Search results for "Computer network"
showing 10 items of 1634 documents
PRIVANET: An Efficient Pseudonym Changing and Management Framework for Vehicular Ad-Hoc Networks
2020
Protecting the location privacy is one of the main challenges in vehicular ad-hoc networks (VANETs). Although, standardization bodies, such as IEEE and ETSI, have adopted a pseudonym-based scheme as a solution for this problem, an efficient pseudonym changing and management is still an open issue. In this paper, we propose PRIVANET, a complete and efficient pseudonym changing and management framework. The PRIVANET has a hierarchical structure and considers the vehicular geographic area as a grid. Each cell of this grid contains one or many logical zones, called vehicular location privacy zones (VLPZs). These zones can easily be deployed over the widespread roadside infrastructures (RIs), su…
Recent advances in green industrial networking [Guest Editorial]
2016
The articles in this special section focus on green industrial networking. Due to the explosive increase in energy usage, it is essential that governmental and industrial institutions address this problem. Therefore, the development of green and low-carbon economy has recently become a hot issue in the industry. It is envisioned in such cases to meet the growing demands for industrial networking with limited resources. This is considered one of the challenges that needs to be addressed. Addressing such key problems will hopefully allow us to reach the realization of sustainable development. We believe that network technologies will be critical and will greatly contribute to achieving large-…
Memetic Engineering for Permanent Education in Line with Sustainable Growth
2012
Given the recent point of view of the European Commission regarding the implementation of a new strategy for sustainable growth and jobs, this paper emphasises the opportunity and urgency of supporting the EU 2020 strategy, providing an appropriate educational tool for the knowledge society. The main objectives are: a. adapting memetic engineering expressed in terms of General System Theory to the teaching component of permanent education based on bounded rationality and "Just in Time"as key tools for fighting cognitive chaoplexity in the post-industrial era; b. facilitating the use of memetic engineering based on its double-faceted nature: as both positive and negative feedback; c. extendi…
Learning failure in information systems development
1999
Information systems development is a high-risk undertaking, and fail- ures remain common despite advances in development tools and technologies. In this paper, we argue that one reason for this is the collapse of organizational intelligence required to deal with the complexities of systems development. Orga- nizations fail to learn from their experience in systems development because of limits of organizational intelligence, disincentives for learning, organizational designs and educational barriers. Not only have many organizations failed to learn, but they have also learned to fail. Over time they accept and expect poor perfor- mance while creating organizational myths that perpetuate sho…
An analytical model of a new packet marking algorithm for TCP flows
2005
In Differentiated Services networks, packets may receive a different treatment according to their Differentiateo Services Code Point (DSCP) label. As a consequence, packet marking schemes can also be devised to differentiate packets belonging to a same TCP flow, with the goal of improving the performance experienced. This paper presents an analytical model for an adaptive packet marking scheme proposed in our previous work. The model combines three specific sub-models aimed at describing (i) the TCP sources aggregate, (ii) the marker, and (iii) the network status. Preliminary simulation results show quite accurate predictions for throughput and average queue occupancy. Besides, the research…
Design & Optimization of Large Cylindrical Radomes with Subcell and Non-Orthogonal FDTD Meshes Combined with Genetic Algorithms
2021
The word radome is a contraction of radar and dome. The function of radomes is to protect antennas from atmospheric agents. Radomes are closed structures that protect the antennas from environmental factors such as wind, rain, ice, sand, and ultraviolet rays, among others. The radomes are passive structures that introduce return losses, and whose proper design would relax the requirement of complex front-end elements such as amplifiers. The radome consists mostly in a thin dielectric curved shape cover and sometimes needs to be tuned using metal inserts to cancel the capacitive performance of the dielectric. Radomes are in the near field region of the antennas and a full wave analysis of th…
A New Approach to the Modeling of Anisotropic Media with the Transmission Line Matrix Method
2021
A reformulation of the Transmission Line Matrix (TLM) method is presented to model non-dispersive anisotropic media. Two TLM-based solutions to solve this problem can already be found in the literature, each one with an interesting feature. One can be considered a more conceptual approach, close to the TLM fundamentals, which identifies each TLM in Maxwell’s equations with a specific line. But this simplicity is achieved at the expense of an increase in the memory storage requirements of a general situation. The second existing solution is a more powerful and general formulation that avoids this increase in memory storage. However, it is based on signal processing techniques and considerabl…
Is There a Predisposition towards the Use of New Technologies within the Traffic Field of Emerging Countries? The Case of the Dominican Republic
2021
Technological devices are becoming more and more integrated in the management and control of traffic in big cities. The population perceives the benefits provided by these systems, and, therefore, citizens usually have a favorable opinion of them. However, emerging countries, which have fewer available infrastructures, could present a certain lack of trust. The objective of this work is to detect the level of knowledge and predisposition towards the use of new technologies in the transportation field of the Dominican Republic. For this study, the National Survey on Mobility was administered to a sample of Dominican citizens, proportional to the ONE census and to sex, age and province. The k…
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.