Mitigating External Threats in Wireless Local Area Networks

As computer networks become more critical to enterprises, it is inevitable that efficient security policies are designed, case in point: wireless networks, in order to effectively ensure the confidentiality, availability, and integrity of the data traversing these networks. The primary objective of this paper is to appropriately simulate an enterprise network, and evaluate the threats, and possible mitigation approaches applicable. An analysis of an enterprise WLAN (Wireless Local Area Network) was carried out, to identify relevant vulnerabilities, and possible countermeasures against these threats. The primary threats analysed were those possible by an external adversary. Upon identification of said threats, a security model was developed, so as to improve enterprise network security, and ensure the levels are optimum. In addition, a number of the principles involved are applicable to non-wireless networks.   Keywords: WLAN, Wireless, Security, WPA 2, IEEE 802.11. 

Multi-Channel Distributed Coordinated Function over Single Radio in Wireless Sensor Networks

Multi-channel assignments are becoming the solution of choice to improve performance in single radio for wireless networks. Multi-channel allows wireless networks to assign different channels to different nodes in real-time transmission. In this paper, we propose a new approach, Multi-channel Distributed Coordinated Function (MC-DCF) which takes advantage of multi-channel assignment. The backoff algorithm of the IEEE 802.11 distributed coordination function (DCF) was modified to invoke channel switching, based on threshold criteria in order to improve the overall throughput for wireless sensor networks (WSNs) over 802.11 networks. We presented simulation experiments in order to investigate the characteristics of multi-channel communication in wireless sensor networks using an NS2 platform. Nodes only use a single radio and perform channel switching only after specified threshold is reached. Single radio can only work on one channel at any given time. All nodes initiate constant bit rate streams towards the receiving nodes. In this work, we studied the impact of non-overlapping channels in the 2.4 frequency band on: constant bit rate (CBR) streams, node density, source nodes sending data directly to sink and signal strength by varying distances between the sensor nodes and operating frequencies of the radios with different data rates. We showed that multi-channel enhancement using our proposed algorithm provides significant improvement in terms of throughput, packet delivery ratio and delay. This technique can be considered for WSNs future use in 802.11 networks especially when the IEEE 802.11n becomes popular thereby may prevent the 802.15.4 network from operating effectively in the 2.4 GHz frequency band

Multi-Channel Multi-Radio Using 802.11 Based Media Access for Sink Nodes in Wireless Sensor Networks

The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and data over IP networks instead of standalone video circuits. These systems will increase their reliability in the future on wireless networks and on IEEE 802.11 networks. However, due to limited non-overlapping channels, delay, and congestion there will be problems at sink nodes. In this paper we provide necessary conditions to verify the feasibility of round robin technique in these networks at the sink nodes by using a technique to regulate multi-radio multichannel assignment. We demonstrate through simulations that dynamic channel assignment scheme using multi-radio, and multichannel configuration at a single sink node can perform close to optimal on the average while multiple sink node assignment also performs well. The methods proposed in this paper can be a valuable tool for network designers in planning network deployment and for optimizing different performance objectives

Aboriginal Children and Their Caregivers Living with Low Income: Outcomes from a Two-Generation Preschool Program

The development of preschool children of Aboriginal heritage is jeopardized by the inter-generational transmission of risk that has created, and continues to create, social disadvantage. Early intervention programs are intended to mitigate the impact of social disadvantage. Yet, evidence of the effectiveness of these programs for children of Aboriginal heritage is limited. The purpose of this study was to examine the effects of a two-generation, multi-cultural preschool program on 45 children of Aboriginal heritage and their caregivers. We used a single-group, pretest (program intake)/posttest (program exit) design with follow-up when the children were 7 years old. We used an observational measure of child receptive language (Peabody Picture Vocabulary Test–III) and caregiver-reported measures of child development (Nipissing District Developmental Screen), risk for child maltreatment (Adult-Adolescent Parenting Inventory; AAPI), parenting stress (Parenting Stress Index; PSI), self-esteem (Rosenberg Self-Esteem scale; RSE), and life skills (Community Life Skills scale; CLS). Using paired t-tests we found statistically significant increases in child receptive language scores between intake and exit, and repeated-measures ANOVA showed that these improvements were maintained up to age 7 years. For caregivers, Pearson’s correlations demonstrated that risk for child maltreatment, parenting stress, self-esteem, and life skills were stable over time. Results of this study suggest that children of Aboriginal heritage can benefit from participation in a two-generation, multi-cultural preschool program. Their caregivers may have received greater benefit if issues of intergenerational transmission of the negative influences of residential schools were addressed as part of programming

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Multi-Channel Framework for Body Area Network in Health Monitoring

Abstract: Increasing use of wireless networks has empowered the facility of ubiquitous health monitoring especially in advanced countries. Various small devices are attached to human body forming personalized wireless body area network (WBAN). These small devices interact with each other using different radios and antennas schemes proposed by many researchers around the globe. However, most of these schemes are facing problem of inefficiency due to fading and shadowing effects. We propose a novel multi-radio multichannel framework for efficient communication among devices in WBAN. The focus of this research is to ensure energy efficient and reliable communication in WBAN

Multi-Channel Framework for Body Area Network in Health Monitoring

Increasing use of wireless networks has empowered the facility of ubiquitous health monitoring especially in advanced countries. Various small devices are attached to human body forming personalized wireless body area network (WBAN). These small devices interact with each other using different radios and antennas schemes proposed by many researchers around the globe. However, most of these schemes are facing problem of inefficiency due to fading and shadowing effects. We propose a novel multi-radio multichannel framework for efficient communication among devices in WBAN. The focus of this research is to ensure energy efficient and reliable communication in WBAN

Walking the Talk: Moving Indigenous Studies from the Classroom to the Community

In this session students will showcase their final assignments from the course Anthropology 4050: Canadian Status/Treaty Indian Reserve Communities. Throughout the course we have discussed the complexities of the history of the reserve system in Canada, the nuances of the Treaty process, the rigidity of the Indian Act, the traumas of residential schools and lived implications of forced relocations on Indigenous communities. We have examined how colonial relations are spatialized and how this spacialization translates into lived social relations. This showcase represents our desire to share what we have learned and why it matters with our TRU community in the hopes of nurturing a space of understanding, compassion, and mutually respectful conversation