Spelling suggestions: "subject:"link layer"" "subject:"link mayer""
21 |
Using Link Layer Information to Enhance Mobile IP Handover Mechanism. An investigation in to the design, analysis and performance evaluation of the enhanced Mobile IP handover mechanism using link layer information schemes in the IP environment.Alnas, Mohamed J.R. January 2010 (has links)
Mobile computing is becoming increasingly important, due to the rise in the number of
portable computers and the desire to have continuous network connectivity to the
Internet, irrespective of the physical location of the node. We have also seen a steady
growth of the market for wireless communication devices. Such devices can only have
the effect of increasing the options for making connections to the global Internet. The
Internet infrastructure is built on top of a collection of protocols called the TCP/IP
protocol suite. Transmission Control Protocol (TCP) and Internet Protocol (IP) are the
core protocols in this suite. There are currently two standards: one to support the current
IPv4 and one for the upcoming IPv6 [1]. IP requires the location of any node connected
to the Internet to be uniquely identified by an assigned IP address. This raises one of the
most important issues in mobility because, when a node moves to another physical
location, it has to change its IP address. However, the higher-level protocols require the
IP address of a node to be fixed for identifying connections.
The Mobile Internet Protocol (Mobile IP) is an extension to the Internet Protocol
proposed by the Internet Engineering Task Force (IETF) that addresses this issue. It
enables mobile devices to stay connected to the Internet regardless of their locations,
without changing their IP addresses and, therefore, an ongoing IP session will not be
interrupted [2, 3, 4]. More precisely, Mobile IP is a standard protocol that builds on the Internet Protocol by making mobility transparent to applications and higher-level
protocols like TCP. However, before Mobile IP can be broadly deployed, there are still
several technical barriers, such as long handover periods and packet loss that have to be
overcome, in addition to other technical obstacles, including handover performance,
security issues and routing efficiency [7].
This study presents an investigation into developing new handover mechanisms based on
link layer information in Mobile IP and fast handover in Mobile IPv6 environments. The
main goal of the developed mechanisms is to improve the overall IP mobility
performance by reducing packet loss, minimizing signalling overheads and reducing the
handover processing time. These models include the development of a cross-layer
handover scheme using link layer information and Mobile Node (MN) location
information to improve the performance of the communication system by reducing
transmission delay, packet loss and registration signalling overheads.
Finally, the new schemes are developed, tested and validated through a set of
experiments to demonstrate the relative merits and capabilities of these schemes.
|
22 |
To Determine Networked Telemetry Resynchronization TimeLaird, Daniel T. 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / The Central Test and Evaluation Investment Program (CTEIP) Integrated Network Enhanced Telemetry (iNET) program is currently testing networked telemetry transceivers (IP.TM-Tx/Rx) using the Internet Protocol (IP), for use in telemetry (TM) channels. A unique characteristic of networked telemetry channel is packet drops due to radio frequency (RF) signal dynamics, i.e., terrain, weather, aircraft attitude, manmade objects, etc.. One of the key measures of the IP.TMTx/ Rx is reliability is link availability (LA), and a key element of LA is time to resynchronize after RF link loss.
|
23 |
Implementace ethernetového komunikačního rozhraní do obvodu FPGA / Implementation of ethernet communication inteface into FPGA chipSkibik, Petr January 2011 (has links)
The thesis deals with the implementation of Ethernet-based network communication interface into FPGA chip. VHDL programming language is used for description of the hardware. The interface includes the implementation of link-layer Ethernet protocol and network protocols such as IPv4, ARP, ICMP and UDP. The final design allows bi-directional communication on the transport-layer level of TCP/IP model. The designed interface was implemented into Virtex5 FPGA chip on development board ML506 by Xilinx.
|
24 |
A Comprehensive Taxonomy of Attacks and Mitigations in IoT Wi-Fi Networks : physical and data-link layerAlmjamai, Sarmed January 2022 (has links)
The number of Internet of Things (IoT) devices is rising and Wireless Fidelity (Wi-Fi) networks are still widely used in IoT networks. Security protocols such as Wi-Fi Protected Access 2 (WPA2) are still in use in most Wi-Fi networks, but Wi-Fi Protected Access 3 (WPA3) is making its way as the new security standard. These security protocols are crucial in Wi-Fi networks with energy and memory-constrained devices because of adversaries that could breach confidentiality, integrity, and availability of networks through various attacks. Many research papers exist on single Wi-Fi attacks, and the strengths and weaknesses of security protocols and Wi-Fi standards. This thesis aims to provide a detailed overview of Wi-Fi attacks and corresponding mitigation techniques against IoT Wi-Fi networks in a comprehensive taxonomy. In addition tools are mentioned for each Wi-Fi attack that allows, e.g., professionals or network administrators to test the chosen Wi-Fi attacks against their IoT networks. Four types of attack (categories) were defined, Man-in-the-Middle (MitM), Key-recovery, Traffic Decryption, and Denial of Service (DoS) attacks. A set of Wi-Fi attack features were defined and decribed. The features included the security protocol and security mode, the layer (physical or data-link) that an attack targets, and the network component interaction required to allow a Wi-Fi attack to execute successfully. In total, 20 Wi-Fi attacks were selected with relevance to IoT in Wi-Fi networks based on some criteria. Additonally, each Wi-Fi attack consist of a description of possible consequences/results an adversary can achieve, such as eavesdropping, data theft, key recovery, and many more. Flow charts were also added to give the reader a visual perspective on how an attack works. As a result, tables were created for each relevant security protocol and the Open Systems Interconnection (OSI) layers to create a overview of mitigations and available tools for each attack. Furthermore, WPA3 was discussed on how it solves some shortcomings of WPA2 but has vulnerabilities of it own that lie in the design of the 4-way and dragonfly handshake itself. In conclusion, development and proper vulnerability tests on the Wi-Fi standards and security protocols have to be conducted to improve and reduce the possibility of current and upcoming vulnerabilities.
|
25 |
Vliv přenosových parametrů na spotřebu elektrické energie Zigbee zařízení / Impact of Communication Parameters on Energy Consumption of Zigbee DevicesPopelka, Jan January 2013 (has links)
This thesis deals with the energy research and design a simple wireless sensor networks. The data modules with ZigBee wireless communication technology. The main feature of wireless sensor networks is the minimal energy devices at low cost and maximum data reliability. Furthermore, the work describes firmware for communicating nodes with the ability to change parameters of data transmission and thus affect the energy consumption node. Calculations of energy consumption, compared with measured results and discharge characteristics of the battery packs are included in the final chapters of this work.
|
26 |
Vliv přenosových parametrů na spotřebu elektrické energie Zigbee zařízení / Impact of Communication Parameters on Energy Consumption of Zigbee DevicesPopelka, Jan January 2013 (has links)
This thesis deals with the energy research and design a simple wireless sensor networks. The data modules with ZigBee wireless communication technology. The main feature of wireless sensor networks is the minimal energy devices at low cost and maximum data reliability. Furthermore, the work describes firmware for communicating nodes with the ability to change parameters of data transmission and thus affect the energy consumption node. Calculations of energy consumption, compared with the measured results, the discharge characteristics of the battery packs and lifetime broadcasting node is contained in the final chapters of this work.
|
Page generated in 0.0404 seconds