1 / 27

Wi-Fi Technology

Wi-Fi Technology. ARTI J JANSARI M.E.(C.S.E.):-1 ST (E.C.). CONTENTS. Introduction Wi-Fi Technologies Wi-Fi Architecture Wi-Fi Network Elements How a Wi-Fi Network Works Wi-Fi Network Topologies Applications of Wi-Fi

twyla
Download Presentation

Wi-Fi Technology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Wi-Fi Technology ARTI J JANSARI M.E.(C.S.E.):-1ST (E.C.)

  2. CONTENTS • Introduction • Wi-Fi Technologies • Wi-Fi Architecture • Wi-Fi Network Elements • How a Wi-Fi Network Works • Wi-Fi Network Topologies • Applications of Wi-Fi • Wi-Fi Security • Advantages/ Disadvantages of Wi-Fi

  3. INTRODUCTION • Wireless Technology is an alternative to Wired Technology , which is commonly used, for connecting devices in wireless mode. • Wi-Fi (Wireless Fidelity) is a generic term that refers to the IEEE 802.11 communications standard for Wireless Local Area Networks (WLANs). • Wi-Fi Network connect computers to each other, to the internet and to the wired network.

  4. The Wi-Fi Technology Wi-Fi Networks use Radio Technologies to transmit & receive data at high speed . The name 802.1 comes from the IEEE committee that standardized it. • IEEE 802.11b • IEEE 802.11a • IEEE 802.11g

  5. IEEE 802.11b • Appear in late 1999 • Operates at 2.4GHz radio spectrum • 11 Mbps (theoretical speed) - within 30 m Range • 4-6 Mbps (actual speed) • 100 -150 feet range • Most popular, Least Expensive • Interference from mobile phones and Bluetooth devices which can reduce the transmission speed.

  6. IEEE 802.11a • Introduced in 2001 • Operates at 5 GHz (less popular) • 54 Mbps (theoretical speed) • 15-20 Mbps (Actual speed) • 50-75 feet range • More expensive • Not compatible with 802.11b

  7. IEEE 802.11g • Introduced in 2003 • Combine the feature of both standards (a,b) • 100-150 feet range • 54 Mbps Speed • 2.4 GHz radio frequencies • Compatible with ‘b’ • Use OFDM Technology

  8. 802.11 Physical Layer There are three sub layers in physical layer: • Direct Sequence Spread Spectrum (DSSS) • Frequency Hoping Spread Spectrum (FHSS) • Diffused Infrared (DFIR) - Wide angle

  9. DSSS • Direct sequence signaling technique divides the 2.4 GHz band into 11 22-MHz channels. Adjacent channels overlap one another partially, with three of the 11 being completely non-overlapping. Data is sent across one of these 22 MHz channels without hopping to other channels.

  10. IEEE 802.11 Data Link Layer The data link layer consists of two sublayers : • Logical Link Control (LLC) • Media Access Control (MAC). 802.11 uses the same 802.2 LLC and 48-bit addressing as other 802 LANs, allowing for very simple bridging from wireless to IEEE wired networks, but the MAC is unique to WLANs.

  11. Elements of a WI-FI Network • Access Point (AP) - The AP is a wireless LAN transceiver or “base station” that can connect one or many wireless devices simultaneously to the Internet. • Wi-Fi cards - They accept the wireless signal and relay information. They can be internal and external. (e.g PCMCIA Card for Laptop and PCI Card for Desktop PC) • Safeguards - Firewalls and anti-virus software protect networks from uninvited users and keep information secure.

  12. How a Wi-Fi Network Works • Basic concept is same as Walkie talkies. • A Wi-Fi hotspot is created by installing an access point to an internet connection. • An access point acts as a base station. • When Wi-Fi enabled device encounters a hotspot the device can then connect to that network wirelessly. • A single access point can support up to 30 users and can function within a range of 100 – 150 feet indoors and up to 300 feet outdoors. • Many access points can be connected to each other via Ethernet cables to create a single large network.

  13. Wi-Fi Network Topologies • AP-based topology (Infrastructure Mode) • Peer-to-peer topology (Ad-hoc Mode) • Point-to-multipoint bridge topology

  14. AP-based topology • The client communicate through Access Point. • BSA-RF coverage provided by an AP. • ESA-It consists of 2 or more BSA. • ESA cell includes 10-15% overlap to allow roaming.

  15. Peer-to-peer TOPOLOGY • AP is not required. • Client devices within a cell can communicate directly with each other. • It is useful for setting up of a wireless network quickly and easily.

  16. Point-to-multipoint bridge TOPOLOGY This is used to connect a LAN in one building to a LANs in other buildings even if the buildings are miles apart.These conditions receive a clear line of sight between buildings. The line-of-sight range varies based on the type of wireless bridge and antenna used as well as the environmental conditions.

  17. Wi-Fi CONFIGURATION

  18. Wi-Fi CONFIGURATION

  19. Wi-Fi CONFIGARATION

  20. Wi-Fi APPLICATION • Home • Small Businesses or SOHO • Large Corporations & Campuses • Health Care • Wireless ISP (WISP) • Travellers

  21. Wi-Fi Security The requirements for Wi-Fi network security can be broken down into two primary components: • Authentication • User Authentication • Server Authentication • Privacy

  22. Wi-Fi Security Techniques • Service Set Identifier (SSID) • Wired Equivalent Privacy (WEP) • 802.1X Access Control • Wireless Protected Access (WPA) • IEEE 802.11i

  23. ADVANTAGES • Mobility • Ease of Installation • Flexibility • Cost • Reliability • Security • Use unlicensed part of the radio spectrum • Roaming • Speed

  24. LIMITATION • Interference • Degradation in performance • High power consumption • Limited range

  25. CONCLUSION • For now Wi-Fi provides broad band internet access to specially outfitted PCs and Laptops. But in future may be hotspots be wireless. • By Wi-Fi our time and money are saved. • The technologies have help Wi-Fi “Hotspots are becoming more popular throught urban envirnment.”

  26. REFERENCE • www.Wi-Fitechnology.com • www.webopedia.com • www.wavewireless.com

  27. THANK YOU

More Related