tailieunhanh - WLAN and IEEE 802.11 Security

WLAN technologies are becoming increasingly popular, and promise to be the platform for many future applications: Home Entertainment Networking Example WLAN/WPAN Technologies: IEEE | WLAN and IEEE Security Agenda Intro to WLAN Security mechanisms in IEEE Attacks on Summary Wireless LAN Technologies WLAN technologies are becoming increasingly popular, and promise to be the platform for many future applications: Home Entertainment Networking Example WLAN/WPAN Technologies: IEEE Bluetooth WLAN End User Forecast (millions) Bluetooth Cable replacement Self-forming PANs (Personal Area Networks) Freq: GHz band Power 1mw to 100 mw Mode : FHSS Range: 40-50 Feet Data Rate: Approx 400 Kbps Security better than Wi-Fi but not MUCH of a concern. We will not focus on Bluetooth security in this talk. IEEE Wireless Networks Speeds of upto 54 Mb/s Operating Range: 10-100m indoors, 300m outdoors Power Output Limited to 1 Watt in . Frequency Hopping (FHSS), Direct Sequence & Infrared (IrDA) (– Networks are NOT compatible with each other) Uses unlicensed GHz band ( ,5 GHz) Provide wireless Ethernet for wired networks WLAN . | WLAN and IEEE Security Agenda Intro to WLAN Security mechanisms in IEEE Attacks on Summary Wireless LAN Technologies WLAN technologies are becoming increasingly popular, and promise to be the platform for many future applications: Home Entertainment Networking Example WLAN/WPAN Technologies: IEEE Bluetooth WLAN End User Forecast (millions) Bluetooth Cable replacement Self-forming PANs (Personal Area Networks) Freq: GHz band Power 1mw to 100 mw Mode : FHSS Range: 40-50 Feet Data Rate: Approx 400 Kbps Security better than Wi-Fi but not MUCH of a concern. We will not focus on Bluetooth security in this talk. IEEE Wireless Networks Speeds of upto 54 Mb/s Operating Range: 10-100m indoors, 300m outdoors Power Output Limited to 1 Watt in . Frequency Hopping (FHSS), Direct Sequence & Infrared (IrDA) (– Networks are NOT compatible with each other) Uses unlicensed GHz band ( ,5 GHz) Provide wireless Ethernet for wired networks WLAN Components More about WLAN Modes of Operation Ad Hoc mode (Independent Basic Service Set - IBSS) Infrastructure mode (Basic Service Set - BSS) Ad-Hoc mode Laptop users wishing to share files could set up an ad-hoc network using compatible NICs and share files without need for external media. Client A Client B Client C Infrastructure mode In this mode the clients communicate via a central station called Access Point (AP) which acts as an ethernet bridge and forwards the communication onto the appropriate network, either the wired or the wireless network. Client A Access point Client B WLAN Security – Problem !! There is no physical link between the nodes of a wireless network, the nodes transmit over the air and hence anyone within the radio range can eavesdrop on the communication. So conventional security measures that apply to a wired network do not work in this case. Internal network protected Wireless Access Point Valid User Access Only IEEE Basic Security Mechanisms .