The document discusses wireless local area networks (WLANs) and wireless networking concepts. It covers wireless standards such as 802.11a, 802.11b, 802.11g and 802.11n. It describes wireless network components like access points, discusses wireless security issues and configurations, and provides guidance on troubleshooting common wireless network problems.
This document describes the design and implementation of a wireless digital notice board system using Wi-Fi technology. The system allows users to wirelessly transmit notice texts to an Arduino board connected to an LED display matrix from a web interface over Wi-Fi. The Arduino receives messages serially from the Wi-Fi module and controls the LED display matrix to show the notices. The system provides wireless updating of notices in places like schools and offices, eliminating the need for manual updating of traditional paper notice boards.
Visible Light Communication for Visually Impaired People using Sustainable LEDsijtsrd
We developed navigation system prototype for the visually impaired using LED lights. Where LED lights emit visible light with location data and a smartphone or blind persons stick with a visible light receiver receives the data. The controller with receiver calculates the optimal path to a designation and speaks to the visually impaired through a headphone or turns stick left or right with the help of motor. The prototype is able to navigate the visually impaired users fairly well with speech guidance. We believe that the application of visible light communication belongs to location-based services and new graphical user interfaces that combine visual imagery with visible light communication. For this application, users are able to know the information associated with a transmitter. If a transmitter is attached to a building or a fixed place, location information will be obtained. Indoor navigation is convenient for everyone, and it is especially useful for visually impaired. If a transmitter is attached to a building or a fixed place, location information will be obtained and conveyed to receiver using LED light. Indoor navigation is convenient for everyone, and it is especially useful for visually impaired. Pradnya Kulkarni | Prof. M. B. Tadwalkar"Visible Light Communication for Visually Impaired People using Sustainable LEDs" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-5 , August 2017, URL: http://www.ijtsrd.com/papers/ijtsrd2236.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/2236/visible-light-communication-for-visually-impaired-people-using-sustainable-leds/pradnya-kulkarni
Visible Light Communication in Defence and SecurityIRJET Journal
The document discusses using visible light communication (VLC) technology in defense and security applications. VLC uses LED lights to transmit data, providing a secure alternative to wireless communication that does not penetrate walls. It could replace optical fibers currently used for wiring in planes and vehicles. VLC offers high-speed communication confined to a small area, without interference from other signals. The document proposes using VLC for secure data transfer in defense conference halls and other indoor spaces. Challenges include shadowing and ensuring data can be modulated without causing flickering perceptible to humans.
This document is a laboratory manual for a Computer Networking lab course. It outlines 12 experiments for students to complete over the course of the semester related to networking concepts. The first experiment involves setting up a wired local area network (LAN) using a layer 2 switch and then an IP switch to connect a minimum of four computers. It includes preparing and testing cables, configuring machines with IP addresses, and using ping and Wireshark to test connectivity. The second experiment extends the first to implement the LAN wirelessly using an access point.
The document discusses different types of cables including their components, uses, and advantages/disadvantages. It describes coaxial cables which are used for audio/video transmission and have a center conductor, outer shield, insulation layer, and plastic jacket. Optical fiber cables transmit data using glass or plastic fibers and are used for long-distance telephone lines. Twisted pair cables have two independently insulated wires twisted together to reduce interference and are used widely in Ethernet networks. USB cables connect devices to computers to transfer data and power. Power cables transmit electrical power for various building and industrial applications.
Our major goal is to help you achieve your academic goals. We are commited to helping you get top grades in your academic papers.We desire to help you come up with great essays that meet your lecturer's expectations.Contact us now at http://www.premiumessays.net/
IRJET - Web-based Chatbot for Continuous Conversation using Artificial Intell...IRJET Journal
This document describes a web-based chatbot for continuous conversation using artificial intelligence. The proposed system uses a chatbot connected to an Arduino microcontroller and servo motor to provide dynamic answers through an MP3 module and mouth movements. The chatbot is designed to identify queries, respond verbally through the speaker, and move the servo motor to simulate mouth movements. It aims to provide an effective solution for conversational agents using technologies like fuzzy logic and natural language processing.
Li-Fi audio transmission is the transmission of wireless data by using visible light as a medium of communication in which the receiver section interprets the incoming light which is detected using a solar panel and converts to the audible sound signal with the help of a speaker.
This document describes the design and implementation of a wireless digital notice board system using Wi-Fi technology. The system allows users to wirelessly transmit notice texts to an Arduino board connected to an LED display matrix from a web interface over Wi-Fi. The Arduino receives messages serially from the Wi-Fi module and controls the LED display matrix to show the notices. The system provides wireless updating of notices in places like schools and offices, eliminating the need for manual updating of traditional paper notice boards.
Visible Light Communication for Visually Impaired People using Sustainable LEDsijtsrd
We developed navigation system prototype for the visually impaired using LED lights. Where LED lights emit visible light with location data and a smartphone or blind persons stick with a visible light receiver receives the data. The controller with receiver calculates the optimal path to a designation and speaks to the visually impaired through a headphone or turns stick left or right with the help of motor. The prototype is able to navigate the visually impaired users fairly well with speech guidance. We believe that the application of visible light communication belongs to location-based services and new graphical user interfaces that combine visual imagery with visible light communication. For this application, users are able to know the information associated with a transmitter. If a transmitter is attached to a building or a fixed place, location information will be obtained. Indoor navigation is convenient for everyone, and it is especially useful for visually impaired. If a transmitter is attached to a building or a fixed place, location information will be obtained and conveyed to receiver using LED light. Indoor navigation is convenient for everyone, and it is especially useful for visually impaired. Pradnya Kulkarni | Prof. M. B. Tadwalkar"Visible Light Communication for Visually Impaired People using Sustainable LEDs" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-5 , August 2017, URL: http://www.ijtsrd.com/papers/ijtsrd2236.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/2236/visible-light-communication-for-visually-impaired-people-using-sustainable-leds/pradnya-kulkarni
Visible Light Communication in Defence and SecurityIRJET Journal
The document discusses using visible light communication (VLC) technology in defense and security applications. VLC uses LED lights to transmit data, providing a secure alternative to wireless communication that does not penetrate walls. It could replace optical fibers currently used for wiring in planes and vehicles. VLC offers high-speed communication confined to a small area, without interference from other signals. The document proposes using VLC for secure data transfer in defense conference halls and other indoor spaces. Challenges include shadowing and ensuring data can be modulated without causing flickering perceptible to humans.
