Radio Frequency

Identification

(RFID)Judy Chen

Outline

• Overview• Taxonomy• Technical details• Applications• Privacy and security• Challenges and controversy• Current research

What is RFID?

• Radio Frequency Identification• Identification system that consists of

chip-based tags and readers• Data is stored and retrieved remotely

using radio waves– Onboard sensors– Product information

Components of an RFID

system

Layout of a transponder

Taxonomy

**insert figure 2.1 (pg. 12)

Operation type

• Full and half duplex systems– Transponder’s response is broadcast when

the reader’s RF field is switched on

• Sequential procedure– Reader’s RF field is periodically switched off– Loss of power during breaks– Need auxiliary capacitors or batteries

Data capacity

• Normal range is from a few bytes to several kilobytes

• 1-bit transponders– Useful for simple monitoring– Low cost

Read only vs writeable

• Electrically erasable programmable read-only memory (EEPROM)– High power consumption– Limited number of write cycle

• Ferromagnetic random access memory (FRAM)– Lower power consumption

• Static random access memory (SRAM)– Rapid write cycles– Needs power supply for data retention

Power supply

• Passive– Require no internal power source or

maintenance– Tag reader is responsible for power

• Active– Require a power source– More reliable and efficient in rugged

environments

Frequencies of operation

• Low frequency – 30-300 kHz– Tags need to be closer to the reader– Poor discrimination

• High frequency/radio frequency– 3-30 MHz– Tags can be read from relatively greater distances– Tags can hold more information

• Ultra high frequency/microwave– >300 MHz– Longest range– More interference

Technical details

Applications

• Keyless entry• Electronic Product Code (EPC)• Proximity cards

Applications (cont’d)

• Payment tokens– Contact-less credit cards– Automatic toll-payment

• Euro banknotes• Passports

Applications (cont’d)

• Libraries• Security device

– Bookstores

More applications

• Animal and human implantation– Avid– Pet-ID– VeriChip

• RFID-privacy legislation– REAL ID Act

Privacy Concerns

• Clandestine tracking• Inventorying

Protecting Privacy

• Kill function• Normal tags

– Prevents unauthorized readings– Blocks electric waves– Jamming and interference

• Smart tags– Rewritable memory– Anonymous-ID scheme– Lightweight circuits

» Hash-function circuit

Other challenges and

concerns• Big Brother is watching• Worker displacement• Dependent on orientation• Blocked signals• Cost• No standard

4 requirements for

consumer use• Notify the consumer• Visible and easily removable tags• Disabled at point of sale• Tag the product’s packaging

Benetton Controversy

Smart-shelf system

Current Research

• Trevor Pering (automatic configuration)• Eric Dishman (memory impairment)• PSA Corporation, Hutchinson-Whampoa,

P&O (anti-terrorism)

SmartMoveX

• Low cost active badge system• A small radio transmitter is attached to

the person being tracked• Receivers are placed around the

building– Measure the RF signal strength from badge

transmissions to compute locations– Average error within 3.05 meters

Proactive Computing

• David Tennenhouse• Systems anticipate what we need • We do little to nothing• Networks of RFID readers will be

everywhere– Permanent and connected by cables – Ad hoc wireless network

More open research

issues• Rogue scanning and eavesdropping

– Nominal read range– Rogue scanning range– Tag-to-reader eavesdropping– Reader-to-tag eavesdropping

Open research issues

(cont’d)• Authentication• Denial of service

Conclusion

• RFID has many potential uses• Likely to play a key technological role• Perceptions of privacy and security vary• Privacy and security concerns must be

addressed

References

• Ohkubo, M., Suzuki, K., and Kinoshita, S. RFID privacy issues and technical challenges. Communications of the ACM, ACM Press (2005), 66-71.

• Want, R. RFID: A key to automating everything. Scientific American, 2003, 56-65.

• Juels, A. RFID security and privacy: A research survey. To appear in Proc. Of IEEE JSAC’06.

• Want, R. An introduction to RFID Technology. IEEE Pervasive Computing, 2006, 25-33.

• Wikipedia. http://en.wikipedia.org/wiki/RFID .• Finkenzeller, K. RFID Handbook. West Sussex, England:

Wiley, 2003.• CNET News.

http://news.com.com/2100-1017_3-1023934.html .• Krumm, J., Williams, L., and Smith, G. SmartMoveX on

a graph: An inexpensive active badge tracker. UbiComp, Springer-Verlag (2002), 299-307.