WiFi Security

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Wi-Fi Security

• Securing your home network

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What is Wi-Fi?

• IEEE 802.11 or Wi-Fi denotes a set of wireless
  standards developed by the IEEE LAN/MAN Standards
  Committee.
• Trivia name comes from working group 11 of the
  IEEE.
• Wi-Fi uses radio frequency (RF) to establish a
  network connection.
• 802.11b and 802.11g standards use the 2.4 GHz
  band.
• 802.11b and 802.11g equipment can incur
  interference from microwave ovens, cordless
  phones, and other appliances using the same 2.4
  GHz band.

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Wi-Fi Speeds

• 802.11 1 and 2 Mbps
• 802.11a 20 Mbps
• 802.11b 11 Mbps, will scale back to 5.5, 2, 1
• 802.11e Super G 108Mbps
• Does it really matter for Internet?

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How it transmits

• Ethernet uses CSMA/CD
• carrier sense multiple access with collision
  detection
• Ethernet waits to see if the wire is idle, then
  sends. If a collision is detected, it resends.
• Wi-FI uses carrier sense multiple access protocol
  with collision avoidance (CSMA/CA).
• The base station polls nodes to see if they have
  anything to send much overhead in controlling
  transmission.
• The protocol itself is different than Ethernet,
  hence performance and reliability differ.

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Why Secure your Wi-Fi?

• Why secure it?
• Banking and sensitive information.
• Identity theft.
• Wireless cracking of your home PCs.
• Basic privacy.
• Prevent sharing of your Internet connection.
• How easy is it to snif unsecured Wi-Fi?
• Very, very easy use a wireless protocol analyzer
  to see all information.

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Securing your Wi-Fi

• Use WEP or WPA to encrypt data.
• Wired Equivalency Privacy
• Wi-Fi Protected Access
• Can be cracked, but difficult. WPA is stronger.
• Both work at Layer 2.
• WEP is analogous to locking your front door
  handle, whereas WPA is installing a good bolt
  lock. (Neither will deter a sufficiently
  motivated intruder!)
• WPA2 provides government grade security by
  implementing the National Institute of Standards
  and Technology (NIST) FIPS 140-2 compliant AES
  encryption algorithm.

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What's wrong with WEP?

• http//www.wi-fiplanet.com/tutorials/article.php/1
  368661
• WEP has been part of the 802.11 standard since
  initial ratification in September 1999. At that
  time, the 802.11 committee was aware of some WEP
  limitations however, WEP was the best choice to
  ensure efficient implementations worldwide.
  Nevertheless, WEP has undergone much scrutiny and
  criticism over the past couple years.
• WEP is vulnerable because of relatively short IVs
  and keys that remain static. The issues with WEP
  don't really have much to do with the RC4
  encryption algorithm. With only 24 bits, WEP
  eventually uses the same IV for different data
  packets. For a large busy network, this
  reoccurrence of IVs can happen within an hour or
  so. This results in the transmission of frames
  having keystreams that are too similar. If a
  hacker collects enough frames based on the same
  IV, the individual can determine the shared
  values among them, i.e., the keystream or the
  shared secret key. This of course leads to the
  hacker decrypting any of the 802.11 frames.

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Securing your Wi-Fi

• Use WPA or WEP for encryption.
• Use a MAC address filter. (Questionable)
• Change the default password on your router.
• Change your SSID or network name to something
  that doesnt identify you personally.
• Secure the files on your PCs by using good
  passwords, etc.
• Nothing will deter a sufficiently motivated
  cracker or intruder. Keep in mind that nothing is
  100 secure!

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Lets secure our Wi-Fi!

• Demo!