SECURING WIRELESS LANS PRESENTED BY VICTOR C. NWALA CS555 Department of Computer Science Old Dominion University

What is a Wireless LAN A wireless local area network (WLAN) links two or more devices using some wireless distribution method (typically spread spectrum or OFDM radio), and usually providing a connection through an access point to the wider Internet. This gives users the mobility to move around within a local coverage area and still be connected to the network.

Basic Structure of A wireless LAN (Diagram from creatively.com)

Components of A Wireless LAN Access Point or Wireless Router Wireless Network Cards Wireless Bridges Broadband Modem

How does Wireless LAN work Wireless LAN uses a radio frequency, a frequency within the electromagnetic spectrum associated with radio wave propagation. When a radio frequency current is supplied to an antenna, an electromagnetic field is created which is able to propagate through space. With the aid of a WLAN access point, you can obtain access to the local network and to the Internet.

What could Possibly go wrong Deceptive Access Points Denial of Service Passive Capturing/Eavesdropping Illicit Entry

How can A WLAN be Secured To secure your wireless LAN, one must employ data encryption technology. There are also common best practices to be employed by users to secure their wireless LANS.

BASIC DATA ENCRYPTION TECHNIQUES AVAILABLE Wired Equivalent Privacy (WEP) Wi-Fi Protected Access (WPA) Wi-Fi Protected Access version 2 (WPA2) What is WEP? It is the original encryption protocol developed for wireless networks. WEP was created to provide the same level of security as wired networks.

Loop Holes in WEP Passive attacks used to decrypt packets based on statistical analysis. Active attack to inject new packets from unauthorized mobile stations, based on known plaintext message. Active attacks to decrypt packets, based on tricking the access point. Dictionary-building attack that, after analysis of about a days worth of traffic, this allows real-time automated decryption of all packets.

What is WPA WPA ( Wi Fi protected access) is a security certification for wireless computers that is designed to provide significantly stronger wireless data encryption than WEP, but they use the same hardware as the one of WEP. The devise software is just simply updated to WPA.

Is WPA Secure? WPA itself is reasonably secure. The passphrase can only be broken through brute force, so its only prone to hacking if you chose a weak single-word passphrase. It was never actually meant as a standard but just a quick fix until WPA2 became available. It uses TKIP, two know attacks against TKIP are Beck-Tews attack Ohigashi-Morii attack The only known attack against WPA is brute forcing the WPA key.

What is WPA2 WPA2 is a second, newer version of wireless protected access (WPA)security and access control technology for wireless networking. It replaces TKIP with CCMP and fixes the security issues of WPA So far it is the best wi fi protection mechanism from the THREE listed.

BEST PRACTICES IN SECURING WLANS Administrator Username and Password should be changed Immediately. Your WLAN identity should not be broadcast. Use WPA2 encryption to secure communication between your hosts and your wireless access point. Configure your wireless access point to accept only Mac Addresses of computers you own. Position your wireless router to reduce leakage. Turn off your wireless network when you are not using it for a long period of time.