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    Radio Frequency Identification Technology: Development ... Radio Frequency Identification Technology: Development ... Document Transcript

    • Radio Frequency Identification Technology: Development, Application, and Security Issues. O. Shoewu, M.Sc.* and O. Badejo, B.Sc. Department of Electronics & Computer Engineering Faculty of Engineering, Technology and Environmental Sciences, Lagos State University * E-mail: engrshoewu@yahoo.com ABSTRACT by an optical scanner. RFID, on the other hand, has the ability to identify and track products and RFID (Radio Frequency Identification equipment in real-time without contact or line-of- Technology) is a field of computerizing sight and the tags can withstand harsh, rugged recognition process that is progressively gaining environments. thrust in recent years and is now being seen as a means of enhancing data handling RFID is a flexible technology that is convenient, procedures, complimentary in many ways to easy to use, and is well suited for automatic other data capture technologies such as bar operations. It combines advantages not coding. available with other identification technologies such as bar codes. RFID can be supplied as A variety of devices and associated systems read-only or read/write, does not require contact have been developed to satisfy a broad series of or line-of-sight to operate, can function under a applications. Regardless of the diversity of variety of environmental conditions, and applications, the ideologies upon which they are provides a high level of data integrity. In based are quite understated, even though the addition, because the technology is difficult to technology and technicalities associated with counterfeit, RFID provides a high level of their function can be quite innovative. Just as security. one need not know the workings of a mobile phone or personal computer to use these items; RFID is used as a direct replacement for it is not obligatory to know the technicalities to barcode technology. The advantages it offers identify with the principles, considerations, and include 100% read accuracy, the ability to potential for using RFID in a practical sense. survive demanding environments, and the This piece however focuses on the security elimination of line-of-sight requirements. The aspects of the technology and various possible term RFID simply describes the use of radio applications apart from regular inventory frequency signals to provide automatic management. identification of items. (Keywords: RFID, electronic security, wireless, data communication, tags, transponders) RFID TECHNOLOGY An RFID system is composed of tags, which INTRODUCTION carry the data in suitable transponders, and an RFID reader, which retrieves the data from the Radio Frequency Identification (RFID) tags. Products that contain RFID tags embedded technologies provide a wireless means of in them or fastened to them enable stored communication between objects and readers. information to be transferred from an RFID tag to RFID involves the use of tags, or transponders, a remote reader through radio frequency waves that collect data and manage it in a portable, of a specific wavelength. There currently is not a changeable database. A similar technique definite industry standard for wavelength, but the known as bar code represents a sequence of most common applications around the world use lines (usually vertical) and number used to store wavelengths of 125 KHz and 13.56 MHz. object information such as identity, date of manufacture, price etc., which can be revealed The Pacific Journal of Science and Technology –144– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • Initially, data is written to the RFID tag enabling Antenna it to identify and characterize a product as a particular manufactured good with a determined The function of the antenna (which is attached to application. At some later point, an RFID remote a reader) is to transmit an electromagnetic field reader will scan and acknowledge the that activates a passive tag when it is within a information once the tag is within range of an given reading range. Once a passive tag is electromagnetic field activating the tag to activated, it can transmit information from its perform a user defined function. antenna to that of the reader where it is processed. During rewriting applications, the Some of the components may be combined into antenna of the reader acts as a relay device in one hand-held unit to allow user mobility. Also, the reverse direction, the reader communicates many passive RFID transponders have a message through its antenna, which transfers antennas sealed with the tags to give them and stores the new data to the activated greater read-write abilities. transducer via its antenna (Figure 1). The RFID tag’s antenna is practically maintenance free and can be configured in a variety of shapes and RFID Tags sizes ranging in size from a grain of rice to the size of a brick [Zebra Technologies, 2002]. There are two classifications of RFID tags: passive and active. The means by which they receive power for transmission determines their Readers classification. Passive tags depend on a power source provided by the RFID reader’s energy Readers may