This document is a laboratory manual for a Computer Networking lab course. It outlines 12 experiments for students to complete over the course of the semester related to networking concepts. The first experiment involves setting up a wired local area network (LAN) using a layer 2 switch and then an IP switch to connect a minimum of four computers. It includes preparing and testing cables, configuring machines with IP addresses, and using ping and Wireshark to test connectivity. The second experiment extends the first to implement the LAN wirelessly using an access point.
The document discusses different types of cables including their components, uses, and advantages/disadvantages. It describes coaxial cables which are used for audio/video transmission and have a center conductor, outer shield, insulation layer, and plastic jacket. Optical fiber cables transmit data using glass or plastic fibers and are used for long-distance telephone lines. Twisted pair cables have two independently insulated wires twisted together to reduce interference and are used widely in Ethernet networks. USB cables connect devices to computers to transfer data and power. Power cables transmit electrical power for various building and industrial applications.
Our major goal is to help you achieve your academic goals. We are commited to helping you get top grades in your academic papers.We desire to help you come up with great essays that meet your lecturer's expectations.Contact us now at http://www.premiumessays.net/
IRJET - Web-based Chatbot for Continuous Conversation using Artificial Intell...IRJET Journal
This document describes a web-based chatbot for continuous conversation using artificial intelligence. The proposed system uses a chatbot connected to an Arduino microcontroller and servo motor to provide dynamic answers through an MP3 module and mouth movements. The chatbot is designed to identify queries, respond verbally through the speaker, and move the servo motor to simulate mouth movements. It aims to provide an effective solution for conversational agents using technologies like fuzzy logic and natural language processing.
Li-Fi audio transmission is the transmission of wireless data by using visible light as a medium of communication in which the receiver section interprets the incoming light which is detected using a solar panel and converts to the audible sound signal with the help of a speaker.
Whitepaper Advancements And Economics Make Vdsl Ideal Finaldandreladson
Video demand is driving the need for broadband networks capable of 100Mbps or more. Most providers are building hybrid networks using fiber for backbones and existing copper for last-mile connections due to much lower costs compared to full fiber networks. New VDSL technologies can deliver high speeds over copper at a fraction of the cost of fiber while meeting demand. VDSL uses techniques like bonding and vectoring to support high performance over copper for the foreseeable future.
Track e the road from 2 d to 3d integration -synopsyschiportal
This document discusses the transition from 2D to 3D integrated circuit design. It provides a brief history of stacking and through-silicon vias. While 3D integration provides benefits like higher bandwidth and smaller footprint, there are also challenges to address like cost overhead, yield loss, and complex design tools/flows. Key issues discussed are the large number and placement of through-silicon vias, and their impact on performance, power, and yield through stress proximity effects. Overall the document outlines both the promise and challenges of 3D design.
The document discusses computer networks and communication. It defines key network concepts like transmission methods, network categories, protocols, and internet terms. It explains the basic elements of communication including senders, mediums, receivers, and messages. It also summarizes different network types like LANs, WANs, intranets, and the internet. Finally, it outlines the OSI model layers and their functions in network communication.
This document discusses different types of guided media, including twisted pair cable, coaxial cable, and fiber optic cable. It provides details on the characteristics of each type of cable, such as their uses, advantages, and disadvantages. Twisted pair cable is commonly used for short distance digital data transmission at speeds up to 9600 bits per second. Coaxial cable has higher bandwidth and can transmit signals over longer distances compared to twisted pair. Fiber optic cable has the highest bandwidth capability and is less susceptible to interference, but is the most expensive option.
Nowadays, mobile consumer electronics devices integrate various wireless interfaces like WIFI, Bluetooth, GPRS and GPS. Various approaches exist to protect the wireless interfaces against ESD stress. In recent years, researchers have focused on so‐called 'co‐design' techniques to solve both functional and protection constraints together which requires both RF and ESD design skills. However many IC designers still prefer to work with 'plug‐n‐play' protection concepts where the ESD clamps exhibit low parasitic capacitance, low series resistance and low leakage. This paper presents measurement results of 3 different SCR based protection approaches that exhibit high Q‐factor and low and stable parasitic capacitance over a broad voltage and frequency range. The clamps are used for protection of LNA circuits in 90nm and 40nm Low Power (LP) CMOS technologies.
Li-Fi or optical Wi-Fi is a new technology that uses visible light communication (VLC) to transmit data wirelessly using LED lights. It provides higher speeds than Wi-Fi and is more secure as light cannot pass through walls. Li-Fi was first demonstrated by German physicist Harald Hass and uses pulsing LED lights to transmit binary code for wireless internet access. It has advantages over Wi-Fi such as no interference from radio frequencies, higher speeds up to 10 Gbps, and lower power consumption. Li-Fi is being commercialized by companies and can be used in applications like wireless networks at home or in hospitals where RF signals are restricted.
The document provides a proposal for implementing a VSAT connectivity solution for internet access. It describes what VSAT is, its applications, advantages over terrestrial networks, and then provides two pricing options - one with shared bandwidth and one with dedicated bandwidth. Key details include installation and setup within 7 days, 6 months warranty, and payment terms of 80% on order and 20% on activation. Overall the proposal outlines a turnkey satellite-based internet solution using VSAT technology.
