Detecting Non-Line of Sight to Prevent Accidents in Vehicular Ad hoc Networks

There are still many challenges in the field of VANETs that encouraged researchers to conduct further investigation in this field to meet these challenges. The issue pertaining to routing protocols such as delivering the warning messages to the vehicles facing Non-Line of Sight (NLOS) situations without causing the storm problem and channel contention, is regarded as a serious dilemma which is required to be tackled in VANET, especially in congested environments. This requires the designing of an efficient mechanism of routing protocol that can broadcast the warning messages from the emergency vehicles to the vehicles under NLOS, reducing the overhead and increasing the packet delivery ratio with a reduced time delay and channel utilisation. The main aim of this work is to develop the novel routing protocol for a high-density environment in VANET through utilisation of its high mobility features, aid of the sensors such as Global Positioning System (GPS) and Navigation System (NS). In this work, the cooperative approach has been used to develop the routing protocol called the Co-operative Volunteer Protocol (CVP), which uses volunteer vehicles to disseminate the warning message from the source to the target vehicle under NLOS issue; this also increases the packet delivery ratio, detection of NLOS and resolution of NLOS by delivering the warning message successfully to the vehicle under NLOS, thereby causing a direct impact on the reduction of collisions between vehicles in normal mode and emergency mode on the road near intersections or on highways. The cooperative approach adopted for warning message dissemination reduced the rebroadcast rate of messages, thereby decreasing significantly the storm issue and the channel contention. A novel architecture has been developed by utilising the concept of a Context-Aware System (CAS), which clarifies the OBU components and their interaction with each other in order to collect data and take the decisions based on the sensed circumstances. The proposed architecture has been divided into three main phases: sensing, processing and acting. The results obtained from the validation of the proposed CVP protocol using the simulator EstiNet under specific conditions and parameters showed that performance of the proposed protocol is better than that of the GRANT protocol with regard to several metrics such as packet delivery ratio, neighbourhood awareness, channel utilisation, overhead and latency. It is also successfully shown that the proposed CVP could detect the NLOS situation and solves it effectively and efficiently for both the intersection scenario in urban areas and the highway scenario

A layered security approach for cooperation enforcement in MANETs

In fully self-organized MANETs, nodes are naturally reluctant to spend their precious resources forwarding other nodes' packets and are therefore liable to exhibit selfish or sometimes malicious behaviour. This selfishness could potentially lead to network partitioning and network performance degradation. Cooperation enforcement schemes, such as reputation and trust based schemes have been proposed to counteract the issue of selfishness. The sole purpose of these schemes is to ensure selfish nodes bear the consequences of their bad actions. However, malicious nodes can exploit mobility and free identities available to breach the security of these systems and escape punishment or detection. Firstly, in the case of mobility, a malicious node can gain benefit even after having been detected by a reputation-based system, by interacting directly with its source or destination nodes. Secondly, since the lack of infrastructure in MANETs does not suit centralized identity management or centralized Trusted Third Parties, nodes can create zero-cost identities without any restrictions. As a result, a selfish node can easily escape the consequences of whatever misbehaviour it has performed by simply changing identity to clear all its bad history, known as whitewashing. Hence, this makes it difficult to hold malicious nodes accountable for their actions. Finally, a malicious node can concurrently create and control more than one virtual identity to launch an attack, called a Sybil attack. In the context of reputation-based schemes, a Sybil attacker can disrupt the detection accuracy by defaming other good nodes, self-promoting itself or exchanging bogus positive recommendations about one of its quarantined identities. This thesis explores two aspects of direct interactions (DIs), i. e. Dis as a selfish nodes' strategy and Dis produced by inappropriate simulation parameters. In the latter case DIs cause confusion in the results evaluation of reputation-based schemes. We propose a method that uses the service contribution and consumption information to discourage selfish nodes that try to increase their benefit through DIs. We also propose methods that categorize nodes' benefits in order to mitigate the confusion caused in the results evaluation. A novel layered security approach is proposed using proactive and reactive paradigms to counteract whitewashing and Sybil attacks. The proactive paradigm is aimed at removing the advantages that whitewashing can provide by enforcing a non-monetary entry fee per new identity, in the form of cooperation in the network. The results show that this method deters these attackers by reducing their benefits in the network. In the reactive case, we propose a lightweight approach to detect new identities of whitewashers and Sybil attackers on the MAC layer using the 802.11 protocol without using any extra hardware. The experiments show that a signal strength based threshold exists which can help us detect Sybil and whitewashers' identities. Through the help of extensive simulations and real-world testbed experimentations, we are able to demonstrate that our proposed solution detects Sybil or whitewashers' new identities with good accuracy and reduces the benefits of malicious activity even in the presence of mobility

An architectural framework for self-configuration and self-improvement at runtime

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Augmented reality device for first response scenarios

A prototype of a wearable computer system is proposed and implemented using commercial off-shelf components. The system is designed to allow the user to access location-specific information about an environment, and to provide capability for user tracking. Areas of applicability include primarily first response scenarios, with possible applications in maintenance or construction of buildings and other structures. Necessary preparation of the target environment prior to system\u27s deployment is limited to noninvasive labeling using optical fiducial markers. The system relies on computational vision methods for registration of labels and user position. With the system the user has access to on-demand information relevant to a particular real-world location. Team collaboration is assisted by user tracking and real-time visualizations of team member positions within the environment. The user interface and display methods are inspired by Augmented Reality1 (AR) techniques, incorporating a video-see-through Head Mounted Display (HMD) and fingerbending sensor glove.*. 1Augmented reality (AR) is a field of computer research which deals with the combination of real world and computer generated data. At present, most AR research is concerned with the use of live video imagery which is digitally processed and augmented by the addition of computer generated graphics. Advanced research includes the use of motion tracking data, fiducial marker recognition using machine vision, and the construction of controlled environments containing any number of sensors and actuators. (Source: Wikipedia) *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Adobe Acrobat; Microsoft Office; Windows MediaPlayer or RealPlayer