be integrated into handheld field and may have read-write or read-only computers or they may be stationary and capabilities, whereas, active tags have an positioned at strategic points, such as a facility internal power source and are rewritable. entrance or on an assembly line [Zebra Passive tags generally have shorter read ranges Technologies, 2002]. The handheld readers but have a life that usually outlasts the object offer portability, however, the stationary devices that it is identifying. offer a larger reading range. Active tags have longer reading ranges, high As stated above, readers have an antenna for memory, and better noise protection. However, sending and receiving signals and a processor these tags are larger and heavier, more for decoding them. The reader receives expensive, and have a shorter life (3 – 10 years) instructions and information from the antenna than passive tags. Read-only tags are used for through the scanner, which is a part of the simple identification purposes because they can reader that examines analog output from the only store a limited amount of information that antenna. The scanner’s information is then cannot be altered. Such tags may be used to converted into a digital format by the reader, identify a package of nails or screws because which the computer or processor can then use they have many applications and are not for data analysis, recording, and reporting. There designated to a particular item or activity. are readers today that can simultaneously read 100 to 2000 tags per second. For these tags to retain their characteristic composition and give accurate and reliable identification of object, certain specifications Read Ranges and Tag Frequency need to be ensured. These include design weight of 50 grams, a lifecycle of being written to Reading range may be determined by the power 100,000 times, data retention greater than 10 available or the frequency of the tag. Generally, years without power, and the durability to active tags that have power supplies embedded withstand being dropped to concrete from a in them have a larger reading range than those height of 1 meter a multiple number of times of passive tags; however, they do come at a [Identec Solutions, 2002]. cost. The Pacific Journal of Science and Technology –145– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • Figure 1: RFID Reader and Tag Communication Flow Diagram Some companies on today’s market claim that tags, but they tend to be line of sight dependent, their active tags can be written to and read up to orientation sensitive, and require more power 100 meters in free air. Passive tags on the other [Liard, 2003]. hand have a read range of up to 2 meters. Other factors affecting reading distances include the frequency at which the tags communicate. Table APPLICATIONS OF RFID TECHNOLOGY 1 shows the classification of four frequency bands used in RFID tags, their frequencies, and While the potential for RFID applications their reading ranges. appears virtually limitless, there are only a few applications that have been implemented using the technology which are continually being used. Table 1: Frequency Classifications In the year 2000 the most common uses for radio frequency identification technologies Frequency Frequency Band Reading included: transportation, materials management, Classification (Hz) Range and security and access control. Currently, there Low Frequency 125 kHz 0.3 meters are a variety of other applications for RFID in agriculture, construction, and athletics. High Frequency 13.56 MHz 1 meter Ultra High Frequency 433 MHZ - 2.45 GHz 1-3 meters Security (UHF) Microwave 2.45 GHz - 300 GHz 2+ meters Frequency Many businesses use RFID to control access to hotels and business facilities by attaching a tag to an employee’s room card or ID badge. Such technology ensures that only authorized persons are allowed access to particular rooms or The most commonly used tags are classified as entrances. This application is also becoming low frequency because they are more easily more common in nursing homes and hospitals readable through materials and are not as where the management and tracking of orientation sensitive as higher frequency tags. individuals is very important, and alarms are Generally speaking, higher frequencies have more discrete. greater reading ranges and are less sensitive to noise than the lower frequency tags. Other security features include RFID chips embedded into automobile keys that enable the Conversely, RFID tags with microwave car only to start if the key has the proper chip frequency do have greater read ranges and embedded into it. Video stores and libraries are higher reading speeds than lower frequency also applying radio frequency devices to The Pacific Journal of Science and Technology –146– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • checkout rentals to detect stolen or misplaced are dedicated to speeding-up traffic flow and items. Law enforcement officers are now able to decreasing delay time while making travel smart track credit cards, jewellery, vehicles, and and efficient. artwork by radio frequency tags embedded in these objects. Construction Athletics Currently there is little use of RFID in construction, but there have been three uses Golf