Yousaf Bin Zikria

A survey on routing protocols supported by the Contiki Internet of things operating system

Abstract Standardization and technology advancements have helped the realization of the Internet of things (IoT). The availability of low-cost IoT devices has also played a key role in furthering IoT research, development, and deployment. IoT operating systems (OSs) provide integration of software and hardware components. The availability of standard protocols, heterogeneous hardware support, ease of development, and simulation or emulation support are desirable features of IoT OSs. Contiki OS is one of the contenders for future IoT OSs. It was proposed in 2003, and since then, it has been continually under development and upgraded by professionals, academia, and researchers. Contiki OS supports open source, Internet standards, power awareness, dynamic module loading, and many hardware platforms. The diverse applications of IoT, including smart homes, smart health, smart cities, require efficient network connectivity and demand intelligent routing protocols that can handle heterogeneous, mobile, and diverse networks. Subsequently, designing routing protocols for memory- and central processing unit (CPU)-constrained IoT devices is a very challenging task. Therefore, this paper surveys the state-of-the-art routing protocols of Contiki OS. To the best of the authors’ knowledge, this is the first study to classify the Contiki OS routing protocol literature and list the potential challenges and future work.

Trust Mechanisms to Secure Routing in Wireless Sensor Networks: Current State of the Research and Open Research Issues

Routing is one of the most important operations in wireless sensor networks (WSNs) as it deals with data delivery to base stations. Routing attacks can cripple it easily and degrade the operation of WSNs significantly. Traditional security mechanisms such as cryptography and authentication alone cannot cope with some of the routing attacks as they come from compromised nodes mostly. Recently, trust mechanism is introduced to enhance security and improve cooperation among nodes. In routing, trust mechanism avoids/includes nodes in routing operation based on the estimated trust value. Many trust-based routing protocols are proposed to secure routing, in which they consider different routing attacks. In this research work, our goal is to explore the current research state and identify open research issues by surveying proposed schemes. To achieve our goal we extensively analyze and discuss proposed schemes based on the proposed framework. Moreover, we evaluate proposed schemes based on two important factors, which are energy consumption and attack resiliency. We discuss and present open research issues in the proposed schemes and research field.

Opportunistic Hybrid Transport Protocol (OHTP) for Cognitive Radio Ad Hoc Sensor Networks

The inefficient assignment of spectrum for different communications purposes, plus technology enhancements and ever-increasing usage of wireless technology is causing spectrum scarcity. To address this issue, one of the proposed solutions in the literature is to access the spectrum dynamically or opportunistically. Therefore, the concept of cognitive radio appeared, which opens up a new research paradigm. There is extensive research on the physical, medium access control and network layers. The impact of the transport layer on the performance of cognitive radio ad hoc sensor networks is still unknown/unexplored. The Internet’s de facto transport protocol is not well suited to wireless networks because of its congestion control mechanism. We propose an opportunistic hybrid transport protocol for cognitive radio ad hoc sensor networks. We developed a new congestion control mechanism to differentiate true congestion from interruption loss. After such detection and differentiation, we propose methods to handle them opportunistically. There are several benefits to window- and rate-based protocols. To exploit the benefits of both in order to enhance overall system performance, we propose a hybrid transport protocol. We empirically calculate the optimal threshold value to switch between window- and rate-based mechanisms. We then compare our proposed transport protocol to Transmission Control Protocol (TCP)-friendly rate control, TCP-friendly rate control for cognitive radio, and TCP-friendly window-based control. We ran an extensive set of simulations in Network Simulator 2. The results indicate that the proposed transport protocol performs better than all the others.

LTE in the Unlicensed Spectrum: A Survey

ABSTRACT Fueled by the increasing popularity of handheld mobile devices with powerful data processing capabilities, the wireless industry is witnessing an avalanche of mobile traffic. This unprecedented escalation has imposed significant challenges due to the limited licensed spectrum for cellular networks. Any effort to achieve capacity growth through network densification will face the challenge of severe inter-cell interference. Among the most effective solutions to this issue is to make the best use of all spectrum types through matured technology. Long-term evolution (LTE) access to unlicensed spectrum is considered one of the latest groundbreaking innovations to provide high-performance and a seamless user experience under a unified radio technology by extending LTE to the readily available unlicensed spectrum. In this article, we introduce the dawn of LTE access to unlicensed spectrum as a boon to the spectrum scarcity problem. Then, we explore deployment scenarios for LTE in unlicensed spectrum. We further identify key issues in bringing LTE unlicensed spectrum access to reality, together with other technologies for accessing unlicensed spectrum, specifically Wi-Fi. Finally, we discuss some existing coexistence mechanisms for successful, harmonious deployment of LTE and Wi-Fi in the same unlicensed band.

Heuristic Approach to Select Opportunistic Routing Forwarders (HASORF) to Enhance Throughput for Wireless Sensor Networks

Biological schemes provide useful resources for designing adaptive routing protocols for wireless sensor networks (WSNs). The key idea behind using bioinspired routing is to find the optimal path to the destination. Similarly, the idea of opportunistic routing (OR) is to find the least number of hops to deliver the data to the destination. Numerous routing schemes have been proposed in WSNs while targeting various performance goals, such as throughput, delay, and link quality. Recently, OR schemes have come onto the scene in comparison with the traditional routing algorithms. The performance of OR schemes, however, highly depends on the selection of forwarder nodes. In this paper, we consider a chain network topology, where nodes are separated by an equal distance. The throughput of the chain network is analyzed mathematically, and based on the analysis results, a heuristic algorithm is proposed to choose the forwarder nodes. We evaluate the performance of the proposed Heuristic Approach to Select Opportunistic Routing Forwarders (HASORF) by using the ns-2 simulator and compare it with previous schemes, such as random routing, Extremely Opportunistic Routing (ExOR), and Simple Opportunistic Adaptive Routing (SOAR). The empirical results show that our proposed scheme achieves the best performance among them.

