Md. Abdul Hamid

Design of a QoS-Aware Routing Mechanism for Wireless Multimedia Sensor Networks

In wireless sensor networks, majority of routing protocols considered energy efficiency as the main objective and assumed data traffic with unconstrained delivery requirements. However, the introduction of image and video sensors demands certain quality of service (QoS) from the routing protocols and underlying networks. Managing real-time data requires both energy efficiency and QoS assurance in order to ensure efficient usage of sensor resources and correctness of the collected information. In this paper, we present a novel QoS-aware routing protocol to support high data rate for wireless multimedia sensor networks. Being multi-channel multi-path the foundation, the routing decision is made according to the dynamic adjustment of the required bandwidth and path-length-based proportional delay differentiation for real-time data. The proposed protocol works in a distributed manner to ensure bandwidth and end- to-end delay requirements of real-time data. At the same time, the throughput of non-real-time data is maximized by adjusting the service rate of real-time and non-real-time data. Results evaluated in simulation demonstrate a significant performance improvement in terms of average delay, average lifetime and network throughput.

SHWMP: a secure hybrid wireless mesh protocol for IEEE 802.11s wireless mesh networks

In recent years, mesh networking has emerged as a key technology for the last mile Internet access and found to be an important area of research and deployment. The current draft standard of IEEE 802.11s has defined routing for Wireless Mesh Networks (WMNs) in layer-2 and is termed as Hybrid Wireless Mesh Protocol (HWMP). However, security in routing or forwarding functionality is not specified in the standard. As a consequence, HWMP in its current from is vulnerable to various types of routing attacks such as flooding, route disruption and diversion, spoofing etc. In this paper, we propose SHWMP, a secure HWMP protocol for WMN. The proposed protocol uses cryptographic extensions to provide authenticity and integrity of HWMP routing messages and prevents unauthorized manipulation of mutable fields in the routing information elements. We show via analysis that the proposed SHWMP successfully thwarts all the identified attacks. Through extensive ns-2 simulations, we show that SHWMP provides higher packet delivery ratio with little increase in end-to-end delay, path acquisition delay and control byte overhead.

Thermal-Aware Multiconstrained Intrabody QoS Routing for Wireless Body Area Networks

Wireless body area networks (WBANs) can be formed including implanted biosensors for health monitoring and diagnostic purposes. However, implanted biosensors could cause thermal damages on human tissue as it exhibits temperature rise due to wireless communication and processing tasks inside the human body. Again, Quality of Service (QoS) provisioning with multiconstraints (delay and reliability) is a striking requirement for diverse application types in WBANs to meet their objectives. This paper proposes TMQoS, a thermal-aware multiconstrained intrabody QoS routing protocol for WBANs, with the aim of ensuring the desired multiconstrained QoS demands of diverse applications along with keeping the temperature of the nodes to an acceptable level preventing thermal damages. We develop a cross-layer proactive routing framework that constructs an ongoing routing table which includes multiple shortest-path routes to address diverse QoS requirements. To avoid the packets to traverse through heated areas known as hotspot, we devise a hotspot avoidance mechanism. The route selection algorithm of TMQoS selects forwarder(s) based on the intended QoS demands of diverse traffic classes. The performance of TMQoS has been evaluated through simulation which demonstrates that the protocol achieves desired QoS demands while maintaining low temperature in the network compared to the state-of-the-art thermal-aware approaches.

A Secure Hybrid Wireless Mesh Protocol for 802.11s Mesh Network

Wireless Mesh Network (WMN) has emerged as a key technology and found a great deal of interest for the researchers in the recent past. Hybrid Wireless Mesh Protocol (HWMP) is the default path selection (i.e., routing) protocol fully specified in the current draft D.1.06 of 802.11s for WMN. However, security in routing or forwarding functionality is not specified in the standard. As a consequence, HWMP in its current from is vulnerable to various types of routing attacks. In this paper, we propose a secure version of HWMP (SHWMP) that operates similarly to that of HWMP but uses cryptographic extensions to provide authenticity and integrity of routing messages and prevents unauthorized manipulation of mutable fields in the routing information elements. We have shown through analyses and simulation that SHWMP is robust against identified attacks and provides higher packet delivery ratio and incurs little computational and storage overhead to ensure security.

A Schedule-based Multi-channel MAC Protocol for Wireless Sensor Networks

Due to the half-duplex property of the sensor radio and the broadcast nature of wireless medium, limited bandwidth remains a pressing issue for wireless sensor networks (WSNs). The design of multi-channel MAC protocols has attracted the interest of many researchers as a cost effective solution to meet the higher bandwidth demand for the limited bandwidth in WSN. In this paper, we present a scheduled-based multi-channel MAC protocol to improve network performance. In our protocol, each receiving node selects (schedules) some timeslot(s), in which it may receive data from the intending sender(s). The timeslot selection is done in a conflict free manner, where a node avoids the slots that are already selected by others in its interference range. To minimize the conflicts during timeslot selection, we propose a unique solution by splitting the neighboring nodes into different groups, where nodes of a group may select the slots allocated to that group only. We demonstrate the effectiveness of our approach thorough simulations in terms of performance parameters such as aggregate throughput, packet delivery ratio, end-to-end delay, and energy consumption.