ball identification and tracking devices have identified by the Construction Industry Institute been implemented for accurate identification based in Ghana: compressed gas cylinder purposes; however, there may be a better tracking, small tools management, and market for the tracking of baseballs in today’s equipment monitoring [CII, 2001]. homerun hitting bonanza. Other potential applications in construction Another use for RFID tags in athletics is include ideas or case studies on the implemented in almost all major track and field development of material delivery and events. “Road races”, running races, or management tracking systems, guided controls marathons in the streets, use shoelace RFID of equipment, tags that communicate fatigue or tags to get race results of runners as they cross excessive stress in concrete and steel members, the start and finish lines where there time is safety, and several other area. officially kept regardless of when the runner begins the race. These technologies are also being used to track athletes to verify that the Global Positioning System (GPS) path travelled is the same as the course defined by the race officials. Global Positioning Systems (GPS) have revolutionized the means to accurately locate and identify objects on the earth’s surface using Transportation a system of satellites in space and transmitters and receivers on earth. The combination of GPS The transportation industry is one of the leading and RFID identification tags has made “real- users of RFID technology and they have time” tracking a reality. Materials and assets can identified and implemented numerous be identified and tracked as they are installed or applications. RFID applications in transportation transported. include railroad car management, traffic management, tolls and fees, fare collection, equipment identification, fleet management, Manufacturing solid waste hauling, and fuel dispensing [CII, 2001]. When a hometown commuter passes Radio frequency identification systems allow the through an express toll lane, an RFID tag alerts tracking of work-in-progress in automobile the tag reader that someone has passed manufacturing and in computer hardware through the toll and the reader then identifies the manufacturing. Such technology allows commuter and communicates the charge to an managers to track goods through the account setup in a networked computer system. manufacturing process and then the tags can either be reused on other products coming down Tractor-trailer traffic is also managed in much the assembly line or they may stay permanently the same way through weigh stations. Once a fixed to the product to provide a secure serial semi tagged with RFID technologies enters an number. interstate highway it stops at the first weigh station along its journey on the interstate to be identified and approved, then throughout the rest EMERGING APPLICATIONS of its passage along that same stretch of highway it is not required to stop at any other Transportation and Access/Security weigh stations. The truck is simply tracked by RFID technology along the highway. The At the American Association of Airport transportation industry and related businesses Executives (AAAE) Conference in May 2002, The Pacific Journal of Science and Technology –147– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • TransCore and Gatekeeper Systems, Inc. Airports – Security and Baggage Handling partnered up to create a Ground Transportation Management System (GTMS) that would deal RFID tags could be used to track and identify with travel and security round airports. The airline luggage and passengers increasing technology allows authorized vehicles (airport national security, speeding up luggage sorting busses, taxis, cargo vans, etc.) to enter the and transfer, and decreasing expenditures grounds. This enables airports to have un- resulting from heightened security measures. manned security checkpoints that monitor, track, The International Air Transport Association control, record, and report vehicle operations. (IATA) believes this technology has countless Nearby traffic congestion and air pollution from potential benefits for simplifying passenger travel vehicle emissions would be reduced, and airport for airports and airlines [Conway, 2001]. revenues from commercial vehicle access charges would increase because vehicles would The major advantages of RF technology in be charged on a “per use” basis [Parker, 2002]. baggage handling are an increased journey speed of luggage as a result of faster read rates This technology is also being used at Fort and elimination of human intervention in McPherson Army base in Georgia. Passive misdirected bags and security procedures sticker tags are being used at read ranges of [Conway, 2001]. Airline travel consists of 100 approximately 20 feet, powered by the radio million customers each year making the cost of frequency that interrogates it, to identify, allow the tags and the read range of baggage a great access, and record vehicles entering the Army concern. base. When a vehicle’s tag is intercepted, photo identification and other information is sent to the In November 2001 Jacksonville International computer at the guard post allowing security to Airport became the first airport to begin