Wi-Fi Technology

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Wi-Fi Technology
PRESENTED BY- PRIYA AGRAWAL

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Agenda

• Introduction
• Wi-Fi Technologies
• Wi-Fi Network Elements
• How a Wi-Fi Network Works
• Wi-Fi Network Topologies
• Wi-Fi Configurations
• Applications of Wi-Fi
• Wi-Fi Security
• Advantages/ Disadvantages of Wi-Fi

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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.

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The Wi-Fi Technology

• Wi-Fi Networks use Radio Technologies to
  transmit receive data at high speed
• IEEE 802.11b
• IEEE 802.11a
• IEEE 802.11g

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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.

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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.

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Wi-Fi Network Topologies

• AP-based topology
• Peer-to-peer topology
• Point-to-multipoint bridge topology

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AP-based topology

• The client communicate through Access Point.

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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.

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Point-to-multipoint bridge topology
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Wi-Fi Configurations
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Wi-Fi Configurations
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Wi-Fi Configurations
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SECURITY THREATS

1. Attacker spoofes a disassociate message from the
   victim
2. The victim starts to look for a new access point,
   and the attacker advertises his own AP on a
   different channel, using the real APs MAC
   address
3. The attacker connects to the real AP using
   victims MAC address

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Wi-Fi Security

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

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Wi-Fi Applications

• Home
• Small Businesses or SOHO
• Large Corporations Campuses
• Health Care
• Wireless ISP (WISP)
• Travellers

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Advantages

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

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Limitations

• Interference
• Degradation in performance
• High power consumption
• Limited range