• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 385
  • 123
  • 63
  • 54
  • 49
  • 24
  • 23
  • 18
  • 12
  • 10
  • 9
  • 8
  • 6
  • 5
  • 5
  • Tagged with
  • 905
  • 323
  • 299
  • 184
  • 155
  • 152
  • 145
  • 143
  • 127
  • 112
  • 90
  • 86
  • 82
  • 80
  • 74
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Network Admission Control (NAC)Securing end point devices

Yusuf, Adewale, Lartey, Jerry, Wareus, Vilhelm January 2010 (has links)
There have been remarkable growths in wireless communication networks in recent years; this is because of its merits over the wired networks such as Mobility and convenience. Wireless networks transmit the signal over the open air via radio waves of different frequencies, this makes it to be vulnerable to several attacks and anybody on the street can easily intercept the wireless data or inject new data into the entire network. There has been existence of wired equivalent privacy (WEP) protocol (IEEE 802.11i), which was designed for wireless network security. There were concerns of security vulnerabilities in WEP; this made it necessary for the implementation of another solution to overcome the weaknesses of the previous wireless network security. The IEEE 802.1X (port-based network admission control) which is defined on Extensible Authentication protocol (EAP) provides effective and efficient admission control to wireless and other networks devices [8]. Our thesis investigates the efficiency of NAC (IEEE 802.1X) as a security solution, access different vendor solutions, protocols supported and look into the inter-operability of these various vendors. In as much as we support the premise of NAC being an excellent solution, we will also make brilliant recommendations in this thesis to be considered for future refinements of this security solution as well as deployment scenarios for the university network.
32

Enhanced IEEE 802.11.p-Based MAC Protocols for Vehicular Ad hoc Networks

Nasrallah, Yamen January 2017 (has links)
The Intelligent Transportation System (ITS) is a cooperative system that relies on reliable and robust communication schemes among vehicles and between vehicles and their surroundings. The main objective of the ITS is to ensure the safety of vehicle drivers and pedestrians. It provides an efficient and reliable transportation system that enhances traffic management, reduces congestion time, enables smooth traffic re-routing, and avoids economic losses. An essential part of the ITS is the Vehicular Ad hoc Network (VANET). VANET enables the setup of Vehicle-to-Vehicle (V2V) as well as Vehicle-to-Infrastructure (V2I) communication platforms: the two key components in the ITS. The de-facto standard used in wireless V2V and V2I communication applications is the Dedicated Short Range Communication (DSRC). The protocol that defines the specifications for the Medium Access Control (MAC) layer and the physical layer in the DSRC is the IEEE 802.11p protocol. The IEEE 802.11p protocol and its Enhanced Distributed Channel Access (EDCA) mechanism are the main focus of this thesis. Our main objective is to develop new IEEE 802.11p-based protocol for V2V and V2I communication systems, to improve the performance of safety-related applications. These applications are of paramount importance in ITS, because their goal is to decrease the rate of vehicle collisions, and hence reduce the enormous costs associated with them. In fact, large percentage of vehicle collisions can be easily avoided with the exchange of relevant information between vehicles and the Road Side Units (RSUs) installed on the sides of the roads. In this thesis, we propose various enhancements to the IEEE 802.11p protocol to improve its performance by lowering the average end-to-end delay and increasing the average network throughput. We introduce multiple adaptive algorithms to promote the QoS support across all the Access Categories (AC) in IEEE 802.11p. We propose two adaptive backoff algorithms and two algorithms that adaptively change the values of the Arbitrary Inter-Frame Space (AIFS). Then we extend our model to be applied in a large-scale vehicular network. In this context, a multi-layer cluster-based architecture is adopted, and two new distributed time synchronization mechanisms are developed.
33

Design of a Fast Location-Based Handoff Scheme for Vehicular Networks

Wang, Yikun January 2013 (has links)
IEEE 802.11 is an economical and efficient standard that has been applied to vehicular networks. However, the long handoff latency of the standard handoff scheme for IEEE 802.11 has become an important issue for seamless roaming in vehicular environments, as more handoffs may be triggered due to the higher mobility of vehicles. This thesis presents a new and fast location-based handoff scheme particularly designed for vehicular environments. With the position and movement direction of a vehicle and the locations of the surrounding APs, our protocol is able to accurately predict several possible APs that the vehicle may visit in the future and to assign these APs different priority levels. APs on higher priority levels will be first scanned. Once a response to scanning from an AP is received, the scanning process ends immediately. A blacklist scheme is also used to exclude those APs that showed no response to the scanning during previous handoffs. Thus, time spent on scanning APs is supposed to be significantly reduced. The simulation results show that the proposed scheme attains not only a lower prediction error rate, but also a lower MAC layer handoff latency, and that it has a smaller influence on jitter and throughput; moreover, these results show that the proposed scheme has a smaller total number of handoffs than other handoff schemes.
34