verify that proper authorities and passengers are constructing and implementing the world’s first entering [Jackson, 2002]. all-radio frequency baggage tracking and identification system [IIE Solutions, 2002]. The RFID tagging system will make curb-side check- Supply-Chain Management in and security inspections more efficient by allowing readers to identify not only where the Retailers are very interested in turning the baggage is going, but also passenger supply chain management industry into an information, and a detailed travel history of the RFID-dependent business as long as it is cost bag. However, until the entire airline industry efficient. They plan to tag every pallet and carton follows suit there is going to be a double coming out of distribution centers to reduce standard for those implementing new losses from out-of-stock, stolen, or lost products, technologies. and the industry believes that with increased tracking ability it will increase revenues by leveraging inventory information into smarter Government Regulations – Tires marketing to retailers [Schwartz, 2003]. In the wake of massive Firestone tire recalls, the US Congress passed the TREAD Medical Applications (Transportation, Recall, Enhancement, Accountability, and Documentation) Act Medical applications include allowing restricted mandating that car makers closely track tires access and tracking patients and guest with from the 2004 model year on, so they can be authorized wristbands through hospitals. “Hugs recalled if there’s a problem. RFID tags with Kisses,” produced by Xmark, is an embedded into tires will identify the electronic tagging and monitoring system for manufacturer’s name and plant, store the time controlling the movement of newborn babies in a and date of manufacture, tire dimension, and hospital environment. The system comprises pressure specifications. active trans-ponders attached to the baby, monitoring receivers at doorways, and a Once the tire is installed on a new vehicle the computer networking system to reduce the risk tire identification number and the vehicles’ of abduction and to ensure mother and child Vehicle Identification Number (VIN) will be identification The Pacific Journal of Science and Technology –148– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • downloaded to a computer database enabling troops and to track other important information manufacturers to make targeted, quick recalls. such as medical history. RFID testing is currently being conducted using FUTURE APPLICATIONS RF tags on grocery items. Just as in the airline industry, there is going to be a double standard RFID technology has the capability to be applied until there is complete adoption of RFID in in all industries, but as stated above, there is a supermarkets. IBM has contemplated the idea of high demand on standardization, economy, and an all RFID grocery store where the customer versatility of radio frequency identification tags. picks up the items that he/she is interested in Future ideas are derived from many of the new purchasing and simply walks out the door. In and current uses of RFID. However, there are this case the grocery items have RFID tags several ideas that even government configured so that when the customer leaves the organizations may draw interest in. The supply- store an RFID reader mounted at the doorway chain and sales businesses have adopted the scans the items and directly charges customers’ idea of introducing radio frequency technology to accounts in the store’s database. Furthermore, help persons such as pharmaceutical sales cell phones equipped with RFID may have the representatives track inventory by simply potential to make all of these transactions even walking into the drug storage room. The sales simpler. representative could determine which products are moving and assist drug companies in better The development of this technology is still a long marketing their products [Schwartz, 2003]. way behind in developing countries like Nigeria. This is partly due to the level of awareness of Government agencies could identify and track the economic importance and potentials of inmates in jails and prisons in real-time to keep setting up RFID. Nevertheless, a number of tight security surveillance on convicted criminals. professional organizations in Information and Public schools could use RFID to determine Communication Technology (ICT) in the country student attendance and track suspicious kids for are now discussing the topic and it is expected the safety of the public. These applications do that in the not-too-distant future, ICT impede on individual’s personal rights and stakeholders will begin to consider as a freedom, but some day there may be a benefit to profitable venture to invest in. society that exceeds the cost of being tracked within certain public bounds. RFID LIMITATIONS Amusement parks are developing wristbands that function much like the wristbands in Standardization hospitals and nursing homes, but they would have the potential to be used to charge Currently standardization among RFID concessions and souvenir purchases to a user’s manufacturers’ readers, tag frequencies, and account just as a credit card. recording software is causing lower consumer confidence in the RFID market. The