Internet of Things (IoT): Operating System, Applications and Protocols Design, and Validation Techniques

Abstract By combining energy efficient micro-controllers, low-power radio transceivers, and sensors as well as actuators in so called smart objects, we are able to connect the digital cyber world with the physical world as in cyber physical systems. In the vision of the Internet of Things, these smart objects should be seamlessly integrated into the traditional Internet. Typically, smart objects are heavily constrained in terms of computation, memory and energy resources. Furthermore, the commonly used wireless links among smart objects or towards the Internet are typically slow and subject to high packet loss. Such characteristics pose challenges, on one hand in terms of software running on smart objects, and on the other hand in terms of network protocols which smart objects use to communicate. New operating systems, application programming interfaces, frameworks, and middleware have to be designed with consideration of such constraints. In consequence, novel validation methods and experimental tools are needed to study smart object networks in vivo, new software platforms are needed to efficiently operate smart objects, and innovative networking paradigms and protocols are required to interconnect smart objects.

A review of wireless access vehicular environment multichannel operational medium access control protocols: Quality-of-service analysis and other related issues

In recent years, the increase in vehicular traffic has led to a drastic increase in road accidents, thus requiring adequate vehicle safety measures. The intelligent transportation system is a branch of modern technology responsible for delivering such road safety services. The wireless access vehicular environment standard defines how these intelligent transportation system applications can be incorporated in highly varying vehicular ad hoc network environments. Wireless access vehicular environment comprises the IEEE 802.11p and IEEE 1609.4 standards responsible for handling medium access control and transmission mechanisms in vehicular ad hoc networks. However, these standards still face medium access control and physical layer challenges, which must be addressed for reliable quality of service. Several research studies have been proposed and are still underway into improving medium access control protocols in the wireless access vehicular environment stack model defined by IEEE 1609.4 multichannel operation. These proposed medium access control protocols refine the quality of service and reliability of certain performance parameters and have also added some limitations. The working of such wireless access vehicular environment medium access control protocols can be enhanced by defining their limitations and improving them, without causing any performance tradeoffs. Finally, this article works toward reviewing and analyzing such limitations and tradeoffs to provide insight into possible improvements for future medium access control research deployments.

Quality of service analysis for multimedia traffic using DSR, AODV and TORA over Wi-Media ultra wide band

The introduction of new technologies to meet the growing demands of multimedia traffic is on the rise. To cope with this challenge, efficient mechanism is required on all TCP/IP layers. Therefore, this paper studies the performance of routing protocols over Wi-Media ultra-wideband (UWB). The objective of this study is to determine which routing protocol can better meet the quality of service (QoS) for multimedia traffic. The comparison made among three protocols, namely dynamic source routing (DSR), ad hoc on-demand distance vector (AODV), and temporally-ordered routing algorithm (TORA), respectively. The extensive set of simulations has been carried out for video streaming. The metrics used to evaluate the routing protocols are packet loss, throughput, average end-to-end delay, average jitter, and routing overhead. Simulation results and their analysis show that, when there is single source DSR routing protocol perform better QoS for video traffic in terms of higher throughput, the slighter average end-to-end delay, smaller jitter, and less routing overhead. However, in case of multicasting, AODV protocol proves to be the best choice..

An analytical approach to opportunistic transmission under Rayleigh fading channels

In cognitive radio sensor networks, the routing methods including multiple relays have been extensively studied to achieve higher throughput and lower end-to-end delay. As one of innovative approaches, the opportunistic routing scheme was proposed. In this paper, the effectiveness of the opportunistic transmission in terms of reliability and delay of transmission is verified with an analytical way. For the analysis, we establish the probabilistic model with respect to distance and the number of relay nodes under the Rayleigh fading channels including path loss effects. Under this model, we develop a generic Markov chain model to obtain the analytical results and verify the effectiveness of the statistical analysis. The results show that an opportunistic transmission approach is better than traditional multihop transmissions in terms of successful data delivery with fewer transmissions. Consequently, it can provide an energy efficient transmission mechanism for cognitive radio sensor networks.

LTE or LAA: Choosing Network Mode for My Mobile Phone in 5G Network

Long Term Evolution (LTE) in unlicensed spectrum, Licensed Assisted Access (LAA), has been considered as an effective complement in offloading growing traffic. The LAA is expected to be deployed initially through the small cell integrated under LTE macro cell. Therefore, LTE users under the coverage of LAA small cell must decide to connect one of the co-located networks either LTE or LAA to maximize their performance. In this scenario, we model a network selection game for LTE users using mixed strategy game theoretic approach. Afterwards, we formulate behavior of strategic users toward network selection as a function of the number of nearby users. The simulation results show that increasing number of nearby users make a user less likely to switch to LAA small cell. Additionally, more users nearby make it less likely that LAA resources is being utilized.