IRJET- Highway Navigation System using Light Fidelity TechnologyIRJET Journal
This paper proposes a smart highway navigation system using Li-Fi (Light Fidelity) technology. Li-Fi uses visible light communication to transmit data using LED lights at speeds greater than Wi-Fi. The system would install Li-Fi transmitters in streetlights that would send location and direction data to vehicles equipped with Li-Fi receivers. The receivers would display the navigation information on an LCD screen. This system could provide automatic navigation for travelers on highways without needing mobile networks or GPS. It was simulated using Proteus software and the prototype had transmitters with microcontrollers and high-intensity LEDs and receivers with LDR photo detectors connected to another microcontroller and LCD display.
Manufacturer and Supplier of ST/PC Fiber Optical Patch Cord, Distribution Patch Cord, ST/PC MM.SM Adapter, ST/PC SM Attenuator(Adapter Type And Connector Type), SC/PC/APC Fiber Optical Patch Cord and SC/PC/APC Loopback Patch Cord.
This document is a catalogue for Havells India Ltd's wire and cable products. It provides an overview of the company, which manufactures electrical power distribution and transmission equipment across India and other countries. The catalogue then describes Havells' manufacturing process for cables, including details on the conductor, insulation, screening, armouring, and testing. It also lists the advantages of PVC and XLPE insulated cables. Finally, it notes that Havells has received NABL accreditation for its testing laboratory to ensure quality evaluation of its wire and cable products.
Gleam Electric and Power Company was incepted in 2013 and is supplying, trading, distributing and wholesaling a diverse range of Electrical Power Cables & Wires. Our product range is regarded by our clients for being interesting and includes Power Cables, Electrical Cables and Copper Flexible Wires. These cables are known for being long lasting, perfect in terms of finish, resistant to wear & tear and non corrosive.
Specialization in offering the world class range of Communication Devices that are sourced from the most reliable vendors in the market. The diversified range includes Multimeter, Optical Test Equipment, Under Ground Utility Locator, Fiber Optic Passive Components, LCD Display, RF Test Equipment, Fusion Splicing Machine and Accessories and various others.
This document discusses inter-VLAN routing and configuring a router to route between VLANs. It describes using router subinterfaces to allow a single physical router interface to route traffic for multiple VLANs by assigning each subinterface its own IP address and VLAN encapsulation. The document also briefly mentions using a multilayer switch for inter-VLAN routing and revising VLAN and trunk configuration as prerequisites.
The document discusses the key topics and concepts for designing a hierarchical LAN network, including the 3-level model consisting of core, distribution, and access layers. It covers choosing switches for each layer based on required features like port density, speed, redundancy, and layer 3 routing capability. The document also mentions incorporating voice and video traffic using quality of service and the advantages of a converged network supporting multiple traffic types over a single infrastructure.
The document discusses VLAN Trunking Protocol (VTP), which allows VLAN configurations to be automatically propagated across multiple switches to reduce configuration errors and maintenance. VTP operates by defining a VTP domain where one switch acts as a server to send VLAN information to other client switches. It describes how VTP advertisements are sent and processed to update switches when VLANs are added or modified on the server. The roles of server, client, and transparent modes are also outlined.
The document discusses switches and Ethernet networking concepts. It covers how switches work by building a MAC address table to forward frames, the operation of 100/1000 Mbps Ethernet, and configuring basic switch security. It also reviews related topics like collision domains, broadcast domains, latency, congestion, and switch forwarding methods.
The document discusses the Spanning Tree Protocol (STP) which eliminates switching loops in a converged network. STP runs on switches by default and works by disabling redundant links to form a spanning tree topology with no loops. It uses a three step algorithm to choose a root bridge, select root and designated ports, and block redundant ports. Rapid STP and per-VLAN STP were developed to improve convergence times.
The document discusses VLANs (virtual local area networks) and their role in dividing a network into logical segments. VLANs allow users to be grouped by function rather than physical location, improving flexibility. VLANs are configured on switches using port-based assignments and trunk links allow traffic from multiple VLANs to travel between switches using tagging. The document provides examples of configuring, monitoring and troubleshooting VLANs on Cisco switches.
This document discusses inter-VLAN routing, including using a router to enable communication between devices on different VLANs, configuring inter-VLAN routing on a router, and troubleshooting common inter-VLAN connectivity issues. It explains that inter-VLAN routing requires a router or layer 3 switch to route traffic between VLANs and that a traditional method uses multiple router interfaces connected to separate VLANs, while router-on-a-stick uses router subinterfaces connected to a layer 2 switch, with each subinterface needing an IP address and associated VLAN number.
Whitepaper Advancements And Economics Make Vdsl Ideal Finaldandreladson
Video demand is driving the need for broadband networks capable of 100Mbps or more. Most providers are building hybrid networks using fiber for backbones and existing copper for last-mile connections due to much lower costs compared to full fiber networks. New VDSL technologies can deliver high speeds over copper at a fraction of the cost of fiber while meeting demand. VDSL uses techniques like bonding and vectoring to support high performance over copper for the foreseeable future.
Track e the road from 2 d to 3d integration -synopsyschiportal
This document discusses the transition from 2D to 3D integrated circuit design. It provides a brief history of stacking and through-silicon vias. While 3D integration provides benefits like higher bandwidth and smaller footprint, there are also challenges to address like cost overhead, yield loss, and complex design tools/flows. Key issues discussed are the large number and placement of through-silicon vias, and their impact on performance, power, and yield through stress proximity effects. Overall the document outlines both the promise and challenges of 3D design.
The document discusses computer networks and communication. It defines key network concepts like transmission methods, network categories, protocols, and internet terms. It explains the basic elements of communication including senders, mediums, receivers, and messages. It also summarizes different network types like LANs, WANs, intranets, and the internet. Finally, it outlines the OSI model layers and their functions in network communication.
This document discusses different types of guided media, including twisted pair cable, coaxial cable, and fiber optic cable. It provides details on the characteristics of each type of cable, such as their uses, advantages, and disadvantages. Twisted pair cable is commonly used for short distance digital data transmission at speeds up to 9600 bits per second. Coaxial cable has higher bandwidth and can transmit signals over longer distances compared to twisted pair. Fiber optic cable has the highest bandwidth capability and is less susceptible to interference, but is the most expensive option.
