2 cissp ® Official Study Guide Eighth Edition

507
Class
Maximum permitted power
Typical range
3
1 mW
1 m
4
.5 mW
.5 m
Bluetooth devices sometimes employ encryption, but it is not dynamic and can usually 
be cracked with modest effort. Use Bluetooth for those activities that are not sensitive or 
confidential. Whenever possible, change the default PINs on your devices. Do not leave 
your devices in discovery mode, and always turn off Bluetooth when it’s not in active use.
RFID
Radio Frequency Identification (RFID)
is a tracking technology based on the ability to 
power a radio transmitter using current generated in an antenna when placed in a magnetic 
field. RFID can be triggered/powered and read from a considerable distance away (often 
hundreds of meters). RFID can be attached to devices or integrated into their structure, 
such as notebook computers, tablets, routers, switches, USB flash drives, portable hard 
drives, and so on. This can allow for quick inventory tracking without having to be in 
direct physical proximity of the device. Simply walking into a room with an RFID reader 
can collect the information transmitted by the activated chips in the area.
There is some concern that RFID can be a privacy-violating technology. If you are in 
possession of a device with an RFID chip, then anyone with an RFID reader can take note 
of the signal from your chip. When an RFID chip is awakened or responds to being near a 
reader, the chip (also called the RFID tag) transmits a unique code or serial number. That 
unique number is meaningless without the corresponding database that associates the num-
ber with the specific object (or person). However, if you are noted or recorded as the only 
one around while a reader detects your RFID chip code, then they can associate you and/or 
your device with that code for all future detections of the same code.
NFC
Near-field communication (NFC)
is a standard that establishes radio communications 
between devices in close proximity (like a few inches versus feet for passive RFID). It lets 
you perform a type of automatic synchronization and association between devices by 
touching them together or bringing them within inches of each other. NFC is a derivative 
technology from RFID and is itself a form of field-powered or triggered device.
NFC is commonly found on smartphones and many mobile device accessories. It’s often 
used to perform device-to-device data exchanges, set up direct communications, or access 
more complex services such as WPA2 encrypted wireless networks by linking with the 
wireless access point via NFC. Because NFC is a radio-based technology, it isn’t without its 
vulnerabilities. NFC attacks can include man-in-the-middle, eavesdropping, data manipula-
tion, and replay attacks.

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