Osama M. Hussain Rehman

An adaptive relay nodes selection scheme for multi-hop broadcast in VANETs

Vehicular ad hoc networks (VANETs) have potential applications for improving on-road driving experiences including preemptive road safety measures and provision for infotainment services. This paper proposes a Bi-directional Stable Communication (BDSC) relay nodes selection scheme designed for multi-hop broadcasting protocols over a platoon of vehicles. Relay nodes selection is based on quantitative representation of link qualities for single-hop neighboring nodes by using a proposed link quality estimation algorithm. The BDSC scheme aims to improve packet delivery ratio while maintaining low end-to-end communication delays over a densely populated network with nodes distributed over a large coverage area. To achieve this, the proposed scheme attempts to adaptively balance between the estimated link qualities and the distance between the source broadcaster and the potential forwarders when selecting the next hop nodes for relaying the broadcast messages. Our results from extensive simulation analysis reveal that the proposed BDSC scheme outperforms existing multi-hop broadcasting schemes in terms of packet delivery ratio when evaluated over a densely populated VANETs.

Performance impact of relay cardinality on sender-driven messages dissemination in VANETs

Wireless communication protocols based on vehicular ad hoc networks (VANETs) have potential applications for improving on-road experiences including road safety. This work investigates relay cardinality impact on the performance of sender-driven multi-hop messaging protocols over VANETs. The aim of this study is to identify suitable relay set cardinalities for varying spectrum of applications, with emphasis on active alert messaging protocols. Impact of relay cardinality is evaluated while considering end-to-end communication delays and reachability of messages as performance measurement metrics. Performance evaluation is conducted for broadcast messages over large coverage and densely populated networks. Simulation experiments reveal that reachability of the sender-driven broadcasts improve to a certain extend with increase in relay cardinality, but at the expense of increasing end-to-end delays.

Improving reachability of multi-hop alert messages dissemination in VANETs

Alert messaging protocols based on vehicular ad hoc networks (VANETs) are speculated as promising on-board applications for improving road safety. This work presents a novel alert broadcasting protocol based on estimated link qualities. Link quality estimations are based on the proposed Bi-Directional Stable Communication (BDSC) protocol which aims at achieving high reachability of alert messages. The new protocol makes better selection of relay nodes during multi-hop broadcasts, resulting in reachability improvement of alert messages over a platoon of vehicles. Simulation experiments reveal that in dense traffic scenarios, reachability of the proposed BDSC protocol outperforms the conventional furthest distance based relay selection protocols by more than 20%.

Relay selection for alert messaging in vanets based on bi-directional stable communication approach

Wireless communication alert messaging protocols based on vehicular ad hoc networks (VANETs) have promising role to play in reducing road accidents. Reliable reception of the alert messages to all concerned vehicles within a certain time limit is a prime objective to achieve when employing alert messaging in VANETs. In this work, we propose a bi-directional link quality assessment based alert messaging protocol. Simulated performance evaluation is presented while stressing on reachability of the alert messages in varying network density scenarios. The proposed communication model is compared to conventional distance based alert messaging as being the most widely used technique for relay nodes selection. The proposed protocol outperforms in reachability the conventional one, while adhering well below to delay requirements of alert messages propagation for most endangered vehicles.

Experimental Evaluation of Safety Beacons Dissemination in VANETs

Abstract Efficient beacon delivery and accurate GPS position acquisition are key factors in designing robust safety applications in VANETs. Consequently, minimum delivery delays for beacons and accurate vehicle positional information are crucial parameters to avoid any upcoming emergencies on the road such as vehicle collisions or other hazardous situation. This paper studies the accuracy level of GPS acquired positional information and evaluates the effects of beacon transmission frequency and beacon size on beacon delivery delays by performing experimental field tests on four vehicles. Our experimental results indicate that the GPS acquired position may vary from the actual position of the vehicle, and that the packet size and broadcasting frequency are key factors in achieving high performance for safety applications in VANETs.

Link quality estimation in VANETs for multi-hop alert messages dissemination

Reception of alert messages by endangered vehicles at time of an emergency event e.g., a traffic accident is a prime objective of alert messaging protocols in vehicular ad hoc networks VANETs. This work proposes a new bi-directional stable communication BDSC protocol for relay nodes selection in multi-hop alert messages propagation in VANETs. The BDSC protocol is based on a dynamic link quality estimation algorithm. The proposed protocol is evaluated by assessing the alert messages reachability in varying network size and traffic densities. Results obtained from extensive simulation experiments favour the performance of the proposed protocol with a large margin of reachability improvement compared to conventional furthest distance relay selection protocols. In a multi-lane road segment with dense traffic scenario, reachability improvement of approximately 25% is noticed over the furthest distance protocols. This reachability improvement is achieved with comparable end-to-end communication delays to those exhibited by furthest distance-based solutions.

Economics of Cyber Security and the Way Forward

Initiatives carried by companies, institutes and governments to flourish and embellish the Information and Communication Technology ICT among the public have led to its penetration into every walk of life. ICT enhances the efficiency of various systems, such as the organisation and transfer of data. However, with the digital and remote access features of ICT comes the motivation towards financial, political and military gains by rivals. Security threats and vulnerabilities in existing ICT systems have resulted in cyber-attacks that are usually followed by substantial financial losses. This study discusses the security in ICT from a business, economic and government perspective. The study makes an attempt to understand the seriousness of the security issues and highlights the consequences of security breech from an economic perspective. Based on the performed analysis, the factors behind these attacks are provided along with recommendations for better preparations against them.

Hybrid Relaying for Multi-Hop Broadcast in VANETs

Multi-hop message broadcast is considered as the primary mode of communication for many applications in vehicular ad-hoc networks (VANETs). Reliable and timely reception of the disseminated messages are important requirements for multi-hop messaging schemes in vehicular networks, especially for critical-in-nature safety alert messages. This work proposes a sender- oriented hybrid relay nodes selection scheme for multi-hop broadcasting in VANETs. The hybrid scheme exploits the spatial diversity of the potential nodes from the sender. The proposed scheme aims to improve messages reachability over high node density networks while attaining low end-to-end delays and high saved rebroadcasts. Simulation results shows that the proposed hybrid scheme outperforms existing solutions in terms of messages reachability at marginal costs in end-to- end delays and saved rebroadcasts.