Nowadays, mobile consumer electronics devices integrate various wireless interfaces like WIFI, Bluetooth, GPRS and GPS. Various approaches exist to protect the wireless interfaces against ESD stress. In recent years, researchers have focused on so‐called 'co‐design' techniques to solve both functional and protection constraints together which requires both RF and ESD design skills. However many IC designers still prefer to work with 'plug‐n‐play' protection concepts where the ESD clamps exhibit low parasitic capacitance, low series resistance and low leakage. This paper presents measurement results of 3 different SCR based protection approaches that exhibit high Q‐factor and low and stable parasitic capacitance over a broad voltage and frequency range. The clamps are used for protection of LNA circuits in 90nm and 40nm Low Power (LP) CMOS technologies.
Li-Fi or optical Wi-Fi is a new technology that uses visible light communication (VLC) to transmit data wirelessly using LED lights. It provides higher speeds than Wi-Fi and is more secure as light cannot pass through walls. Li-Fi was first demonstrated by German physicist Harald Hass and uses pulsing LED lights to transmit binary code for wireless internet access. It has advantages over Wi-Fi such as no interference from radio frequencies, higher speeds up to 10 Gbps, and lower power consumption. Li-Fi is being commercialized by companies and can be used in applications like wireless networks at home or in hospitals where RF signals are restricted.
The document provides a proposal for implementing a VSAT connectivity solution for internet access. It describes what VSAT is, its applications, advantages over terrestrial networks, and then provides two pricing options - one with shared bandwidth and one with dedicated bandwidth. Key details include installation and setup within 7 days, 6 months warranty, and payment terms of 80% on order and 20% on activation. Overall the proposal outlines a turnkey satellite-based internet solution using VSAT technology.
IRJET- Highway Navigation System using Light Fidelity TechnologyIRJET Journal
This paper proposes a smart highway navigation system using Li-Fi (Light Fidelity) technology. Li-Fi uses visible light communication to transmit data using LED lights at speeds greater than Wi-Fi. The system would install Li-Fi transmitters in streetlights that would send location and direction data to vehicles equipped with Li-Fi receivers. The receivers would display the navigation information on an LCD screen. This system could provide automatic navigation for travelers on highways without needing mobile networks or GPS. It was simulated using Proteus software and the prototype had transmitters with microcontrollers and high-intensity LEDs and receivers with LDR photo detectors connected to another microcontroller and LCD display.
Manufacturer and Supplier of ST/PC Fiber Optical Patch Cord, Distribution Patch Cord, ST/PC MM.SM Adapter, ST/PC SM Attenuator(Adapter Type And Connector Type), SC/PC/APC Fiber Optical Patch Cord and SC/PC/APC Loopback Patch Cord.
This document is a catalogue for Havells India Ltd's wire and cable products. It provides an overview of the company, which manufactures electrical power distribution and transmission equipment across India and other countries. The catalogue then describes Havells' manufacturing process for cables, including details on the conductor, insulation, screening, armouring, and testing. It also lists the advantages of PVC and XLPE insulated cables. Finally, it notes that Havells has received NABL accreditation for its testing laboratory to ensure quality evaluation of its wire and cable products.
Gleam Electric and Power Company was incepted in 2013 and is supplying, trading, distributing and wholesaling a diverse range of Electrical Power Cables & Wires. Our product range is regarded by our clients for being interesting and includes Power Cables, Electrical Cables and Copper Flexible Wires. These cables are known for being long lasting, perfect in terms of finish, resistant to wear & tear and non corrosive.
Specialization in offering the world class range of Communication Devices that are sourced from the most reliable vendors in the market. The diversified range includes Multimeter, Optical Test Equipment, Under Ground Utility Locator, Fiber Optic Passive Components, LCD Display, RF Test Equipment, Fusion Splicing Machine and Accessories and various others.
This document discusses inter-VLAN routing and configuring a router to route between VLANs. It describes using router subinterfaces to allow a single physical router interface to route traffic for multiple VLANs by assigning each subinterface its own IP address and VLAN encapsulation. The document also briefly mentions using a multilayer switch for inter-VLAN routing and revising VLAN and trunk configuration as prerequisites.
The document discusses the key topics and concepts for designing a hierarchical LAN network, including the 3-level model consisting of core, distribution, and access layers. It covers choosing switches for each layer based on required features like port density, speed, redundancy, and layer 3 routing capability. The document also mentions incorporating voice and video traffic using quality of service and the advantages of a converged network supporting multiple traffic types over a single infrastructure.
The document discusses VLAN Trunking Protocol (VTP), which allows VLAN configurations to be automatically propagated across multiple switches to reduce configuration errors and maintenance. VTP operates by defining a VTP domain where one switch acts as a server to send VLAN information to other client switches. It describes how VTP advertisements are sent and processed to update switches when VLANs are added or modified on the server. The roles of server, client, and transparent modes are also outlined.
The document discusses switches and Ethernet networking concepts. It covers how switches work by building a MAC address table to forward frames, the operation of 100/1000 Mbps Ethernet, and configuring basic switch security. It also reviews related topics like collision domains, broadcast domains, latency, congestion, and switch forwarding methods.
The document discusses the Spanning Tree Protocol (STP) which eliminates switching loops in a converged network. STP runs on switches by default and works by disabling redundant links to form a spanning tree topology with no loops. It uses a three step algorithm to choose a root bridge, select root and designated ports, and block redundant ports. Rapid STP and per-VLAN STP were developed to improve convergence times.
The document discusses VLANs (virtual local area networks) and their role in dividing a network into logical segments. VLANs allow users to be grouped by function rather than physical location, improving flexibility. VLANs are configured on switches using port-based assignments and trunk links allow traffic from multiple VLANs to travel between switches using tagging. The document provides examples of configuring, monitoring and troubleshooting VLANs on Cisco switches.
