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Wireless Communication Systems

Wireless Communication Systems. Background of Wireless Communication. Wireless Communication Technology. Wireless Networking and Mobile IP. Wireless Local Area Networks. Wireless Personal Area Networks. Wireless Metropolitan Area Networks. Wireless Wide Area Networks.

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Wireless Communication Systems

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  1. Wireless Communication Systems Background of Wireless Communication Wireless Communication Technology Wireless Networking and Mobile IP Wireless Local Area Networks Wireless Personal Area Networks Wireless Metropolitan Area Networks Wireless Wide Area Networks RFID - Radio Frequency IDentification

  2. Outline • Definition • How does it work? • Advantages and Disadvantages • Frequency & Standards • Application • Security • Future

  3. Outline • Technical details • Applications • Privacy and security • Challenges and controversy • Current research

  4. Definition • Short for radio frequency identification. • The term RFID is used to describe various technologies that use radio waves to automatically identify people or objects.

  5. What are RFID Systems? • Radio Frequency Identification Systems • Identification system that consists of chip-based tags and readers • Data is stored and retrieved remotely using radio waves • Onboard sensors • Product information

  6. Bar Codes vs RFID Think of barcodes and how much easier they’ve made our lives. For shoppers the checkout is faster while for companies it is easier to control stocks.

  7. How does it work? RFID tags are tiny microchips - about the size of a full stop on your computer screen. • That hold a unique identifier number. • They are attached to a small antenna. RFID System Components: • Chip: will include memory and some form of processing capability. • Reader:read the radio frequency and identify tags. • Antenna: provides the means for the integrated circuit to transmit its information to the reader.

  8. Two different kind of tags: • Passive Tags: are small and cheap (about 6 pence each), get all their power from the signal sent by the reader, but only work at a range of up to five meters and require you to install an array of expensive readers (£250 - £3,000 each). (1£=1.625$) • Active Tags: are larger, because they need a battery, and more expensive (about £6), but have a much wider range and can be read with fewer and cheaper readers. Disadvantage: • adds cost to the tag • run out of power eventually Note: RFID tags can be combined with sensors. which have been used to monitor the temperature of perishable goods. Other sensors that have been used with active RFID include humidity, shock/vibration, light, radiation, temperature.

  9. Frequency RFID tags and readers must be tuned into the same frequency to enable communications. 1. Low frequency : (125 to 134 KHz) 2. High frequency : (850 MHz to 950 MHz ). 3. Ultra High Frequency : (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) Air-interface: This is a specification for how tag and reader talk to each other.

  10. Advantage & Disadvantage • Advantage: • Reduce system cost • Automation • Speed up jobs,… • Disadvantage: Security problems High cost of RFID system Limited Operation Range

  11. Application RFID systems can be used just about anywhere, from clothing tags, to missiles, to pet tags, to food -anywhere that a unique identification system is needed. • Supply Chain Management (SCM) • Passport • Transportation • Automotive • Identification • Product tracking • Sports • Identification (Human & Animal) • Health

  12. RFID App : SCM • The United States Department of Defense has successfully used active tags to reduce costs and improve supply chain for more than 15 years. • inventory systems: • Eliminating the discrepancy between inventory record and physical inventory. • Prevent or reduce the sources of errors. Benefits of using RFID include the reduction of labor cost.

  13. RFID App: Passport • Passport: RFID tags are being used in passports issued by many countries. The first RFID passports ("e-passports") were issued by Malaysia in 1998. (thin metal lining).

  14. The Moscow Metro, was the first system in Europe to introduce RFID smartcards in 1998. • Taiwan the transportation system uses RFID operated cards . The Easy Card is charged at local convenience stores and metro stations, and can be used in Metro, buses, parking lots and taxis. • In Singapore, the public transport network of buses and trains employs passive RFID cards. Traffic into the crowded downtown areas of the country is regulated by variable tolls imposed using an active tagging system combined with the use of stored-value cards. RFID App: Transportation

  15. RFID App: Automotive • Microwave RFID tags are used in long range access control for vehicles. Since the 1990's RFID tags have been used in car keys to prevent theft. Without the correct RFID, the car will not start. • Starting with the 2004 model year, a Smart Key/Smart Start option became available to the Toyota Prius. Since then, Toyota has been introducing the feature on various models around the world under both the Toyota and Lexus brands, including the Toyota Avalon (2005 model year), Toyota Camry (2007 model year), and the Lexus GS (2006 model year). The driver can open the doors and start the car while the key remains in a purse or pocket.

