Paulo R. S. L. Coelho

Design and Implementation Issues for Modern Remote Laboratories

The design and implementation of remote laboratories present different levels of complexity according to the nature of the equipments operated by the remote laboratory, the requirements imposed on the accessing computers, the network linking the user to the laboratory, and the type of experiments the laboratory supports. This paper addresses the design and implementation of remote laboratories employing web technologies, both at the client and the server side. These types of remote laboratories are called WebLabs, and can be deployed over different networks such as the public internet, campuswide networks, or high-speed private networks. Although most published works on WebLabs focus on their functional and operational aspects, nonfunctional requirements related to security, quality of service, and federated operation of WebLabs have received little attention. This paper addresses how these requirements can be incorporated into WebLab design, and discusses the most appropriate web technologies to fulfill such requirements.

A Web Lab for Mobile Robotics Education

This paper presents an architecture for building remote access laboratories (or Web labs) following the service-oriented computing approach. In this architecture the applications building blocks are services that can be recursively composed resulting in more comprehensive services. Remote access laboratories can benefit of this approach. Every lab resource (physical or logical) is modeled and implemented as a service (in our case, a Web service) and lab experiments are assembled by composing these services. A Web lab built according to this architecture is presented with examples of remote experiments in the field of mobile robotics.

A network architecture for large mobile robotics environments

Mobile robotics environments must adopt networking solutions that provide secure and reliable communications for the mobile robots across wide areas such as hospitals, factories, farms, etc. This paper proposes a network architecture for large mobile robotic environments built above the existing networking infrastructures. The architecture builds an overlay network above the already deployed network. The overlay network must fulfill the requirements demanded by mobile robotic applications, mainly, communication continuity during handover, security, and quality of service. A prototype of this architecture was implemented and evaluated in a mobile robotic environment composed of Pioneer P3-DX mobile robots accessed through the Internet. Results from simulation show that the architecture scales well in larger networking scenarios.

An Architecture for Traffic Sign Management in Smart Cities

This paper introduces and evaluates a Traffic Sign Management Architecture (TSMA), which represents a paradigm shift for the deployment of traffic sign infrastructure in the context of Intelligent Transport Systems, Vehicular Networks and Smart Cities. The proposal addresses limitations of the current traffic control model by enabling remote updates of traffic signs and displaying them on the vehicular navigation system display to improve their legibility. TSMA is an architecture developed to provide V2I interaction using a commodity technology, Wi-Fi, through the beacon-stuffing technique. The initial design of TSMAs security mechanisms is also presented in this paper. Evaluations were performed on a developed prototype and simulation environments.

A Platform for Monitoring Service-Level Metrics in Software Defined Networks

This paper presents and evaluates a platform for monitoring service-level metrics in OpenFlow Software Defined Networks (SDN), named SDNMon. The platform supports frequent network observation, at different granularity levels, including per-flow observation, being able to present accurate on-the-fly statistics regarding throughput and delay. The evaluation considered two statistical data gathering approaches, a proposed polling-based mechanism which collects information kept by OpenFlow counters at the network elements, and an alternate sampling-based mechanism which uses sFlow.

ASN-FWD: Shrinking the IPv4 Share on the Forwarding Information Base

This paper presents a proposal for shrinking the number of IPv4 FIB (Forwarding Information Base) entries required on routers. Traffic forwarding under the proposed mechanism is based on the current ASNs (Autonomous System Numbers), and can be gradually adopted by ISPs.We find that, at the cost of adding 8 bytes per packet, the proposed ASN-FWD technique is capable of providing full IPv4 traffic forwarding based on ASN information, which is correspondent to 10% of the current number of IPv4 prefixes present on FIB of routers. Among its main benefits, the proposed approach alleviates the pressure on the amount of FIB shipped on routers, and paves the way for a worldwide adoption of IPv6.

Node Position Forecast in MANET with PheroCast

In mobile ad hoc networks (MANET) nodes are free to move on the environment and interact with each other and with the infra-structure, enabling a multitude of applications and services. However, the same mobility that is key to MANET is also the greater limiting factor in the quality of the services provided in this environment, since the infrastructure must keep adapting to the mobility. This paper describes algorithms for predicting the future position of mobile nodes in MANET, allowing the infrastructure to proactively adapt. Our algorithms maintain the recent movement history of nodes in a compact representation, a graph, based on stigmergy of ant colonies. Predictions are generated through a limited depth first search. We have experimented this method against real world data and the results show that the prediction is accurate for short time horizons (30 seconds) in a metropolitan area (Seattle) divided in a grid of two or three-block square cells, in 77.8% of the cases. This method may be used in optimizing MANET and enabling novel applications, for example, proactive hand-off, tailored content generation, and proactive routing.