This document discusses inter-VLAN routing, including using a router to enable communication between devices on different VLANs, configuring inter-VLAN routing on a router, and troubleshooting common inter-VLAN connectivity issues. It explains that inter-VLAN routing requires a router or layer 3 switch to route traffic between VLANs and that a traditional method uses multiple router interfaces connected to separate VLANs, while router-on-a-stick uses router subinterfaces connected to a layer 2 switch, with each subinterface needing an IP address and associated VLAN number.
The document discusses WiMAX technology and architecture. It provides an overview of the IEEE 802.16 standard, operating frequencies, data rates, network components, and services supported. The key components of a WiMAX network include the subscriber stations, access service network with base stations, connectivity service network with AAA and DHCP servers, and network service provider layer which offers various applications and services to subscribers.
This document discusses wireless LANs (WLANs) and how they differ from traditional LANs. WLANs use radio waves instead of wires for transmission and thus can experience issues like coverage problems and interference that are not seen on wired networks. While WLANs and LANs both use CSMA to manage access to the shared medium, WLANs use CSMA/CA instead of CSMA/CD. The IEEE defines various 802.11 wireless standards that specify radio bands and frequencies used. The Wi-Fi Alliance certifies products to ensure interoperability between devices supporting different 802.11 standards.
This document summarizes network devices and concepts from a CCNA guide. It describes how repeaters, hubs, wireless access points, bridges, switches and routers segment networks and control traffic. It also defines Ethernet, Fast Ethernet and Gigabit Ethernet standards, and explains half and full-duplex communication modes. The summary provides an overview of common network devices and technologies for local area networks.
Wi-Fi uses radio waves to transmit data through the air according to the IEEE 802.11 standards. It allows computers and other devices to connect to the internet and each other wirelessly. The 802.11 standards include 802.11b, 802.11a, 802.11g, 802.11n, and 802.11ac which provide different speeds and capabilities. Wi-Fi networks use access points, wireless cards, and security protocols like WEP, WPA, and WPA2 to transmit data securely between devices over short ranges.
The document discusses the history and role of the Institute of Electrical and Electronics Engineers (IEEE). It describes how IEEE was formed through the merging of earlier organizations and how it is now the largest technical professional organization dedicated to advancing technology for humanity. IEEE develops a wide range of standards for various industries and technologies, including over 900 active standards, and holds hundreds of conferences annually.
This document provides an overview of switch operation and configuration. It discusses topics like Ethernet frame format, MAC address tables, collision and broadcast domains, latency, buffering methods, and the CLI of Cisco switches. The document is intended to remind readers about basic switching concepts covered in a CCNA curriculum.
Presented by Reshma M.R.
Wi-Fi, which stands for “Wireless Fidelity”, is a radio technology that networks computers so
they connect to each other and to the Internet without wires.
WiMAX, meaning Worldwide Interoperability for Microwave Access, is a
telecommunications technology that provides wireless transmission of data using a variety of
transmission modes, from point-to-point links to portable internet access
Bluetooth Reinvented. Smart connectivity in consumer devices: Bluetooth Low ...CSR
We sometime get chances to evangelise our businesses. In early 2013, Joe Decuir, from our Global Standards team, was appointed a Distinguished Lecturer by the IEEE Consumer Electronics Society. His talk is titled “Bluetooth Reinvented. Smart connectivity in consumer devices: Bluetooth Low Energy Standard and its Applications”. The first scheduled discussion was at the Bangalore Chapter last week, hosted by the India Institute of Sciences. Follow up visits are in discussion with IEEE CES chapters in Hong Kong, Shenzhen, Hsinchu, Seoul, Osaka and Tokyo.
Successful technical presentations have four elements: What is this? How does it work? What is it good for? Where can I learn more? The presenter wins if the audience comes away thinking that the topic deserves follow up attention. At least 150 people showed up for this presentation. The questions were fun. There were two demonstrations: a tracking demo (fixed by CSR India staff) and a Fitbit One.
Two awards were presented: for the presentation and a commemorative medal from IIS. The latter is now on display in the front office of CSR India.
There will also be a corresponding article submitted to the IEEE CES Magazine this year.
Congratulations to Joe!
Wireless Technologies
Presented by
Sean Shields
And
Gabriel Taveras
Definition
Term “Wireless” refers to all the communications sent and received without wires.
So Wireless Technology
Means a technology that use radio waves to transmit or receive data.
Wi-Fi
Bluetooth
Cellular
Wimax
TYPES OF
TECHNOLOGIES
INTRODUCTION:
Wireless Fidelity termed as Wi-Fi uses the IEEE 802.11 specification to create a wireless local-area network.
A Wi-Fi network basically consists of a wired connection to the Internet that leads to a wireless router for transmutation and receiving data from individual devices, connecting them not only to the outside world but also to each other.
HOW WIFI WORKS?
1. All devices use a wireless adapter to convert request into a radio signal and broadcasts it into the air.
2. The Wi-Fi device, or wireless router, picks up the signal and translates it back into its original form.
3. The router passes the request to the Internet using a hardwired connection.
4. The Internet returns the requested information to the router across the same connection.
5. The router converts the information into a radio signal and broadcasts it into the air.
6. The computer or cell phone's wireless adapter picks up the information and displays it on your screen
WIFI TOPOLOGIES
Wifi have following topologies
AP-based topology (Infrastructure Mode)
Peer-to-peer topology (Ad-hoc Mode)
Point-to-multipoint bridge topology
Wi Fi Network
Wireless Standards
802.11
In 1997, the Institute of Electrical and Electronics Engineers (IEEE) created the first WLAN standard. They called it 802.11 after the name of the group formed to oversee its development. Unfortunately, 802.11 only supported a maximum network bandwidth of 2 Mbps - too slow for most applications. For this reason, ordinary 802.11 wireless products are no longer manufactured.
Wireless Standards
802.11b
IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports bandwidth up to 11 Mbps, comparable to traditional Ethernet.
