Search results for "Communications protocol"
showing 10 items of 76 documents
Clustering-Based Protocol Classification via Dimensionality Reduction
2015
We propose a unique framework that is based upon diffusion processes and other methodologies for finding meaningful geometric descriptions in high-dimensional datasets. We will show that the eigenfunctions of the generated underlying Markov matrices can be used to construct diffusion processes that generate efficient representations of complex geometric structures for high-dimensional data analysis. This is done by non-linear transformations that identify geometric patterns in these huge datasets that find the connections among them while projecting them onto low dimensional spaces. Our methods automatically classify and recognize network protocols. The main core of the proposed methodology…
Sensor-Oriented Passive RFID
2010
This chapter addresses the design of new UHF tag antennas for sensing applications able to host detectors and additional electronics but also to act as passive sensor itself for some modification of the target. Starting from the consideration that the tag is both a digital and an analog device, sensing data may be achieved without using microcontrollers by a simple signal processing of the tag response and of the turn-on power. The chapter is particularly focused on the monitoring of human body features even if the proposed ideas and devices, here demonstrated by simulations and experimentation, may also be applied in a variety of scenarios.
A MANET Autoconfiguration System based on Bluetooth Technology
2006
The availability of both Wi-Fi and Bluetooth technologies on currently available devices offers the possibility to combine both in order to make the most out of their capabilities. In this paper we propose using Bluetooth technology to solve the configuration problem of the terminals conforming an IEEE 802.11-based ad-hoc network. The main objective of mobile ad- hoc networks (MANETs) is to extend the connectivity range of nodes through packet forwarding, thereby avoiding the use of a fixed infrastructure. However, since configuration of nodes is a complex issue, we provide a fast and reliable solution to auto-configure MANET terminals. Our solution is adequate for the quick setup and deplo…
FUZZY TCP: A PRELIMINARY STUDY
2002
Implementing efficient TCP for the Internet necessarily has to cope with the problem that the source does not know in advance which window allocation policy should be the best to use for a given network condition. In this paper, an on-line adaptive fuzzy system is used at the source in an objective to find the best possible weighted combination among the available policies.
Transport Protocols for Remote Programming of Network Robots within the context of Telelaboratories for Education: A Comparative Analysis
2007
Within the context of tele-laboratories for education the use of the Internet as communication media permits any researcher/student to perform remote experiments in a simple and reliable manner. Moreover, this situation introduces many interesting issues like network protocols for Internet robots, the effects of variable bandwidth and time-delays on telerobotics, etc. In this paper we present a comparative analysis of using several Internet transport protocols when performing a remote experiment within the UJI Industrial Telelaboratory. TCP, UDP, Trinomial and TEAR protocols are analyzed using the NS2 simulator. Conclusions show a set of characteristics the authors of this paper consider ve…
VII: Diagnosestudien: Einfache Maße für Validität und Reliabilität
2003
The evaluation of a new diagnostic or imaging device has to focus both on its diagnostic validity and reliability. Cohen's kappa coefficient can be used to assess the agreement of the new device's findings with those of an established diagnostic reference, it therefore presents a surrogate measure of validity. Additional measures of validity are sensitivity and specificity, which assess the order of agreement with the reference for positive and negative reference findings, respectively. The latter, however, can only be applied for binary reference findings. If discordant findings are observed, the McNemar test can be used to detect a diagnostic shift between diagnostic novum and reference. …
Distributed construction of quantum fingerprints
2003
Quantum fingerprints are useful quantum encodings introduced by Buhrman, Cleve, Watrous, and de Wolf (Physical Review Letters, Volume 87, Number 16, Article 167902, 2001; quant-ph/0102001) in obtaining an efficient quantum communication protocol. We design a protocol for constructing the fingerprint in a distributed scenario. As an application, this protocol gives rise to a communication protocol more efficient than the best known classical protocol for a communication problem.
Passive UHF RFID antennas for sensing applications: Principles, methods, and classifcations
2013
UHF passive radio-frequency identification technology is rapidly evolving from simple labeling of things to wireless pervasive sensing. A remarkable number of scientific papers demonstrate that objects in principle can have their physical properties be remotely tracked and monitored all along their life cycle. The key background is a new paradigm of antenna design that merges together the conventional communication issues with more-specific requirements about sensitivity to time-varying boundary conditions. This paper presents a unified review of the state of the art of the tag-as-sensor problem. Particular care is taken to formalize the measurement indicators and the communication and sens…
Implementation of Universal Digital Architecture using 3D-NoC for Mobile Terminal
2014
International Conference on Control, Decision and Information Technologies (CoDIT), Ecole Natl Ingenieurs Metz, Metz, FRANCE, NOV 03-05, 2014; International audience; The need to integrate multiple wireless communication protocols into a single low-cost flexible hardware platform is prompted by the increasing number of emerging communication protocols and applications in modern embedded systems. So the current challenge is to design of new digital architectures, in addition to its ability to take over of many functions. In this paper we have identified similarities between the despreader units in Rake receiver and the processor element in FFT-SDF (Fast Fourier Transform-Single path Delay Fe…
Guaranteed access mode for downlink traffic over IEEE 802.11 WLANs
2011
IEEE 802.11 networks present an unfairness problem between the downlink and uplink traffic, using the default settings of the Enhanced Distributed Channel Access (EDCA). In order to reduce this unfairness, the Access Point (AP) can adapt the standard parameters, but this is not enough. In this paper, we propose simple and efficient solutions, which are implemented at the AP, thus they are standard compatible and no modifications to the current hardware and protocol stacks are needed. These solutions aim at providing guaranteed access to the downlink traffic when the AP perceives the unfairness problem. Our simulation results show a reduction in the unfairness and an enhancement in network p…