  16. RFID App: Identification • Animal Identification: RFID chips for animals are extremely small devices injected via syringe under skin. Under a government initiative to control rabies, all Portuguese dogs must be RFID tagged by 2007. When scanned the tag can provide information relevant to the dog's history and its owner's information. • Human Identification:

  17. RFID App: Human Identification • Implantable RFID chips designed for animal tagging are now being used in humans. An early experiment with RFID implants was conducted by a British professor who implanted a chip in his arm in 1998. Night clubs in Barcelona, Spain and Rotterdam use RFID, to identify their VIP customers, acts as a debit account from which they can pay for drinks. • Prison • Mexican Attorney General’s office did it hurt? made of glass, the frequencies used are in the normal radio spectrum and experts currently don't predict any particular health issues.

  18. RFID App: Product Tracking & Sports Product tracking: • library book or bookstore tracking • airline baggage tracking Sport: • Football (Ticket) • Ski • RFID tags provide skiers hands-free access to ski lifts, Tracking skier.

  19. RFID App: Health • Track a patient's location. • Provide real-time tracking of the location of doctors and nurses in the hospital. • Track the whereabouts of expensive and critical equipment. • Control access to drugs.

  20. Future of RFID • Consumer goods are unlikely to be tagged on a large scale before 2012. • Civil liberties groups are concerned that much of the talk about the technology has focused on the benefits to business, rather than the implications for consumers. • "When you look at these tags, you see an interesting technology that has the potential to save money for companies".

  21. Security • In the US, retail giant Wal-Mart “razor blades”. • Security experts are warned against using RFID for authenticating people due to the risk of Identity Theft. For instance a Mafia Fraud Attack.

  22. Regulation and Standardization • EPCglobal • EPCglobal is working on international standards for the use of RFID. There is no global public body that governs the frequencies used for RFID.

  23. Components of an RFID system

  24. Layout of a transponder

  25. 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

  26. Data capacity • Normal range is from a few bytes to several kilobytes • 1-bit transponders • Useful for simple monitoring • Low cost

  27. 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

  28. 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

  29. 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

  30. Technical details

  31. Applications • Keyless entry • Electronic Product Code (EPC) • Proximity cards

  32. Applications (cont’d) • Payment tokens • Contact-less credit cards • Automatic toll-payment • Euro banknotes • Passports

  33. Applications (cont’d) • Libraries • Security device • Bookstores

  34. More applications • Animal and human implantation • Avid • Pet-ID • VeriChip • RFID-privacy legislation • REAL ID Act

  35. Privacy Concerns • Clandestine tracking • Inventorying

  36. 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

  37. Other challenges and concerns • Big Brother is watching • Worker displacement • Dependent on orientation • Blocked signals • Cost • No standard

  38. 4 requirements for consumer use • Notify the consumer • Visible and easily removable tags • Disabled at point of sale • Tag the product’s packaging

  39. Benetton Controversy

  40. Smart-shelf system

  41. Current Research • Trevor Pering (automatic configuration) • Eric Dishman (memory impairment) • PSA Corporation, Hutchinson-Whampoa, P&O (anti-terrorism)

  42. 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

  43. 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

  44. More open research issues • Rogue scanning and eavesdropping • Nominal read range • Rogue scanning range • Tag-to-reader eavesdropping • Reader-to-tag eavesdropping

  45. Open research issues (cont’d) • Authentication • Denial of service

  46. 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

  47. 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.

  48. References • http://news.bbc.co.uk • http://www.superrfid.net • http://www.rfidgazette.org • http://www.wikipedia.com • http://www.Rfidjournal.com • http://www.rfidinc.com • http://www.rfidc.com • http://www.edn.com • Thanks to Donia Malekian and Judy Chen for their contribution to this presentation. Some contents are based on “RFID A Key to Automating Everything” (RFIDEverywhere-SciAm.pdf) by Roy Want

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