Wireless Standards
802.11a
Supports bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz. This higher frequency compared to 802.11b shortens the range of 802.11a networks. The higher frequency also means 802.11a signals have more difficulty penetrating walls and other obstructions.
Wireless Standards
802.11g
Attempts to combine the best of both 802.11a and 802.11b. 802.11g supports bandwidth up to 54 Mbps, and it uses the 2.4 Ghz frequency for greater range. 802.11g is backwards compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa.
Wireless Standards
802.11n
The newest IEEE standard in the Wi-Fi category is 802.11n.
802.11n connections support data rates of over 100 Mbps. 802.11n also offers somewhat better range over earlier Wi-Fi standards due to its increased signal.
This document analyzes the performance of Wi-Fi networks under three conditions: no fading, flat fading, and dispersive fading. It simulates these conditions using an IEEE 802.11a WLAN physical layer model in Matlab. The simulation measures packet error rate and bit rate as the signal-to-noise ratio and maximum Doppler shift are varied. With no fading, there is no packet error and bit rate increases with SNR. Under flat and dispersive fading, packet error and bit rates are affected differently based on the maximum Doppler shift. The best performance occurs under flat fading with a lower maximum Doppler shift of 100Hz.
This document discusses Ruckus Wireless enterprise Wi-Fi solutions. It notes that Wi-Fi devices are surpassing Ethernet devices in annual shipments. Ruckus technology includes adaptive antenna technology, adaptive meshing, and advanced security and quality of service features. The technology extends Wi-Fi range, improves performance and reliability, and avoids interference through techniques like BeamFlex adaptive antennas. Ruckus also provides centralized management, device identification and policies, and application recognition capabilities to support BYOD and a variety of other use cases.
Verilog Based Design and Simulation of MAC and PHY Layers for Zigbee Digital ...IJERA Editor
The past several years have witnessed a rapid development in the wireless network area. So far wireless networking has been focused on high-speed and long range applications. Zigbee technology was developed for a Wireless Personal Area Networks (WPAN), aimed at control and military applications with low data rate and low power consumption. Zigbee is a standard defines the set of communication protocols for low-data-rate short-range wireless networking. Zigbee-based wireless devices operate in 868 MHz, 915 MHz, and 2.4 GHz frequency bands. The maximum data rate is 250K bits per second. Zigbee is mainly for battery-powered applications where low data rate, low cost, and long battery life are main requirements. This paper explores Verilog design for various blocks in Zigbee Transmitter architecture for an acknowledgement frame. The word digital has made a dramatic impact on our society. Developments of digital solutions have been possible due to good digital system design and modeling techniques. Further developments have been made and introduced VLSI in order to reduce size of the architecture, to improve speed of operation, improvements in predictability of the circuit behavior. Digital Zigbee Transmitter comprises of Cyclic Redundancy Check, Bit-to-Symbol block, Symbol-to-chip block, Modulator and Pulse shaping block. The work here is to show how we can design Zigbee transmitter with its specifications by using Verilog with less number of slices and Look up tables (LUTs).
The document outlines potential use cases for light communications (LC), including vehicle-to-vehicle communications, manufacturing and harsh environments, power plants, and nuclear facilities. It notes that LC could help reduce interference in vehicle networks and provide a safe and reliable wireless option in environments prone to electromagnetic interference, such as power plants. The document also discusses challenges with using traditional wireless in nuclear facilities and how an LC-based mesh network using LED lights could help address issues around interference and installation costs.
This seminar report discusses wireless ad-hoc networks. It begins with an introduction to wireless ad-hoc networks and how to set up a computer-to-computer network without infrastructure. Some key technical aspects are discussed such as medium access control, routing protocols, and security challenges. Simulation of wireless ad-hoc networks is also covered. The report concludes that while wireless ad-hoc networks provide flexibility, capacity is limited as more users are added to the network. Designing for smaller networks or local connectivity may improve acceptance.
This document provides an overview of wireless communication and networking. It defines wireless communication and discusses wireless network topologies and integration with wired networks. It describes the IEEE 802.11 wireless standards including 802.11a, 802.11b, 802.11g and 802.11n. It also discusses wireless networking devices such as access points, wireless LAN controllers, and bridges. Finally, it covers common wireless security measures including SSID hiding, MAC address filtering, static IP addressing, 802.1X authentication, WEP, WPA, and WPA2 encryption.
This document provides an overview of Wi-Fi technology. It defines Wi-Fi as a wireless networking standard based on the IEEE 802.11 specifications. It outlines the various 802.11 standards including 802.11b, 802.11a, 802.11g, and 802.11n, and describes their characteristics such as speed and frequency band. It also discusses Wi-Fi network elements, channels and association, mobility, network topologies of infrastructure and ad-hoc modes, and long-range Wi-Fi applications. Security and limitations of Wi-Fi are also mentioned.
This document provides an overview of wide area network (WAN) concepts and technologies. It discusses the purpose of WANs in connecting local area networks, common WAN topologies, and how WANs relate to the OSI model. The document also examines various WAN technologies including dedicated circuits, Frame Relay, ATM, Ethernet, MPLS, and broadband options. Key considerations for selecting a WAN technology include whether to use a private WAN infrastructure with a service provider or a public WAN over the internet using VPNs.
Yousaf Sahota submitted a document about Wi-Fi networks that discusses the key elements, topologies, advantages, and limitations. It introduces Wi-Fi as a wireless standard that uses access points and Wi-Fi cards to connect devices without wires. The document describes peer-to-peer and infrastructure topologies and notes advantages like mobility, ease of installation, and cost while limitations include interference and limited range. It concludes that Wi-Fi provides a simple, cost-effective way to connect to the internet wirelessly.
Final exam ccna exploration 3 lan switching and wirelesskratos2424
The document is a practice exam for the CCNA Exploration 3 LAN Switching and Wireless final exam. It contains 25 multiple choice questions covering topics such as IP addressing, switch configuration, VLANs, trunking, STP, and inter-VLAN routing.
