Wi-Fi

1
Wi-Fi

• Mark Faggiano
• GBA 576

2
Purpose of the Project

• I hear Wi-Fi, WLAN, 802.11 everywhere
• What does it all mean?

3
Whats in a Name?

• Wi-Fi is
• Short for Wireless Fidelity
• Popular Term for Wireless LAN (WLAN)
• Also known as 802.11b

4
What is 802.11?

• 802.11 is
• A related group of specifications for WLANs
  developed by the Institute of Electrical and
  Electronic Engineers (IEEE)
• Currently, there are four different
  specifications in this group 802.11, 802.11a,
  802.11b, 802.11g

5
What does Wi-Fi Do?

• Wi-Fi
• Works a lot like a cell phone.
• Allows computers to send and receive data to each
  other anywhere within the range of a base
  station.
• Works without the use of a traditional
  infrastructure like cable and wires

6
Two Modes to Choose From

• Wi-Fi can be implemented in an
• Ad-hoc or Independent Basic Service Set
• Infrastructure or Basic Service Set

7
Ad-hoc Mode

• Peer-to-peer network (i.e., one computer is
  connected with another)

8
Infrastructure Mode

• Each wireless client computer deals with an
  access point via a radio link (i.e., a NIC card).
• The access point connects to the Ethernet
  enterprise network using a standard Ethernet
  cable, and provides the wireless client computer
  with access to the wired Ethernet network.
• Much more commonplace because access points are
  cheaper nowadays and a lot easier to set up.

9
Who Cares?

• The benefits to Wi-Fi include
• Cost
• Ease of Use
• Out-of-the-Box solutions
• Increased Adoption
• Starbucks
• Cities with wirelessaccess points

10
Here to Stay?

• 20 percent of large companies currently have
  wireless LANs in addition to their existing wired
  networks
• Estimated that 50 percent of U.S. companies will
  use the technology by 2003
• Sales of wireless network cards and access points
  to grow from 1.9 billion in 2001 to 5.2 billion
  in 2005

11
Wi-Fi and Security

• Security is an issue because
• Adoption was the goal
• Access points are usually behind firewall
• Existing security measures are inadequate

12
Existing Security

• Built-in security is called Wireless Equivalent
  Privacy (WEP).
• Two levels commonly available
• 64-bit encryption and 128-bit encryption
• Experts disagree if this security is enough.
  Regardless of what experts believe about either
  level of security in WEP, almost all believe that
  ignoring both of the built-in options is a huge
  mistake.
• AirSnort can crack the encryption by listening
  to the Wi-Fi networks traffic for a considerably
  short period of time

13
Security Study

• Tools Needed
• NetStumbler (shareware)
• Identifies 802.11b signals as it logs the MAC
  address of the access point, the network name,
  SSID, manufacturer, channel that the signal was
  heard on, WEP enabled (Yes or No), signal
  strength, signal to noise ratio, and other
  various flags. In addition, latitude and
  longitude data points are recorded if the access
  point emits standard GPS data.
• Antenna
• Detects the signals.
• Can be purchased from 60 to 130.

14
Security Study (cont)

• Methodology
• Writers checked several locations around the
  country (New York City, Jersey City, New England,
  and Silicon Valley).
• Locations were checked by either driving down a
  street populated by multiple businesses or by
  simply sitting on top of a building (as was the
  case in New York City)

15
Security Study (cont)

• Results
• Over 800 access points detected
• Some as far away as 6 blocks
• Less than 40 percent WEP-enabled
• Several attempts to gain access to networks were
  successful

16
Security Options

• VPN (Virtual Private Networks)
• Creates a secure virtual tunnel from the
  end-users computer through the end-users access
  point, though the Internet, all the way to a
  corporations servers and systems
• MAC (media Access Control) Filtering
• Accept only certain MAC addresses and filter out
  all others
• RADIUS
• A user name and password scheme that enables only
  approved users to access the network it does not
  affect or encrypt data
• Kerberos
• Network authentication system based on key
  distribution

17
Questions