Predicting Performance of Channel Assignments in Wireless Mesh Networks through Statistical Interference Estimation

Wireless Mesh Network (WMN) deployments are poised to reduce the reliance on wired infrastructure especially with the advent of the multi-radio multi-channel (MRMC) WMN architecture. But the benefits that MRMC WMNs offer viz., augmented network capacity, uninterrupted connectivity and reduced latency, are depreciated by the detrimental effect of prevalent interference. Interference mitigation is thus a prime objective in WMN deployments. It is often accomplished through prudent channel allocation (CA) schemes which minimize the adverse impact of interference and enhance the network performance. However, a multitude of CA schemes have been proposed in research literature and absence of a CA performance prediction metric, which could aid in the selection of an efficient CA scheme for a given WMN, is often felt. In this work, we offer a fresh characterization of the interference endemic in wireless networks. We then propose a reliable CA performance prediction metric, which employs a statistical interference estimation approach. We carry out a rigorous quantitative assessment of the proposed metric by validating its CA performance predictions with experimental results, recorded from extensive simulations run on an ns-3 802.11g environment

Reliable Prediction of Channel Assignment Performance in Wireless Mesh Networks

The advancements in wireless mesh networks (WMN), and the surge in multi-radio multi-channel (MRMC) WMN deployments have spawned a multitude of network performance issues. These issues are intricately linked to the adverse impact of endemic interference. Thus, interference mitigation is a primary design objective in WMNs. Interference alleviation is often effected through efficient channel allocation (CA) schemes which fully utilize the potential of MRMC environment and also restrain the detrimental impact of interference. However, numerous CA schemes have been proposed in research literature and there is a lack of CA performance prediction techniques which could assist in choosing a suitable CA for a given WMN. In this work, we propose a reliable interference estimation and CA performance prediction approach. We demonstrate its efficacy by substantiating the CA performance predictions for a given WMN with experimental data obtained through rigorous simulations on an ns-3 802.11g environment.Comment: Accepted in ICACCI-201

Radio Co-location Aware Channel Assignments for Interference Mitigation in Wireless Mesh Networks

Designing high performance channel assignment schemes to harness the potential of multi-radio multi-channel deployments in wireless mesh networks (WMNs) is an active research domain. A pragmatic channel assignment approach strives to maximize network capacity by restraining the endemic interference and mitigating its adverse impact on network performance. Interference prevalent in WMNs is multi-faceted, radio co-location interference (RCI) being a crucial aspect that is seldom addressed in research endeavors. In this effort, we propose a set of intelligent channel assignment algorithms, which focus primarily on alleviating the RCI. These graph theoretic schemes are structurally inspired by the spatio-statistical characteristics of interference. We present the theoretical design foundations for each of the proposed algorithms, and demonstrate their potential to significantly enhance network capacity in comparison to some well-known existing schemes. We also demonstrate the adverse impact of radio co- location interference on the network, and the efficacy of the proposed schemes in successfully mitigating it. The experimental results to validate the proposed theoretical notions were obtained by running an exhaustive set of ns-3 simulations in IEEE 802.11g/n environments.Comment: Accepted @ ICACCI-201

Towards service-oriented ontology-based coordination

Coordination is a central problem in distributed computing. The aim is towards flexible coordination, managed at run-time, in open, dynamic environments. This approach would benefit from an explicit common vocabulary for coordination and hence, in a previous paper, we modelled coordination in an ontology, describing the activities carried out and the interdependencies among these activities. The purpose of this paper is to show how such an ontology can be used alongside a set of rules to perform coordination by managing the interdependencies among activities. The ontology and rules can then be used to provide a general purpose coordination tool in the form of a Web servic

Min-O-Mee: A Proximity Based Network Application Leveraging The AllJoyn Framework

Close proximity of mobile devices can be utilized to create ad hoc and dynamic networks. These mobile Proximity Based Networks (PBNs) are Opportunistic Networks that enable devices to identify and communicate with each other without relying on any communication infrastructure. In addition, these networks are self organizing, highly dynamic and facilitate effective real-time communication. These characteristics render them very useful in a wide variety of complex scenarios such as vehicular communication, e-health, disaster networks, mobile social networks etc. In this work we employ the AllJoyn framework from Qualcomm which facilitates smooth discovery, attachment and data sharing between devices in close proximity. We develop Min-O-Mee, a Minutes-of-Meeting app prototype in the Android platform, utilizing the AllJoyn framework. Min-O-Mee allows one of the participants to create a minutes-of-meeting document which can be shared with and edited by the other participants in the meeting. The app harnesses the spatial proximity of participants in a meeting and enables seamless data exchange between them. This characteristic allows Min-O-Mee to share not just minutes-of-meeting, but any data that needs to be exchanged among the participants, making it a versatile app. Further, we extend the basic AllJoyn framework to enable multi-hop communication among the devices in the PBN. We devise a novel routing mechanism that is suited to a proximity centric wireless network as it facilitates data routing and delivery over several hops to devices that are at the fringe of the PBN

Interference mitigation in wireless mesh networks through radio co-location aware conflict graphs

Wireless Mesh Networks (WMNs) have evolved into a wireless communication technology of immense interest. But technological advancements in WMNs have inadvertently spawned a plethora of network performance bottlenecks, caused primarily by the rise in prevalent interference. Conflict Graphs are indispensable tools used to theoretically represent and estimate the interference in wireless networks. We propose a generic algorithm to generate conflict graphs which is independent of the underlying interference model. Further, we propose the notion of radio co-location interference, which is caused and experienced by spatially co-located radios in multi-radio multi-channel WMNs. We experimentally validate the concept, and propose a new all-encompassing algorithm to create a radio co-location aware conflict graph. Our novel conflict graph generation algorithm is demonstrated to be significantly superior and more efficient than the conventional approach, through theoretical interference estimates and comprehensive experiments. The results of an extensive set of ns-3 simulations run on the IEEE 802.11g platform strongly indicate that the radio co-location aware conflict graphs are a marked improvement over their conventional counterparts. We also question the use of total interference degree as a reliable metric to predict the performance of a Channel Assignment scheme in a given WMN deployment

Optimal placement of Femto base stations in enterprise femtocell networks

Femto cells a.k.a. Low Power Nodes (LPNs) are deployed to improve indoor data rates as well as reduce traffic load on macro Base Stations (BSs) in 4G/LTE cellular networks. Indoor UEs getting high SNR (Signal-to-Noise Ratio) can experience good throughput, but SNR decreases at faster rate due to obstacles, present along the communication path. Hence, efficient placement of Femtos in enterprise buildings is crucial to attain desirable SNR for indoor users. We consider obstacles and shadowing effects by walls and include them in the system model. We develop a Linear Programming Problem (LPP) model by converting convex constraints into linear ones and solve it using GAMS tool, to place Femtos optimally inside the building. Our extensive experimentation proves the optimal placement of Femtos achieves 14.41% and 35.95% increase in SNR of indoor UEs over random and center placement strategies, respectively