Honeypot pro rodinu bezdrátových komunikačních protokolů IEEE 802.11 / Honeypot for wireless communication protocols of IEEE 802.11 family

Řezáč, Michal January 2020 (has links)
Objective of this master thesis solves possible way of WiFi Honeypot realisation, which is constructed to detecet malicious network activity and attacks in radio environment that uses a set of IEEE 802.11 protocols. A specific configuration was created on the mITX format motherboard and contains scripts and software for data collection, analysis and its evaluation. Based on information and knowledge about specific network attacks it is possible to identify data traffic leading to anomalies and detect possible network attack. The final device was tested in real use for long-term data collection and evaluation of network activity in the given location. This fulfills the main goal of this work, which is implementation of WiFi Honeypot with support for IEEE 802.11 protocols and with possible deployment for real use.
35

PERFORMANCE ANALYSIS OF PRIORITIZED TCP ACK SCHEMES IN THE IEEE 802.11e WLANs

THANGARAJ, ARUNA January 2007 (has links)
No description available.
36

Optimalizace bezdrátových WiFi distribuovaných sítí / Optimization of WiFi Distributed Nets

Žlůva, Ivan January 2009 (has links)
This thesis describes theoretic proposal and two practical realization of multi - point wireless network, first for communications between two endpoints and second for wireless signal coverage of a structured space. The wireless network is realized by the equipment working in unlicenced 2,4GHz and 5GHz ISM band. The wireless device are configured in three different wireless mods: WDS, WDS bridge and AP. This paper contains short information about IEEE 802.11a/b/g/n standard and associated proprietary wireless specifications. Practical workshop describes several variants connections and present the result of throughtput measurements, depending on wireless network topology.
37

Implementing & Evaluating A Standardised MapRepresentation

Persson, Fredrik January 2021 (has links)
Maps are essential in the robots of today, not only to navigate but also to perform actions.This project’s aim was to create a program able to take map files of older standards suchas ROS Gridmaps or the current IEEE 2D map standard 1873-2015[2] and convert themto the new IEEE P2751/D1[4] standard. The new IEEE P2751/D1 is based of IEEE1873-2015 but improves by allowing 3D map formats such as Pointclouds or Voxel-gridsto be incorporated. This projects main goal was to have a program that is able to convertfrom some of these different map types into the new standard. The existence of sucha program eases any future adaptation. This report also includes a detailed evaluationof the efficiency of the IEEE P2751/D1 standard format in comparison to other mapformats.
38

Optimalizace bezdrátových WiFi distribuovaných sítí / Optimization of WiFi Distributed Nets

Žlůva, Ivan January 2010 (has links)
This thesis describes theoretic proposal and two practical realization of multi - point wireless network, first for communications between two endpoints and second for wireless signal coverage of a structured space. The wireless network is realized by the equipment working in unlicenced 2,4GHz and 5GHz ISM band. The wireless device are configured in three different wireless mods: WDS, WDS bridge and AP. This paper contains short information about IEEE 802.11a/b/g/n standard and associated proprietary wireless specifications. Practical workshop describes several variants connections and present the result of throughtput measurements, depending on wireless network topology.
39

1588-ENHANCED VEHICLE NETWORK CONCEPT DEMONSTRATION

Grace, Thomas, Roach, John 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / CTEIP has launched the integrated Network Enhanced Telemetry (iNET) project to foster advances in networking and telemetry technology to meet emerging needs of major test programs as well as within the Major Range and Test Facility Base’s. This paper describes one objective of the vNET concept demonstration to provide a test vehicle instrumentation network architecture that can support additional capabilities for data access to the test vehicle. Specifically, this paper addresses the expansion of the current concept demonstration with the incorporation of the IEEE- 1588 standard as the basis for a network time distribution mechanism. Near-term network-based data acquisition systems will likely consist of a mix of standard IRIG 106 timekeeping and IEEE- 1588 timekeeping; in this paper we will examine the ramifications of using the two approaches with the same test vehicle instrumentation system.
40

IEEE 1451 SMART TRANSDUCER STANDARDS: STATUS, GOING WIRELESS, AND PULLING IT ALL TOGETHER

Jones, Charles H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / There are seven parts of the Institute of Electrical and Electronics Engineers (IEEE) 1451 Smart Transducer family of standards either approved, in work, or in review. These documents are providing a nonproprietary set of standards for the implementation of smart transducers (i.e., sensors and actuators). This paper overviews these standards and their status. In particular, the IEEE P1451.5, which addresses wireless transducers, and the IEEE P1451.0, which will provide a common high level architecture for the entire family, will be discussed. A reference model, which is being used as a focus for the IEEE P1451.0, will be introduced to help show the relation between all the members of the family.

Page generated in 0.0451 seconds