Hybrid intelligent decision support system for distributed detection based on ad hoc integrated WSN & RFID

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonThe real time monitoring of environment context aware activities, based on distributed detection, is becoming a standard in public safety and service delivery in a wide range of domains (child and elderly care and supervision, logistics, circulation, and other). The safety of people, goods and premises depends on the prompt immediate reaction to potential hazards identified in real time, at an early stage to engage appropriate control actions. Effective emergency response can be supported only by available and acquired expertise or elaborate collaborative knowledge in the domain of distributed detection that include indoor sensing, tracking and localizing. This research proposes a hybrid conceptual multi-agent framework for the acquisition of collaborative knowledge in dynamic complex context aware environments for distributed detection. This framework has been applied for the design and development of a hybrid intelligent multi-agent decision system (HIDSS) that supports a decentralized active sensing, tracking and localizing strategy, and the deployment and configuration of smart detection devices associated to active sensor nodes wirelessly connected in a network topology to configure, deploy and control ad hoc wireless sensor networks (WSNs). This system, which is based on the interactive use of data, models and knowledge base, has been implemented to support fire detection and control access fusion functions aimed at elaborating: An integrated data model, grouping the building information data and WSN-RFID database, composed of the network configuration and captured data, A virtual layout configuration of the controlled premises, based on using a building information model, A knowledge-based support for the design of generic detection devices, A multi-criteria decision making model for generic detection devices distribution, ad hoc WSNs configuration, clustering and deployment, and Predictive data models for evacuation planning, and fire and evacuation simulation. An evaluation of the system prototype has been carried out to enrich information and knowledge fusion requirements and show the scope of the concepts used in data and process modelling. It has shown the practicability of hybrid solutions grouping generic homogeneous smart detection devices enhanced by heterogeneous support devices in their deployment, forming ad hoc networks that integrate WSNs and radio frequency identification (RFID) technology. The novelty in this work is the web-based support system architecture proposed in this framework that is based on the use of intelligent agent modelling and multi-agent systems, and the decoupling of the processes supporting the multi-sensor data fusion from those supporting different context applications. Although this decoupling is essential to appropriately distribute the different fusion functions, the integration of several dimensions of policy settings for the modelling of knowledge processes, and intelligent and pro-active decision making activities, requires the organisation of interactive fusion functions deployed upstream to a safety and emergency response.Saudi government, represented by the Ministry of Interior and General Directorate of Civil Defenc

Design and implementation of a cognitive node for heterogeneous wireless ad-hoc

In this thesis, the design of a cognitive network layer solution for a scenario with mobile devices is presented. Cognitive networks are able to sense the environment and adapt in order to find the best performance of the network at any moment. The final objective is to carry out a design of a node of the network which has incorporated in it up to three different technologies, which are WLAN, Bluetooth and ZigBee. The node is able to determine whether a technology should be used or not based on the network state. In order to find out the network state, a routing protocol based on Link State to provide the full view of the network is designed. Adaptive routing metrics have been designed in order to determine the best performance of the network to meet the QoS requirements considering what service is being required by the application and therefore to choose what technology is more appropriated for the connection. Those metrics are based on the capacity of the link, which takes into account the technology, the delay and the packet error rate of itself, and the utilization level. Then, Dijkstras’ algorithm is computed to solve the routing problem based on the adaptive weights instead of using the traditional hop-based count as a cost function. Furthermore, a heterogeneous cognitive wireless ad-hoc network testbed is implemented to analyze the behavior of the cognitive network when different types of services are used. On top of the cognitive network layer, an application to arrange meetings is implemented. Meeting rooms offer two different type of service for the guests, video and data service. Thus, clients are able to configure a video conference with the meeting room in case they cannot attend the meeting

Augmented Worlds: a proposal for modelling and engineering pervasive mixed reality smart environments

In recent years, the remarkable technological advancement has revolutionised the ICT panorama offering nowadays the opportunity to exploit several technological convergences to reduce the gulf existing between the physical and the digital matter, between the physical real world and every computational software system or application. Along with Pervasive Computing - entered in the mainstream with the concept of Internet of Things (IoT) - Mixed Reality (MR) is going to be an essential ingredient for the design and development of next future smart environments. In particular, in such environments is feasible to imagine that the computation will drive the augmentation of the physical space, and software will also be executed in a cyber-physical world, eventually populated with of (interactive) holograms. After an initial exploration of the state of the art about augmentation technologies both for humans and the environment, in this dissertation we present the vision of Augmented Worlds (AW), a conceptual and a practical proposal for modelling and engineering next future pervasive mixed reality smart environments as distribute, multi-user and cooperative complex software systems. On the one hand, a meta-model is formalised and opportunely discussed to offer to the literature a conceptual tool for modelling AWs. On the other hand, also a concrete infrastructure - called MiRAgE - is designed and developed to produce a platform for engineering and deploy such innovative smart environments. The work carried out in this dissertation fits into the scientific literature and research of Pervasive Computing and Mixed Reality fields. Furthermore, part of the contribution is related also to the area of Cognitive Agents and Multi-Agent Systems, due to the AWs orientation to be deeply connected to a layer involving autonomous agents able to observe and act proactively in the smart environment