Monika Rathod

Telework and psychological distance: the mediating effects of culture and technology in four countries

Telework is a phenomenon of growing international importance. U.S.-based studies have raised a concern that telework may increase workers’ psychological distance from the organization and their Workgroup. This study investigates this proposition. It also explore possible mediating effects of technology infrastructure and national culture on the psychological distancing of the workforce as a result of telework. Survey respondents for this study were drawn from four countries: the U.S., Kenya, U.A.E, and India. Dimensions of psychological distance studied were interdependence, cohesiveness, trust, and involvement. Contrary to the expectations formulated in this paper, physical distance induced by telework was not found to contribute to perceived psychological distance. Technological infrastructure was found to have a negative impact on cohesiveness. Cultural uncertainty avoidance was found to result in lower interdependence and trust levels. High power-distance resulted in lower interdependence levels, and high individualism was found to result in lower cohesiveness levels among teleworkers. Thus, culture and technology infrastructure.

Statistical broadcast protocol design with WiBDAT: Wireless Broadcast design and analysis tool

Multi-hop broadcast routing is a critical component in ad-hoc wireless networks. Vehicular ad-hoc network (VANET) applications for example use broadcast communications extensively. Efficient broadcast protocols are required to enable these applications. Multi-hop broadcast algorithms can roughly be classified as either topological or statistical. Statistical protocols are well-suited to applications such as VANET, because they are tolerant of rapid changes in network topology and can be designed to accommodate transmission failures due to fading and collisions. However, unlike topological protocols, statistical methods are highly stochastic in nature so it is not possible to analytically prove these algorithms will connect all nodes in the network. Instead, designers attempt to measure and minimize the probability nodes will not receive a broadcast message. Thus simulation plays an important role in the design and validation of these protocols. The key design factor in statistical protocols is the rebroadcast decision threshold curve. There are no analytical tools for creating these threshold curves, so like many stochastic systems, simulation models are required to develop them. Empirically discovering good threshold curves using simulation models requires many simulation iterations, and thus can be extremely time consuming if these iterations are slow. As a solution, this work introduces the Wireless Broadcast Design and Analysis Tool (WiBDAT), a fast and scalable high-level network simulator built from the ground up specifically for wireless broadcast. WiBDAT provides tools for quickly designing efficient statistical broadcasting protocols and evaluating their performance at a high level. WiBDAT is easy to use and extend, implements a wide variety of broadcast protocols, and provides clear results including innovative visualizations of node and transmit densities.

The PEV security challenges to the smart grid: Analysis of threats and mitigation strategies

Amid growing concern over both the skyrocketing price of fossil fuels and the considerable harm to the environment that is now universally attributed to their use, the gas-powered vehicle is increasingly being viewed as an undesirable means of modern transportation, and the Plug-In Electric Vehicle (PEV) is now being actively developed as its potential replacement. The PEV is powered entirely by electricity, which it acquires by plugging into available electric charging facilities. Concurrently, the electrical grid as we know it is being transformed into a smart grid, which couples physical electrical power generation, transmission, distribution and delivery with an advanced communication network infrastructure that enables provision of several new types of services associated with electrical power management and delivery. The new Smart Grid is seen as an ideal environment for the rapid adoption of the PEV as the primary means of transportation, but such a development poses several threats to the security of the Smart Grid, which could lead to local facilities failure, grid overload, grid instability, and exhaustion of national reserve electrical supply. In this paper we analyze these PEV-induced threats and survey and propose effective mitigation strategies which could be employed to nullify their effectiveness in disrupting the services offered by the Smart Grid.

A hybrid data dissemination scheme for VANETs

Data dissemination in Vehicular Ad hoc NETworks (VANETs) is a key research area with applications that range from traffic flow information to weather reports and related information. Delivering this data with maximum efficiency to a wide area is the focus of research in data dissemination protocols. Data propagation methods preferred for these specialized ad hoc networks fall under two mutually exclusive categories namely store-and-forward and multi-hop broadcasts. Neither of these two categories is noticeably superior and each has its strengths and weaknesses which we outline in this paper. We propose a novel hybrid data dissemination scheme that capitalizes on the strengths of both these categories and mitigates the weaknesses by combining store-and-forward and multi-hop broadcasts. We simulate the proposed hybrid scheme on the JiST/SWANS simulator and evaluate its behavior and performance against pure store-and-forward and pure multi-hop broadcasts by varying the aggregation ratio, number of nodes, and broadcast zone radius.

VANET-based privacy preserving scheme for detecting traffic congestion

We propose a VA NET-based (Vehicular Ad hoc NETwork), privacy-preserving, distributed, collaborative traffic congestion detection and dissemination system that conserves bandwidth and provides drivers with real-time information on traffic congestions over long distances. The system uses vehicles equipped with simple inexpensive devices, as gatherers and distributors of information without the need for costly road infrastructure such as sensors, cameras or external communication equipment. Each vehicle is assumed to be equipped with a Global Positioning System (GPS) device that provides with vehicles current location, a real-time clock and a wireless communication device such as a two-way radio that allows it to communicate with vehicles nearby. The vehicles broadcast their current location, speed and direction at fixed time intervals. Our simulation results show that our solution addresses location privacy concerns and uses aggregation in the form of congestion sections to reduce bandwidth consumption.

Adapting the hybrid data dissemination protocol to density by dynamically controlling the broadcast zone radius

Environment densities change both frequently and rapidly in VANETs. In this paper, we enhance our protocol to become adaptable to density such that as a car moves from one environment density to another, the protocol dynamically sets the broadcast zone radius to adjust to the new density. We study the effect of network density against a range of broadcast zone radius values and obtain a weighted performance metric for each combination. Using this data, we identify the optimal broadcast zone radius per density. We plot these optimal values against the densities values (lambda) known to each of the nodes in the network to obtain the formula we use to determine the broadcast zone radius.

Rapid prototyping of cooperative caching in a VANET: A case study

Due to the complex nature of mobile ad hoc networks, simulation is an important tool used to explore approaches and validate research. De facto simulation tools for networking research such as ns-3 are extremely powerful. However, the time to develop, execute, and analyze a meaningful simulation in these tools can be significant. In addition to the unavoidable learning curve associated with the tool itself, the developer must have significant coding skills and domain knowledge. Once development of the simulation is complete, the time required to execute the simulation can be significant. In this paper, we present a case study that focuses on the use of the Netlogo tool to explore the impact of certain parameters on a cooperative cache deployed within a vehicular network. The results of the Netlogo simulation are then compared to the results of a similar simulation developed in ns-3. Our work shows that meaningful results can be obtained using Netlogo with less investment of time at the expense of flexibility and realism when compared to ns-3. With this approach, if the results of the Netlogo based simulation look promising, a greater investment in a more powerful and accurate simulation using ns-3 can be made. Utilizing this process saves the developer time by focusing on those approaches that look promising.

Investigation of RFID based localization for SmartDrive vehicular network testbed

With emphasis on Smart Cities as the future of our world, Vehicular Communication technology rises to the forefront of our focus to enable efficient and intelligent transportation systems. Vehicular communication relies on localization for various applications such as safety and traffic related ones. Current systems rely on Global Positioning Systems (GPS) to obtain vehicle position. Accurate localization is imperative and GPS is known for its margin of error. In this paper, we investigate the use of Radio Frequency Identification (RFID) technology in our SmartDrive vehicular network testbed to complement GPS in order to obtain more accurate localization. We conduct both indoor and outdoor experiments to test both range and durability of RFID.