, where users are constantly on the move. Transportation plays a major role in this matter. Users thrive for services being promptly delivered anytime and anywhere. Nevertheless, business models still focus around Content Service Providers (CSP) and Network Service Providers (NSP), who, as trusted entities, provide more than the connection, further focusing, as time evolves, on the service delivery capitalization. As the trends start to position these providers as the relay points for the information to be conveyed into 3rd party cloud services, the delegation of management functions is also outsourced to the 3rd party entities. It is in this view that the remote management of vehicles becomes of the utmost importance, since connectivity allows the delivery of novel services built around the monitoring of the vehicles’ conditions, location and user preferences. The immediate benefits would result in presence/location awareness for retrieval of additional information of the surroundings, or even mechanical support, mechanical failure prediction or detection, based on the continuous monitoring of the vehicles hardware sensors, as well as a whole plethora of new advantages, propelled by the collection of performance and behavior information. Vehicular networks are inherently associated with high mobility scenarios and this fact introduces new requirements. Usually associated with high velocity patterns, the requirements to support these networks are mainly positioned around the enabling of fast mobility management protocols, and hence interfaces, gifted with the extensibility potential for the exchange of additional information. Furthermore, when considering vehicular scenarios, network mobility and efficiency are two crucial features which need to be kept in mind at all times. They have special influence over the choice of the protocol used to gather information from the vehicles towards the network. These requirements lead us to consider a framework that was originally designed for the management of the mobility of the terminals, and which therefore supports mobility with a high efficiency ratio in terms of resource consumption. This framework, the IEEE 802.21 Media Independent Handovers (802.21-2008, 2009), contains functionalities and elements that can be extended with advanced reporting capabilities to provide seamless reporting in heterogeneous technologies and environments. Using IEEE 802.21, it is also possible to integrate the actions of reporting with the actions of network decisions enforcement. We show that this approach provides a significant set of functionalities not achieved with current approaches, while reducing the overhead on cross-layer reporting. The typical approach is to perform such procedures above the IP layer. 5