Search results for "Wireless network"
showing 10 items of 163 documents
Towards a layer-less network architecture — A case from Wireless Sensor Networks
2011
Ad hoc and Wireless Sensor Networks (WSNs) form a challenging domain for existing network protocols and paradigms to fit into. The traditional models conceived for wired networking and adapted for wireless and mobile environments provide an inefficient and ungraceful outcome when exercised against highly dynamic and highly mobile nature of ad hoc wireless sensor networks. Efforts are being made to tweak existing (and sometimes create from scratch) principles and models that can provide a concrete framework for such newer paradigms. The momentum of the traditional layered architecture carried over from the wired networks to infrastructure based wireless networks pushes the same approaches as…
On Applications of Wireless Sensor Networks
2009
Wireless Sensor Networks (WSN) are ad-hoc networks in which small independent sensor nodes have limited energy, computational resources and wireless communication capabilities. Recently, both academia and industry have shown great interest in the area of Wireless Sensor Networks. This paper focuses on the practical applications in commerce and feasible future employment of WSNs. Continued advances of wireless communication technologies have led to the following fields of applications: habitat and environmental monitoring, security of buildings and property, oil and gas installations, mines and tunnels, emergency medical care, military applications. In the near future WSNs will certainly ent…
CiNetView - Graphic Interface for Wireless Sensor Network Deployment and Monitoring
2010
Reliable communication is crucial for successful deployment of a wireless sensor network. Many environmental factors can affect the performance of radio links, and the deployment of a network without real-time information about link qualities can be a demanding task. This paper describes the CiNetView application that is intended to support the deployment and monitoring of wireless sensor network. CiNetView is based on diagnostic information collected by sensor nodes, and it allows the user to see a graphical presentation of the network topology and to monitor the network diagnostic information in real time.
The Role of ICT Actors and Networks in Development: The Case Study of a Wireless Project in Nepal
2011
The role of ICT actors in the formation and extension of ICT4D projects is important. The actors through their extended network and aligned interest can enhance the effectiveness of the project which in turn enables socioeconomic development opportunities. However, few studies have been conducted to understand the role of these central players. The objective of this paper, therefore, is to address this knowledge gap by conducting a qualitative case study in the Myagdi district in the mountain region of Nepal. In this study we explored the Nepal Wireless Networking Project (NWNP) and examined how an activist started it from one mountain village and gradually extended across more than 150 vil…
Best compromise solution for a new multiobjective scheduling problem
2006
In future wireless networks, a mobile terminal will be able to communicate with a service provider using several network connections. These connections to networks will have different properties and they will be priced separately. In order to minimize the total communication time and the total transmission costs, an automatic method for selecting the network connections is needed. Here, we describe the network connection selection problem and formulate it mathematically. We discuss solving the problem and analyse different multiobjective optimization approaches for it.
On the approximability of the range assignment problem on radio networks in presence of selfish agents
2005
AbstractWe consider the range assignment problem in ad-hoc wireless networks in the context of selfish agents: A network manager aims to assigning transmission ranges to the stations in order to achieve strong connectivity of the network within a minimal overall power consumption. Station is not directly controlled by the manager and may refuse to transmit with a certain transmission range because it might be costly in terms of power consumption.We investigate the existence of payment schemes which induce the stations to follow the decisions of a network manager in computing a range assignment, that is, truthful mechanisms for the range assignment problem. We provide both positive and negat…
A heuristic for fast convergence in interference-free channel assignment using D1EC coloring
2010
This work proposes an efficient method for solving the Distance-1 Edge Coloring problem (D1EC) for the assignment of orthogonal channels in wireless networks with changing topology. The coloring algorithm is performed by means of the simulated annealing method, a generalization of Monte Carlo methods for solving combinatorial problems. We show that the simulated annealing-based coloring converges fast to a suboptimal coloring scheme. Furthermore, a stateful implementation of the D1EC scheme is proposed, in which network coloring is executed upon topology changes. The stateful D1EC is also based on simulated annealing and reduces the algorithm’s convergence time by one order of magnitude in …
A Delay-Centric Dynamic Resource Allocation Algorithm for Wireless Communication Systems Based on HNN
2008
This paper proposes a dynamic resource-allocation (DRA) algorithm for packet data services in wireless communication systems based on Hopfleld neural networks (HNNs). The resource-allocation algorithm assumes a delay-centric approach in that it maximizes resource utilization of the overall system while minimizing the packet delay. The real-time (RT) working capability of HNN hardware implementation means that a very powerful scheduling DRA algorithm can be obtained. A generic formulation of the algorithm is presented to establish the optimal bit rate allocation. In addition, some illustrative examples of this formulation are given, considering specific wireless communication systems, such a…
Level-Crossing Rate and Average Duration of Fades of the Envelope of Mobile-to-Mobile Fading Channels in Cooperative Networks Under Line-of-Sight Con…
2008
This paper studies the fading behavior of mobile- to-mobile (M2M) fading channels in relay-based cooperative networks under line-of-sight (LOS) conditions. Here, we assume that LOS components exist in both the direct link between the source mobile station (SMS) and the destination mobile station (DMS) as well as in the link via the mobile relay (MR). In such a propagation environment, the fading channel is referred to as the multiple-LOS second-order scattering (MLSS) channel. The fading behavior of MLSS channels is studied by analyzing the level-crossing rate (LCR) and the average duration of fades (ADF) of the received envelope. We have derived analytical expressions for the LCR, ADF, and…
What's New for QoS in IEEE 802.11?
2013
Two amendments to IEEE 802.11 have recently been published: 802.11aa and 802.11ae. Both enhance Quality of Service (QoS) provisioning in Wi-Fi networks by providing support for multicast transmission, enhanced audio video streaming, coping with inter-network interference, and improved prioritization of management frames. The proposed solutions either extend mechanisms already existing in the standard or introduce new ones. Therefore, it is important for researchers to understand the new functionalities. To this end we provide the first description of these latest mechanisms: we present the motivation behind them, explain their design principles, provide examples of usage, and comment on com…