EFT: a high throughput routing metric for IEEE 802.11s wireless mesh networks

In this paper, we present a throughput-maximizing routing metric, referred to as expected forwarding time (EFT), for IEEE 802.11s-based wireless mesh networks. Our study reveals that most of the existing routing metrics select the paths with minimum aggregate transmission time of a packet. However, we show by analyses that, due to the shared nature of the wireless medium, other factors, such as transmission time of the contending nodes and their densities and loads, also affect the performance of routing metrics. We therefore first identify the factors that hinder the forwarding time of a packet. Furthermore, we add a new dimension to our metric by introducing traffic priority into our routing metric design, which, to the best of our knowledge, is completely unaddressed by existing studies. We also show how EFT can be incorporated into the hybrid wireless mesh protocol (HWMP), the path selection protocol used in the IEEE 802.11s draft standard. Finally, we study the performance of EFT through simulations under different network scenarios. Simulation results show that EFT outperforms other routing metrics in terms of average network throughput, end-to-end delay, and packet loss rate.

Fair data collection in wireless sensor networks: analysis and protocol

In general, wireless sensor networks (WSNs) consist of many sensors which transmit data to a central node, called the sink, possibly over multiple hops. This many-to-one data routing paradigm leads to nonuniform traffic distribution for the different sensors (e.g., nodes closer to the sink transfer more traffic than those farther away). In this paper, we perform an analysis of the fairness issue by presenting a tree-based WSN and derive the throughput, delay, and energy distribution for each sensor under the fairness constraint. Based on the analysis, we design our fair data collection protocol in which each node decides its media access and packet forwarding strategies in a distributed manner. Finally, we demonstrate the effectiveness of our solution through simulations. The results for the proposed protocol show the accuracy of the analysis and show that the protocol ensures the fair delivery of packets and reduces end-to-end delay. Based on the analysis, we also quantitatively determine the energy required for each of the nodes and show that a nonuniform energy distribution can maximize the network lifetime for the WSN scenario under study.

QoS and trust-aware coalition formation game in data-intensive cloud federations

This paper addresses the problem of efficient federation formation by the cloud providers (CPs) with an aim to fulfill the dynamic resource demands of users for supporting data‐intensive workloads. Existing works only focus on forming federations based on the highest profit gained by each of the CPs in a federation. Therefore, these approaches often suffer from the risk of selecting unreliable CPs in the federation resulting in additional penalty cost and loss of CPss reputation due to service level agreement violation between the users and the federation. In contrast, we argue that a trust model is necessary to find the most promising cloud collaborators. Accordingly, we propose a novel cloud federation formation mechanism by utilizing a trust‐based cooperative game theory, which enables the CPs to dynamically form a federation based on profit maximization and penalty cost minimization as a result of selecting the trustworthy CPs. Simulation results show that the cloud federation formed by the proposed mechanism is stable, satisfies the fairness property, and yields higher profit for the participating CPs in the long run without incurring penalty cost as compared with the state‐of‐the‐art approaches. Copyright

A robust security scheme for wireless mesh enterprise networks

In this paper, we address the security challenges for wireless mesh enterprise networks (WMENs). The topology and communication characteristics of WMEN include the following: (a) deployment of the network devices are not planar, rather, devices are deployed over three-dimensional space (e.g., office buildings, shopping malls, grocery stores, etc.); (b) messages, generated/received by a mesh client, traverse through mesh routers in a multihop fashion; and (c) mesh clients, being mostly mobile in nature, may result in misbehaving or be spurious during communications. We propose a security scheme for WMEN in order to ensure that only authorized users are granted network access. Particularly, our scheme includes: (a) a deterministic key distribution technique that perfectly suits the network topology, (b) an efficient session key establishment protocol to achieve the client–router and router–router communications security, and (c) a distributed detection mechanism to identify malicious clients in the network. Analytical and simulation results are presented to verify our proposed solutions.

Developing Security Solutions for Wireless Mesh Enterprise Networks

Our study on the deployment topology and communication characteristics of wireless mesh enterprise networks (WMENs) leads to three critical security challenges: (a) deployment of network devices are not planar, rather devices are deployed over three-dimensional space, (b) message generated/received by a mesh client traverses through mesh routers in a multi-hop fashion, and (c) mesh clients being mostly mobile in nature may result in misbehaving or spurious during communications. We address these challenges for WMENs that may be a small network within an office or a medium-size network for all offices in an entire building, or a large scale network among offices in multiple buildings. We develop a matrix key distribution technique that perfectly suits the network topology. A session key establishment protocol is presented to achieve the client-router and router-router communication security. Finally, a misbehaving client detection algorithm is developed based on the communication history. We analyze and evaluate the performance to show the suitability of our proposed security solutions.