Ch6 ccna exploration 3 lan switching and wirelesskratos2424
This document provides answers to questions about configuring router-on-a-stick inter-VLAN routing. Key steps include creating VLANs on the switch and router, configuring subinterfaces on the router matching the VLAN IDs, and using a trunk link between the switch and router. The router responds to ARP requests with the MAC address of the physical interface when using router-on-a-stick.
Ch7 ccna exploration 3 lan switching and wirelesskratos2424
This document contains 21 multiple choice questions about wireless networking concepts such as 802.11 standards, wireless security protocols, wireless network design processes, and functions of wireless access points. The questions cover topics like factors influencing adoption of 802.11 standards, statements about wireless security, methods for configuring a new wireless network, identifying settings used to configure the wireless network name, characteristics of wireless security, steps for addressing poor wireless performance in an area, common devices incorporated in wireless routers, wireless access methods, importance of security in wireless networks, compatibility of wireless standards, statements about wireless network security risks, the network design process of identifying access point locations, wireless security features like MAC address filtering, signals transmitted to discover available wireless networks, reasons
Ch5 ccna exploration 3 lan swtching and wirelesskratos2424
The document contains a 20 question CCNA Exploration 3 Chapter 5 Exam with multiple choice answers regarding Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP). The questions cover topics such as PortFast, STP states, RSTP roles, the convergence process, comparisons between STP and RSTP, BPDU content and usage, root bridge selection, and edge port behavior.
Ch4 ccna exploration 3 lan switching and wirelesskratos2424
VTP dynamically communicates VLAN changes to all switches in the same VTP domain. Switches must be configured with the same VTP domain name, mode, revision number, and version number to participate in the same VTP domain and synchronize VLAN information. A switch with a lower revision number will update to the higher revision number, synchronizing VLAN configurations.
Ch3 ccna exploration 3 lan switching and wirelesskratos2424
This document contains a CCNA exam with multiple choice questions about VLANs and trunking. Some key points:
- VLANs improve network security by isolating users and reducing broadcast storms. Trunking allows multiple VLANs to cross a link.
- In a default switch configuration, all ports are members of VLAN1.
- For trunking to occur, both switch ports must be configured consistently (e.g. with trunk mode on).
- VLAN tags are only added on trunk links that carry multiple VLANs between switches.
- Non-default VLANs must use extended range numbers like 20-30. VLANs can be configured in VLAN database or global config mode.
Ch2 ccna exploration 3 lan switching and wirelesskratos2424
When a collision occurs using CSMA/CD, hosts return to listen-before-transmit mode after the backoff period expires. No collisions will occur on a link administratively configured for full-duplex. With an empty MAC table, SW1 will flood the frame from PC_A to PC_C on all ports except the originating port. When receiving a frame with an unknown source MAC, the switch will map the source to the receiving port. With default configurations, workstations B and C will capture the frame from workstation A.
Ccna exploration 3 lan switching and wirelesskratos2424
This document contains 20 multiple choice questions about Cisco's hierarchical network model and related networking concepts. The questions cover topics like the different layers of the model (core, distribution, access), features supported at each layer like QoS and link aggregation, and technologies like VLANs, link aggregation, and switch characteristics.
1. Wireless
CCNA Exploration Semester 3
Chapter 7
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2. Topics
Components and basic operation of wireless
LANs
Basic WLAN security
Configure and verify basic wireless LAN
access
Troubleshoot wireless client access
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3. Semester 3
LAN Design
Basic Switch Wireless
Concepts
VLANs STP
VTP Inter-VLAN
routing
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4. Wireless advantages
Stay in contact while travelling.
Move workstation within building without
moving cables.
In new building, save cost of cabling the
whole building – just some cables needed.
Use a variety of wireless devices.
Can link to cabled network.
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5. Wireless problems
Interference
Signal strength, blind spots
Security – anyone with receiver within range
can pick up signals
Regulations differ in different countries
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6. Standards
PAN LAN MAN WAN
Standards Bluetooth 802.11 802.11 GSM
802.15.3 802.16 CDMA
802.20 Satellite
Speed < 1 Mbps 11-54 10 – 100+ 10 Kbps –
Mbps Mbps 2 Mbps
Range Short medium Medium- Long
long
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7. Wireless and Ethernet
Wireless workstations connect to cabled
Ethernet network via an access point (AP).
Collisions can occur both with Ethernet and
with wireless.
Ethernet detects and recovers (CSMA/CD)
Wireless uses collision avoidance.
Frame format is different.
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8. 802.11a
Introduced 1999, not compatible with 802.11b
OFDM modulation (faster, up to 54Mbps)
More costly than 802.11b
5 GHz band.
Smaller antennas, less interference
Poorer range, absorbed more by walls etc.
Not allowed in some countries.
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9. 802.11b
Introduced 1999, not compatible with 802.11a
DSSS modulation, slower, 1, 2, 5.5, 11 Mbps
Cheaper than 802.11a
2.4 GHz band.
More interference as many appliances use
this band
Longer range, less easily obstructed.
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10. 802.11g
Introduced 2003
Compatible with 802.11b
DSSS modulation, to 11 Mbps or OFDM to
54 Mbps
2.4 GHz band.
More interference as many appliances use
this band
Longer range, less easily obstructed.
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11. 802.11n
Expected Sept 2008, in draft now.
May use both 2.4 and 5 GHz band
MIMO-OFDM Splits high data rate stream
into several low data rate streams, transmits
simultaneously using multiple antennae.
Possibly up to 248 Mbps with 2 streams
Longer range, 70 metres
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12. Organisations
ITU-R allocates RF spectrum bands and
satellite orbits
IEEE develops and maintains 802 standards
for LANs and MANs including wireless
modulation
Wi-Fi Alliance certifies that vendors keep to
standards and industry norms so that devices
can operate together
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13. Wireless NIC
Needed to connect a device to an access
point.
Laptops used to have PCMCIA cards. Some
still do, but now the NIC is usually built in.
Desktops can have expansion cards
installed, or they can use a USB device.
