A cross-layer middleware architecture for time and safety critical applications in MANETs

Mobile Ad hoc Networks (MANETs) can be deployed instantaneously and adaptively, making them highly suitable to military, medical and disaster-response scenarios. Using real-time applications for provision of instantaneous and dependable communications, media streaming, and device control in these scenarios is a growing research field. Realising timing requirements in packet delivery is essential to safety-critical real-time applications that are both delay- and loss-sensitive. Safety of these applications is compromised by packet loss, both on the network and by the applications themselves that will drop packets exceeding delay bounds. However, the provision of this required Quality of Service (QoS) must overcome issues relating to the lack of reliable existing infrastructure, conservation of safety-certified functionality. It must also overcome issues relating to the layer-2 dynamics with causal factors including hidden transmitters and fading channels. This thesis proposes that bounded maximum delay and safety-critical application support can be achieved by using cross-layer middleware. Such an approach benefits from the use of established protocols without requiring modifications to safety-certified ones. This research proposes ROAM: a novel, adaptive and scalable cross-layer Real-time Optimising Ad hoc Middleware framework for the provision and maintenance of performance guarantees in self-configuring MANETs. The ROAM framework is designed to be scalable to new optimisers and MANET protocols and requires no modifications of protocol functionality. Four original contributions are proposed: (1) ROAM, a middleware entity abstracts information from the protocol stack using application programming interfaces (APIs) and that implements optimisers to monitor and autonomously tune conditions at protocol layers in response to dynamic network conditions. The cross-layer approach is MANET protocol generic, using minimal imposition on the protocol stack, without protocol modification requirements. (2) A horizontal handoff optimiser that responds to time-varying link quality to ensure optimal and most robust channel usage. (3) A distributed contention reduction optimiser that reduces channel contention and related delay, in response to detection of the presence of a hidden transmitter. (4) A feasibility evaluation of the ROAM architecture to bound maximum delay and jitter in a comprehensive range of ns2-MIRACLE simulation scenarios that demonstrate independence from the key causes of network dynamics: application setting and MANET configuration; including mobility or topology. Experimental results show that ROAM can constrain end-to-end delay, jitter and packet loss, to support real-time applications with critical timing requirements

Performance analysis of TDMA-based Wireless Network for Safety-critical Avionics

The opportunities and challenges for using wireless interconnects for safety-critical avionics have been discussed in our previous work.A Wireless Avionics Network (WAN)has been proposed based on hybrid architecture UWB and Switched Ethernet with adequate reliability and security mechanisms to increase scalability and reduce electromagnetic susceptibility. Furthermore, a TDMA-based protocol was considered to guarantee a contention free access and enhance communication predictability. However, the use of wireless technologies may increase the communication latencies due to transmission errors, and real time constraints have to be verified. In order to deal with the worst case performance analysis of such network, an appropriate schedulability analysis based on Network Calculus formalism is presented in this paper and obtained results for a realistic case study are discussed herein

Study of Obstacle effect on the GPSR protocol and a Novel Intelligent Greedy Routing protocol for VANETs

In recent years, connected vehicle technologies have been developed by automotive companies, academia, and researchers as part of Intelligent Transportation Systems (ITS). This group of stakeholders continue to work on these technologies to make them as reliable and cost-effective as possible. This attention is because of the increasing connected vehicles safety-related, entertainment, and traffic management applications, which have the potential to decrease the number of road accidents, save fuel and time for millions of daily commuters worldwide. Vehicular Ad-Hoc Network (VANET), which is a subgroup of Mobile Ad-Hoc Network (MANET), is being developed and implemented in vehicles as the critical structure for connected vehicles applications. VANET provides a promising concept to reduce the number of fatalities caused by road accidents, to improve traffic efficiency, and to provide infotainment. To support the increasing number of safety-related applications, VANETs are required to perform reliably. Since VANETs promise numerous safety applications requiring time-bound delivery of data packets, it is also necessary to replicate real-world scenarios in simulations as accurately as possible. Taking into account the effect of realistic obstacles while simulating a variety of case scenarios increases the reliability of the tested routing protocol to appropriately perform in real-world situations. It also exposes routing protocols to possible vulnerabilities caused by obstacles. Nevertheless, it is not uncommon for researchers to omit real-world physical layer communication hurdles in simulation-based tests, including not considering the effect of obstacles on their routing protocol performance evaluation simulations. Consequently, the performance of these protocols is usually overestimated and do not support in real-world environment. Failure to account for obstacle effects overstate the network performance. In this thesis, a framework for measuring obstacle effects on routing protocols is defined. We also propose, a new routing protocol based on the traditional Greedy Perimeter Stateless Routing (GPSR) protocol called Intelligent Greedy Routing (IGR) protocol. The proposed IGR protocol considers a parameter called $Receptivity$ to chose the next hop in a route. We implemented the new protocol using the Simulation of Urban Mobility (SUMO) and the Network Simulator (NS-3). An analysis of Packet Delivery Ratio (PDR), End-to-End Delay (E2ED) and Mean Hop count with the assumption that nodes (vehicles) are moving in various topologies is presented in this thesis. The study presented here gives a general idea of the effects of obstacles on the Greedy Perimeter Stateless Routing (GPSR) protocol considering multiple realistic scenarios such as Urban, Residential and Highway. In addition, we compare the performance of GPSR and the new IGR protocols with the presence of obstacles considering various topologies. The new proposed IGR protocol performs better compared to the traditional GPSR for all the investigated metrics

