Adnan Shahid Khan

Voronoi cell geometry based dynamic Fractional Frequency Reuse for OFDMA cellular networks

Interference Management (IM) is one of the major challenges of next generation wireless communication. Fractional Frequency Reuse (FFR) has been acknowledged as an efficient IM technique, which offers significant capacity enhancement and improve cell edge coverage with low complexity. In literature, FFR has been analyzed mostly with cellular networks described by Hexagon Grid Model, which is neither tractable nor scalable to the dense deployment of next generation wireless networks. Moreover, the perfect geometry based grid model tends to overestimate the system performance and not able to reflect the reality. In this paper, we use the stochastic geometry approach, FFR is analyzed with cellular network modeled by homogeneous Poisson Point Process (PPP). A dynamic frequency allocation scheme is proposed which take into account the randomness of the cell coverage area describe by Voronoi tessellation. It is shown that the proposed scheme outperforms the traditional fixed frequency allocation schemes in terms of per user capacity and capacity density.

Resource allocation for uplink M2M communication: A game theory approach

Machine-to-Machine (M2M) communication in cellular network is the driver for the future Internet of Things (IoT). The main challenge of M2M communication is the possibility of huge traffic in the uplink network that can cause problem in the network. This paper considers the problem of resource allocation among machines connecting in uplink to different femto base stations (FBSs). Resource allocation problem is analyzed through both non-cooperative and cooperative game to maximize their data rate and minimize utilization of power. Numerical result shows that by adapting non-cooperative game, all machines are getting data rate as per Nash Equilibrium (NE) or either they can set their strategy to maximize their data rate selfishly. On the other hand for coalitional game theory approach machines who participate in game are getting fair resource allocations.

Lightweight distributed geographical: a lightweight distributed protocol for virtual clustering in geographical forwarding cognitive radio sensor networks

Recent literature characterizes future wireless sensor networks WSN with dynamic spectrum capabilities. When cognitive radio is introduced as a main component of a network, a network management protocol is needed to ensure network connectivity and stability especially in highly dynamic environments. Implementing such protocols in WSN opens more challenges because of the resource constraints in sensor networks. We propose a distributed lightweight solution that fulfills this need for WSN. With this protocol, a node in a multichannel environment is quickly able to establish a control channel with neighboring nodes. Lightweight distributed geographical either increases or reduces the coverage area of the control channel based on perceived interference and adequately takes care of intersecting nodes with minimal overhead. By identifying local minima nodes, it also has the potentiality of reducing route failure by 70% further reducing the time and energy overhead incurred by switching to angle routing or maximum power transmission schemes usually used to solve the local minima issue. The work shows best operating values in terms of duty cycle and signal to noise ratio threshold frequencies and the lightweight nature of lightweight distributed geographical in terms of energy and communication overhead, which suits network management protocols for cognitive radio sensor networks. Copyright

An improved authentication key management scheme for Multihop relay in IEEE 802.16m networks

IEEE 802.16m Multihop relay network is assiduously developing to accomplish high capacity services with large cell coverage. However due to lack of physical boundaries and injection of distributed relays, it is known to be more vulnerable to security holes as a trade off. In this paper we propose a new distributed authentication key scheme for Multihop Relays IEEE 802.16m network service. The propose scheme uses decode and forward relays with localized authentication. The scheme works in distributed authentication to authenticate Subscriber station (SS) and Relay stations (RS) at initial network entry. Our new imprpoved distributed scheme utilizes healthy security issues and the Multihop Relay network application features. Both analysis and performance evaluation shows that our scheme can significantly increases the network throughput and reduce the security holes as well as communication overheads.

A Review of Vehicle to Vehicle Communication Protocols for VANETs in the Urban Environment

Vehicular Ad-hoc Networks (VANETs) have been gaining significant attention from the research community due to their increasing importance for building an intelligent transportation system. The characteristics of VANETs, such as high mobility, network partitioning, intermittent connectivity and obstacles in city environments, make routing a challenging task. Due to these characteristics of VANETs, the performance of a routing protocol is degraded. The position-based routing is considered to be the most significant approach in VANETs. In this paper, we present a brief review of most significant position based unicast routing protocols designed for vehicle to vehicle communications in the urban environment. We provide them with their working features for exchanging information between vehicular nodes. We describe their pros and cons. This study also provides a comparison of the vehicle to vehicle communication based routing protocols. The comparative study is based on some significant factors such as mobility, traffic density, forwarding techniques and method of junction selection mechanism, and strategy used to handle a local optimum situation. It also provides the simulation based study of existing dynamic junction selection routing protocols and a static junction selection routing protocol. It provides a profound insight into the routing techniques suggested in this area and the most valuable solutions to advance VANETs. More importantly, it can be used as a source of references to other researchers in finding literature that is relevant to routing in VANETs.

