– Speed of attacks
– Sophistication of attacks
– Attackers now detect weaknesses faster
– Distributed attacks
– User confusion
What is information security
Information security is achieved through a combination
of three entities
– Innermost layer consists of the products that provide the
necessary security
– Middle layer is people
– Outmost layer consists of procedures
Information security protects devices that store,
manipulate, and transmit the information
Wireless Advantages & disadvantages
Disadvantages
Radio frequency interference
– Signals from other devices can disrupt wireless
Health risks
– High levels of RF can produce biological damage
through heating effects
– It is not known if or to what extent lower levels of RF
might cause adverse health effects
Security
– Greatest disadvantage to wireless LANs
– Attacks on wireless networks: denial-of-service,
stealing passwords, altering messages
Advantages
Mobility
– Primary advantage of wireless technology
– Enables individuals to use a laptop computer that is
always in contact with the network
Easier and less expensive installation
– Installing network cabling can be expensive
– Significant time required to install network cabling
– Wireless technologies allow creation of an office in a
space where the traditional infrastructure doesn’t exist
Increased reliability
– Wireless LAN technology eliminates cable failures and
increases the overall reliability of the network
Disaster recovery
– Hot site has all the equipment needed for an
organization to continue running
Generally run by a commercial disaster recovery service
– Cold site provides office space but the customer must
provide and install all the equipment
– Many businesses use cold sites and WLANs as a major
piece of their disaster recovery plan
Wireless in our world
health care
The health care industry has embraced wireless
technology to improve patient care
Wireless LAN point-of-care computer systems
– Allow medical staff to access and update patient
records immediately
– Verify that medication is being administered to the
correct patient in the correct dosage
education
WLANs are ideal for colleges and schools
• Educational institutions were early users of WLANs
• Wireless LAN connections offer teachers and
students an important degree of freedom
– Teachers create classroom presentations on laptops
– Can access the school network wirelessly from
almost any location
• Most schools publish maps showing the location of
wireless access points
CWSP Guide to Wireless Security 17
travel
Travel industry is a leader in adopting wireless
technologies
– Most airports provide wireless access hotspots
– Some airports use wireless technology to keep track
of passenger luggage
• Wireless PDAs now replace walkie-talkies
• WLAN technology is used to communicate with the
aircraft
– Once it has parked or is taxiing on the ground
• WLAN technologies are not restricted to airplanes
bussiness
“Flatter” organizations
Business
– Employees are involved in team meetings that occur
away from their desks
• Wireless technology
– Has dramatically changed how and where business
meetings take place
• Has made the meetings more focused and productive
• Wireless LANs benefits
– Increased productivity, time/financial savings
Voice over wireless LAN (VoWLAN)
– Emerging wireless technology
– Uses the existing data WLAN to make and receive
telephone calls
– VoWLAN devices can forward business calls to their
mobile phones during regular business hours
What attacker can do?
- Steal personal data
- View wireless transmissions
- With freely available wireless packet sniffer
- Inject malware
- Download harmful content
- Cause loss of equipment
- Cause violation of an ISP agreement
- Identify “weak link” users
WLAN (Wireless LAN) Architecture
WLAN may include several access points
Dependent upon number of stations
– Maximum number varies: 10-100
Infrastructure WLAN
Stations communicate with access point
• Not directly with each other
Access point requires sufficient power, strategic
placement
Wireless access point (WAP)
Accepts wireless signals from multiple nodes
• Retransmits signals to network
– Base stations, wireless routers, wireless gateways
Ad hoc WLAN
Wireless nodes transmit directly to each other
– Use wireless NICs
• No intervening connectivity device
– Poor performance
• Many spread out users, obstacles block signals
Signal degradation
Noise
Significant problem
• No wireless conduit, shielding
Attenuation
Signal weakens
• Moving away from transmission antenna
Correcting signal attenuation
• Amplify (analog), repeat (digital)
Noise
Fading
Variation in signal strength
• Electromagnetic energy scattered, reflected, diffracted
signal propagation
obstacle effect signal travel, signal may
Pass through them
– Be absorbed into them
– Be subject to three phenomena
• Reflection: bounce back to source
• Diffraction: splits into secondary waves
• Scattering: diffusion in multiple different directions
LOS (line-of-sight)
Signal travels in straight line
• Directly from transmitter to receiver
wireless spectrum
Spans 9 KHz and 300 GHz
- Data, voice communication
- Arranged by frequencies which is from lowest to highest frequency