TAURUM P2T: Advanced secure CAN-FD architecture for road vehicle

Interconnected devices are growing very fast in today's automotive market, providing new and complex features that cover very different domains. This vast and continuous requirement for new features brings to impact areas categorized as real-time safety-critical devices, opening the possibility to add potential vulnerabilities. By analyzing the security vulnerabilities within vehicle networks, this paper aims at proposing a new generation of a secure architecture based on Controller Area Network (CAN) called TAURUM P2T. This new architecture looks at mitigating the vulnerabilities found in the current network systems of road vehicles by introducing a low-cost and efficient solution based on the introduction of a Secure CAN network able to implement a novel key provisioning strategy. The proposed architecture has been implemented, resorting to a commercial Multi-Protocol Vehicle Interface module, and the obtained results experimentally demonstrate the approach's feasibility

USING SMART GRID TECHNOLOGY IN ENERGY DISTRIBUTION SYSTEMS

Using smart grid technology in today energy distribution systems will reduce cost, reach manageability, provide safety of energy supply chain to end customer and provide new innovative energy service delivery. Term “smart grid” can be explained with following words – intelligent, self-sustained, with management based on IP (Internet Protocol) telecommunication network for transportation of critical data in real-time from customer site (smart meters, smart homes, smart buildings) and distributed power plants to central management station (energy service provider operations). Main function of the central management station is to acquire and evaluate stored data in real time and based on this stored and evaluated data, in case of emergency, power outage on some subsystem or increased need for power on specific location, to apply necessary steps in real-time. Therefore data conformity and security in smart grid technology is an important function concept to implement. Nevertheless primary goal of smart grid technology is to improve the efficiency, reliability and safety of power delivery by modernizing both the transmission and the distribution grids. This article has a goal to provide a high-end top-level view of a modern telecommunication infrastructure needed to implement a smart grid technology into an energy transmission and distribution grid

Adaptive intelligent middleware architecture for mobile real-time communications

Provision of instantaneous, mobile and dependable communications in military and safety-critical scenarios must overcome certain wireless network issues: lack of reliable existing infrastructure, immutability of mission-critical protocols and detrimental wireless dynamics with contributing factors including hidden transmitters and fading channels. Benchmarked approaches do not fully meet these challenges, due to reliance on addressing Quality of Service (QoS) at a layer-specific level rather than taking a system of systems approach. This paper presents an adaptive middleware methodology to provide timely MANET communications through predictive selection and dynamic contention reduction, without invasive protocol modification. This is done using ROAM, the proposed, novel Real-time Optimised Ad hoc Middleware based architecture. Extensive simulation results demonstrate the adaptability and scalability of the architecture as well as capability to bound maximum delay, jitter and packet loss in complex and dynamic MANETs

Analyzing the vulnerability of wireless sensor networks to a malicious matched protocol attack

Safety critical, Internet of Things (IoT) and space-based applications have recently begun to adopt wireless networks based on commercial off the shelf (COTS) devices and standardized protocols, which inherently establishes the security challenge of malicious intrusions. Malicious intrusions can cause severe consequences if undetected, including, complete denial of services. Particularly, any safety critical application requires all services to operate correctly, as any loss can be detrimental to safety and/or privacy. Therefore, in order for these safety critical services to remain operational and available, any and all intrusions need to be detected and mitigated. Whilst intrusion detection is not a new research area, new vulnerabilities in wireless networks, especially wireless sensor networks (WSNs), can be identified. In this paper, a specific vulnerability of WSNs is explored, termed here the matched protocol attack. This malicious attack uses protocol-specific structures to compromise a network using that protocol. Through attack exploration, this paper provides evidence that traditional spectral techniques are not sufficient to detect an intrusion using this style of attack. Furthermore, a ZigBee cluster head network, which co-exists with ISM band services, consisting of XBee COTS devices is utilized, along with a real time spectrum analyzer, to experimentally evaluate the effect of matched protocol interference on a realistic network model. Results of this evaluation are provided in terms of device errors and spectrum use. This malicious challenge is also examined through Monte-Carlo simulations. A potential detection technique, based on coarse inter-node distance measurements, which can theoretically be used to detect matched protocol interference and localize the origin of the source, is also suggested as a future progression of this work. Insights into how this attack style preys on some of the main security risks of any WSN (interoperability, device limitations and operation in hostile environments) are also provided

Application of MPLS-TP for transporting power system protection data

Power utilities are increasingly dependent on the use of communications networks. These networks are evolving to be packet-based, rather than using conventional Time-Division Multiplexing (TDM) technologies. Transporting current differential protection traffic over a packet network is especially challenging, due to the safety-critical nature of protection, the strict requirements for low delay and low asymmetrical delay, and the extensive use of legacy TDM-based protocols. This paper highlights the key technical characteristics of Multi-Protocol Label Switching-Transport Profile (MPLS-TP), and demonstrates its application for transporting current differential protection traffic. A real-time hardware-in-the-loop testing approach has been used to thoroughly validate the technologies in various configurations. It is demonstrated that MPLS-TP technologies can meet the requirements of current differential protection and other, less critical applications. In particular, it is shown that delay and asymmetrical delay can be controlled through the inherent use of bi-directional paths---even when “hitless” link redundancy is configured. The importance of appropriate traffic engineering, clocking schemes, circuit emulation methods is also demonstrated