Search results for "Wireless network"

Coloring-based resource allocations in ad-hoc wireless networks

2011

It is well known that CSMA/CA protocols exhibit very poor performance in case of multi-hop transmissions, because of inter-link interference due to imperfect carrier sensing. We propose to control such an interference by preallocating temporal slots in which different sets of network nodes are allowed to contend for the channel access. The approach is based on distributed coloring algorithms with limited signaling overhead that can be customized as a function of the network topology and traffic load.

Method of changing the operation of wireless network nodes

2013

Robust Data Gathering for Wireless Sensor Networks

2006

2005 13th IEEE International Conference on Networks jointly held with the 2005 7th IEEE Malaysia International Conference on Communications, Proceedings Volume 1, 2005, Article number 1635527, Pages 469-474 2005 13th IEEE International Conference on Networks jointly held with the 2005 7th IEEE Malaysia International Conference on Communications; Kuala Lumpur; Malaysia; 16 November 2005 through 18 November 2005; Category number05EX1235; Code 69262 Robust data gathering for wireless sensor networks (Conference Paper) Ortolani, M. , Gatani, L. , Lo Re, G. Dipartimento di Ingegneria Informatica, Università degli Studi di Palermo, Viale delle Scienze Parco d'Orleans, 90128 Palermo, Italy View re…

A scalable platform for safe and secure decentralized traffic management of multiagent mobile systems

2006

In this paper we describe the application of wireless sensor networking techniques to address the realization of a safe and secure decentralized traffic management system. We consider systems of many heterogeneous autonomous vehicles moving in a shared environment. Each vehicle is assumed to have different and possibly unspecified tasks, but they cooperate to avoid collisions. We are interested in designing a scalable architecture capable of accommodating a very large and dynamically changing number of vehicles, guaranteeing their safety, the achievement of their goals, and security against potential adversaries. By properly distributing and revoking cryptographic keys we are able to protec…

Design of SCMA Codebooks using Differential Evolution

2020

Non-orthogonal multiple access (NOMA) is a promising technology which meets the demands of massive connectivity in future wireless networks. Sparse code multiple access (SCMA) is a popular code-domain NOMA technique. The effectiveness of SCMA comes from: (1) the multi-dimensional sparse codebooks offering high shaping gain and (2) sophisticated multi-user detection based on message passing algorithm (MPA). The codebooks of the users play the main role in determining the performance of SCMA system. This paper presents a framework to design the codebooks by taking into account the entire system including the SCMA encoder and the MPA-based detector. The symbol-error rate (SER) is considered as…

Data Communication Security of Advanced Metering Infrastructure in Smart Grid

2013

Advanced Metering Infrastructure (AMI) is very critical part for wired/wireless communication in Smart Grid. It involves communication of vital smart metering data to central control center for smooth functioning of smart grid. Security and reliability of data is of paramount importance for operational reliability of smart grid. AMI network is susceptible to many cyber security threats and attacks. Therefore it is desirable to prevent the data from such vulnerabilities. The paper proposes two-phase method to provide security of data using dedicated authentication server which inhibits malicious and unauthorized nodes to gain access to AMI communication network. Secure environment is created…

Invariant aspects in M-commerce environments

2005

Mobile phones and other small and powerful portable devices have revolutionized personal communication and affected the lifestyles of the people in the industrialized world. Following credible estimates, in a few years there will over two - billions of such portable devices in use. An emerging trend is the electronic commerce performed using mobile terminals over wireless networks, often called mobile commerce or M-commerce. Mobile commerce environments are characterized by high complexity, including myriads of technical and organizational aspects. This property makes it difficult to distinguish the more fundamental issues, structures, and concepts in mobile commerce from the hype. To captu…

Exploiting programmable architectures for WiFi/ZigBee inter-technology cooperation

2014

The increasing complexity of wireless standards has shown that protocols cannot be designed once for all possible deployments, especially when unpredictable and mutating interference situations are present due to the coexistence of heterogeneous technologies. As such, flexibility and (re)programmability of wireless devices is crucial in the emerging scenarios of technology proliferation and unpredictable interference conditions. In this paper, we focus on the possibility to improve coexistence performance of WiFi and ZigBee networks by exploiting novel programmable architectures of wireless devices able to support run-time modifications of medium access operations. Differently from software…

Cross-technology wireless experimentation: Improving 802.11 and 802.15.4e coexistence

2016

In this demo we demonstrate the functionalities of a novel experimentation framework, called WiSHFUL, that facilitates the prototyping and experimental validation of innovative solutions for heterogeneous wireless networks, including cross-technology coordination mechanisms. The framework supports a clean separation between the definition of the logic for optimizing the behaviors of wireless devices and the underlying device capabilities, by means of a unifying platform-independent control interface and programming model. The use of the framework is demonstrated through two representative use cases, where medium access is coordinated between IEEE-802.11 and IEEE-802.15.4 networks.

Analysis of mobile-oriented energy consumption for heterogeneous connections in hybrid wireless networks

2012

While more and more mobile devices are equipped with both cellular and WLAN interfaces for internet access, the energy consumption aspect of these connections has not been studied in depth in the literature. In this paper, a hybrid network with three alternative wireless connections, namely, a cellular component, a combined component with a mixed ad hoc and cellular link, or an infrastructure-based WLAN component, is investigated. A distance-based analysis on the energy consumption of a mobile station has been performed for each alternative wireless connection, and corresponding numerical results have been obtained. The results suggest that, to increase link throughput while maintaining min…