Towards vulnerability prevention model for web browser using interceptor approach

Cross Site Scripting (XSS) is popular security vulnerability in modern web applications. XSS attacks are malicious scripts which are embedded by attackers into the source code of web page to be executed at client side by browsers. Researchers have proposed many techniques for detection and prevention of XSS, but eliminating XSS still remains a challenge. In this paper the authors propose a web security model for XSS vulnerability prevention for web browsers using interceptor approach. Several client and server side solution have been proposed but they degrade the browsing performance and increases configuration overheads. The proposed model is an effective solution with minimal performance overheads using both Client and Server side location in detection and prevention of XSS.

Defending Malicious Script Attacks Using Machine Learning Classifiers

The web application has become a primary target for cyber criminals by injecting malware especially JavaScript to perform malicious activities for impersonation. Thus, it becomes an imperative to detect such malicious code in real time before any malicious activity is performed. This study proposes an efficient method of detecting previously unknown malicious java scripts using an interceptor at the client side by classifying the key features of the malicious code. Feature subset was obtained by using wrapper method for dimensionality reduction. Supervised machine learning classifiers were used on the dataset for achieving high accuracy. Experimental results show that our method can efficiently classify malicious code from benign code with promising results.

A Dynamic Energy Savvy Routing Algorithm for Mobile Ad-Hoc and Sensor Networks

Mobile Ad-hoc and Sensor Networks (MASNETs) are energy constrained networks which have been the focus of many recent research and development efforts. In MASNETs, the network topologies are frequently change due to the moving sensor nodes that have low radio frequency coverage which make the design and implementation of a routing protocol in this networks very challenging. Thus, the Dynamic Energy Savvy (DES-AODV) routing algorithm is proposed to enhance the performance of Ad-hoc On Demand Distance Vector (AODV) by changing the routing metric from hop count to estimated distance that is based on the Received Signal Strength Indicator (RSSI) values. The performance of DES-AODV is evaluated and compared with the existing AODV in terms of the average percentage of packet loss and energy consumption with the density of mobile nodes. The simulation results show that the proposed DES-AODV outperforms the existing AODV in both percentage of packet loss and energy consumption.

Neighbor Selection Protocol for Heterogeneous Information Dissemination in Opportunistic Networks

In Opportunistic Networks, information forwarding takes place when nodes are in communication range. Absence of knowledge on network topology prior information forwarding poses a compelling challenge in Opportunistic Networks. In these networks, disconnected mobile peers use mobility to opportunistically and dynamically connect to each other in order to disseminate heterogeneous information towards the intended destination. Flooding disseminates information to all nodes in range. Hence, it achieves high delivery performance. However, this form of dissemination congests the network and create considerable amount of network overheads. In this paper, a social-based neighbor selection protocol is proposed to enhance the heterogeneous information dissemination through peer-to-peer interaction in Opportunistic Networks. Neighbor is selected based on social structure formulated by Frequency in Range, Frequency of Interaction metrics and Heterogeneity of information. A high valued metric peer from the list of candidate peers is selected as potential forwarder to disseminate information. The delivery performance impact of our protocol on information dissemination was investigated and has been analyzed in customized simulation tool. Experimental results showed that, the proposed neighbor selection protocol achieved delivery performance close to random selection in flooding and reduced 88.25% push overhead incurred during dissemination.

Identify the best location to place data based on social interaction in opportunistic network

Opportunistic networking is an evolution of Ad hoc mobile communication paradigm. Sharing information in opportunistic networks is challenging due to intermittent connectivity, short connection durations and a highly dynamic topology. Numbers of researches have proposed data dissemination approach to increase the chances of delivering information to the destination node with the minimum duration of time. This paper presents the mechanism of identifying the best location based on social interaction to increasing the data dissemination successful rate in opportunistic network. From the simulation results, we found that in the high density population, placing data based on identified location increases the data exchange between nodes about 38% compared to random data placement. Therefore placing data in the right place contribute the effective of data dissemination among mobile nodes.