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12 - Wireless Networks - Wireless Communications - Coggle Diagram
12 - Wireless Networks -
Wireless Communications
General wireless concepts
Radio waves have a frequency between 3 Hz and 300 GHz
Spectrum-use techniques (simultaneous use of the limited radio frequencies)
Spread spectrum
A message is broken in multiple pieces, and each piece is sent at the same time but using a different frequency.
Frequency Hopping Spread Spectrum (FHSS)
Early implementation of the spread spectrum concept
Transmit data in series across a range of frequencies, but only one frequency at a time is used
Direct Sequence Spread Spectrum (DSSS)
Employ frequencies simultaneously in parallel
Chipping code: Special encoding mechanism to reconstruct data even if parts of the signal were distorted because of interference
Orthogonal Frequency-Division Multiplexing (OFDM)
Use a digital multicarrier modulation scheme that allows for a more tightly compacted transmission
The modulated signals are perpendicular causing no interference with on another
Multiple Input, Multiple Output (MIMO)
Wireless communication technology that uses multiple antennas at both the transmitter and receiver ends to improve the performance of a communication link.
Used in modern wireless communication systems
Time Division Multiple Access (TDMA)
Digital communication technology used in various wireless communication systems (e.g. mobile, satellite)
Multiple access scheme that divides the available communication channel into time slots allowing multiple users to share the same frequency without interfering with each other
Code Division Multiple Access (CDMA)
Allow multiple users to share the same frequency band simultaneously.
One unique code to each entity
Bluetooth
2.4 GHz frequency
Operates between devices that have been paired
Technologies
Bluetooth Low Energy
For IoT, edge/fog devices, mobile equipment, medical devices, fitness trackers
iBeacon
Location-tracking technology developed by Apple on BLE
Zigbee
IoT equipment communication concept based on Bluetooth
Encrypted communication using 128-bit symmetric algorithm
Attacks
Bluesniffing
All devices are vulnerable
Bluesmacking
DoS attack against a bluetooth device
All devices are vulnerable
Bluejacking
Send unsolicited messages to bluetooth-capable devices without the permission of the owner
All devices are vulnerable
Bluetooth Forward and Future Secrecy (BLUFFS)
All devices are vulnerable
Bluesnarfing
Unauthorized access of data via a bluetooth connection
Bluebugging
Grant an attacker remote control over the hardware and software
Radio Frequency Identification (RFID)
Readable up to 100m away
Near-Field Communication (NFC)
Readable up to 4cm away
Wi-Fi attacks
War driving
Using a detection tool to look for wireless networking signals
Rogue Access Points
Defense = Operate a wireless intrusion detection system (WIDS)
Unauthorized access points
Evil twin
Must duplicate
MAC address
Wireless channel
High power rating
SSID
Disassociation
Send disassociation frame or de-authentication packet to disconnect a user.
Jamming
Transmission of radio signals to intentionally prevent or interfere with communications by decreasing the effective sign-to-noise ratio
Replay attacks