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14. Access point, shared medium
Access point acts like a hub (not switch)
Wireless is a shared medium
802.11 uses CSMA/CA
Devices detect activity on the medium, send
signals if all is clear.
Signal is acknowledged if it is received
Attenuation limits distance of client from
access point.
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15. Hidden nodes
Iftwo stations cannot sense
each others’ signals then they
may transmit at the same time
and have a collision.
Request to send/clear to send (RTS/CTS)
avoids this.
Station requests the medium, access point
allocates it for long enough to complete the
transmission.
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16. Wireless router
Commonly used for Internet access
Acts as router, Ethernet switch and wireless
access point.
Configure for mode 802.11a, b, g, or n
Configure shared service set identifier (SSID)
to identify network
Select channel within 2.4GHz band. Adjacent
access points need non-overlapping
channels.
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17. Ad hoc topology
No access point
Peer to peer
Negotiate parameters
Independent basic
service set
Area covered is basic
service area (BSA).
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18. Basic service set topology
One access point
Access point manages
parameters for clients
Infrastructure mode
Area covered is basic service
area (BSA).
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19. Extended service set topology
More than one access
point
Access point manages
parameters for clients
Infrastructure mode
Area covered is
extended service area
(ESA).
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20. Beacon and probe
Access point may send out a beacon at
regular intervals for clients to detect.
Client sends a probe specifying the SSID and
bit rates supported. Access point responds.
Client can send probe with no SSID to look
for any network. Access point may be
configured to respond, or not.
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21. Authentication
Clientrequests authentication.
Access point responds.
802.11 had two authentication mechanisms.
NULL (Open Authentication) does not give
privacy. Wired Equivalency Protection (WEP)
uses a shared key.
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22. Association
Request from client and response.
Finalizes security options
Finalizes bit rate options
Sets up data link
Client learns the access point MAC address
(BSSID)
Access point maps a logical port known as
the association identifier (AID) to the WLAN
client.
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23. Placing access points
Above obstructions.
At least 3 feet from metal obstructions.
Vertically and high up.
In locations where users will work.
But not too close to people.
Work out the coverage for each AP.
Allow enough overlap.
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24. Security threats
War drivers look for an unsecured network
that will provide Internet access.
Hackers (Crackers) enter systems to steal
data or cause harm. They can often get past
weak security.
Employees may install rogue access points
without permission and without implementing
the necessary security.
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25. Man in the middle
Attacker modifies the NIC of a laptop with
special software so that it accepts all traffic,
not just traffic addressed to it.
Uses packet sniffing software, such as
Wireshark, to observe a client station
connecting to an access point. Detects
names, IP addresses, ID and the challenge
and associate response.
Can then monitor network.
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26. Denial of service
Use common devices to create interference.
(cordless phone, microwave, baby monitor)
Flood the network with clear-to-send (CTS)
messages. Clients then send simultaneously
and cause a constant stream of collisions.
Send a series of disassociate commands so
that clients repeatedly disconnect then try to
reassociate.
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27. 802.11 original authentication
Open authentication – no privacy or security
“Authenticate me.” “All right.”
WEP shared key authentication – weak
encryption algorithm could be cracked. 32 bit
key had to be entered by hand. Prone to error
and not easily scalable.
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28. Authentication developments
Vendors created their own security systems
Wi-Fi Alliance developed WiFi Protected
Access (WPA) security method.
802.11i standard introduced - similar to the
Wi-Fi Alliance WPA2 standard.
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29. TKIP and AES encryption
Temporal Key Integrity Protocol (TKIP) encryption
mechanism is certified as WPA by Wi-Fi Alliance.
TKIP uses the original encryption algorithm used by
WEP but addresses its weaknesses.
TKIP encrypts the Layer 2 payload and carries out a
message integrity check to detect tampering.
Advanced Encryption Standard (AES) encryption
mechanism is certified as WPA2. Has additional
features.
AES is the preferred method.
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30. Configuring Access Point
1. Check wired operation: DHCP, Internet access
2. Install access point
3. Configure access point without security
4. Install one wireless client without security
5. Check wireless network operation
6. Configure security
7. Check wireless network operation
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31. Basic Wireless Settings
Network Mode – Lets you choose the right
mode for your devices. B, G, N, mixed or BG
mixed. You can disable wireless operation.
Network Name (SSID) – should be changed
from the default. Must be the same for all
devices on the network.
SSID broadcast can be enabled or disabled.
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32. More Basic Wireless Settings
Radio Band –
For Wireless-N devices only, select Wide - 40MHz
Channel.
For Wireless-G and Wireless-B only, select
Standard - 20MHz Channel.
For mixed devices, keep the default Auto.
Wide Channel - If you selected Wide for the
Radio Band, Select a channel from the drop-
down menu.
Standard Channel - Select the channel.
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33. Security
Choose PSK2 (WPA2 or IEEE 802.11i) if all
client devices are able to use it.
If some older devices do not support WPA2
then choose the best security mode that is
supported by all devices.
Encryption – AES is stronger than TKIP. Use
AES with WPA2.
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34. Configure the client
Choose the network to connect to.
Enter the SSID
Choose the authentication method
Choose the encryption method
Enter the network key.
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35. Troubleshooting
Generally start with the physical layer and
then move up.
Eliminate the client PC as the source of
trouble before checking the rest of the
network.
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36. Troubleshooting – no connectivity
Check that the PC has an IP address.
Try connecting the PC to the wired network
and ping a known address
Try a different wireless NIC. Reload drivers
as necessary.
Check the security mode and encryption
settings on the client. Do they match the
access point?
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37. Troubleshooting – poor connection
Check distance to access point
Check the channel settings on the client.
Check for devices that might be causing
interference (cordless phone, microwave
oven etc).
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38. Troubleshooting – looking wider
Are all devices in place?
Are they all powered on?
Are wired links working correctly?
Is there a neighbouring access point using an
overlapping wave band?
Are access points badly placed?
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39. The End
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