Wireless Security

Traditional method A computer with network card a cable connecting network card and the network

Wireless technology at home Infrared (IR) or Radio transmission e.g. remote control, cordless computer keyboards and mouse, stereo headsets Short distance, simple signals

Wireless connection Access point with cable connection to the network IEEE wireless LAN card

Figure 1: Mobile Devices

IEEE802.11x standards Developed by IEEE (Institute of Electronic and Electrical Engineers) Have many standards (e.g. IEEE802.11a, IEEE802.11b,IEEE802.11g, etc) Began in 1990 Took 7 years to complete the first standard

Products available in the Market Only products of three standards IEEE802.11b First product in the market IEEE802.11a and IEEE802.11g arrive almost simultaneously IEEE802.11n finalized in 2010

comparison IEEE b IEEE g IEEE a IEEE n (Draft) speed11 Mbps54 Mbps 300Mbps Frequency2.4 GHz 5 GHz 2.4 GHz Advantages Popular inexpensive Compatible with IEEE802.11b Avoid interference with other devices (such as cordless phones, microwave oven) Faster than version b and g Compatible with b and g

Bluetooth Low-cost, low-power Cover 10 meters Max speed: 700 Kbps. Use 2.4 GHz radio frequency Not a competitor of IEEE Replace cables in short distance

User Knowledge Lack of security features in mobile devices Immature wireless technology Security features not turned on Users unaware of security problems

Eavesdropping Figure 2 Eavesdropping by attacker

Program downloading Small memory More often to download program

Eavesdropping Difficult to discover Can use ordinary mobile device to attack (e.g. notebook computer) Software available in public domain Can attack from 20 miles away

Potential thread of download programs Reading or writing files (such as passwords) on the devices Delete files Connecting to other computers or devices perform illegal operations (such as hacking)

Jamming

Steps in jamming Listen to communication first Collect information Break the communication Impersonate the jammed user to continue communication Or impersonate the server

Jamming

Man-in-the-middle Listen to communication Intercepts the message Modify or add data in the message Confidential and integrity problem

Identity of attacker Mobile device is small (e.g. PDA) Difficult to detect Difficult to locate the attacker