automobile industry may have a jump start in tracking vehicle’s maintenance and service Technologists are hiding their information and records by means of smart tags located within avoiding standardization because it may give the vehicle’s tires. Such information in another manufacturer a competitive advantage conjunction with the car’s odometer could track that movers expect to gain in fully developing the the mileage of the vehicle and alert the driver RFID market [Roberts, 2002]. On the other when the tires need to be rotated and the engine hand, there is a list of potential standards that oil needs to be changed. Since the tags are industry associations, user groups, and vendors rewritable, standards would enable the car to see that could open the floodgates to extensive have an up-to-date service and maintenance RFID deployment. record regardless of the mechanic or station that has provided work. According to AMR Research, eventual standards will affect the following issues [Kay, 2003]: The US military has discussed the idea of producing smart dog tags to easily identify • Global RFID frequencies The Pacific Journal of Science and Technology –149– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • • Interoperability it has in developing RFID technology with the • Use of active or passive tags potential to cut cost and in return, increase • Data formats (syntax, data structures, and sales. Companies such as Wal-Mart, Coca-Cola, encoding) and Proctor and Gamble, all multi-billion dollar • Methods of identification and presentation sales companies, are looking to improve supply- • Communications between tags and objects chain efficiency with RFID tags that may cost as and tags and readers little as five-cents each. When these companies find a way to use RFID technologies Standardized RFID tags would enable successfully, the rest of the retail and consumer contractors to track and manage a variety of sales world will surely undergo a technological manufacturers’ tags, which are fixed to different revolution. construction equipment and materials, with a single RFID reader. Until standards are set, the cost of implementing RFID technologies will Interference arguably outweigh the benefits. There are two identifiable causes of interference in reading RFID tags. Metal materials have Cost caused big concerns from the start of RFID testing and as the applications and use of radio The supply-chain revolution and widespread frequency technology grows so does the RFID implementation is expected to take place concern with frequency interference. when the risk of investment is lower. Some believe this will be when the price of an RFID tag Other materials such as rubber and water may reaches five-cents (US). Currently tags cost also cause shortened read ranges, but these are around fifty-cents (US), but that is about a challenges that can be overcome with further quarter of the cost from four years ago. As RFID research and testing. technology continues to develop and the demand for smart chips increases by the millions, the cost of each tag will continue to Tracking People’s Freedom drop. In an attempt to make tracking and management Currently, RFID technology cannot economically more efficient, the RFID industry is striving not to compete with bar codes, but there soon will be a infringe upon the freedom of its users. A day when the benefits of RFID tags outweigh common use of RFID tags may be to tag their costs. When investing in new technologies clothing items or foods products, but the tag is one must prepare a detailed business plan to only functioning properly (not infringing on the make sure that they will have a profitable return privacy and security of its owner) if it has a “kill on investment. However, there are many switch” that is guaranteed to shut the tag off concerns that one must evaluate beyond the when a purchased item clears the store. In the issue of cost: tag size and packaging, tag manufacturing sector, workers embedded with generation and application, quality, deployment RFID should not be tracked once they leave the environment, required physical infrastructure, jobsite, preserving their civil liberties. However, required information systems infrastructure, and there may be limitations for warranty items and technology and communications standards [Hill, tags that are used to track such things as 2003]. vehicles and the transportation of goods. Buyers trying to minimize costs in determining which tags are most applicable and efficient to OBSERVATIONS AND CONCLUSION their situation must keep two things in mind: the quantity of tags necessary and the Despite the growing RFID market, the following capacity/limitations of each tag. Technologists are some of the major contributing factors believe that the Wal-Mart company (US based) preventing the adoption of new RFID may influence the RFID industry in such a way technologies across the full range of industries. that the rest of the world would follow suite. Wal- Mart’s investment in the Auto-ID (RFID research • Lack of standardization and development) Center expresses the interest • High costs of implementation The Pacific Journal of Science and Technology –150– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • • Slow technology development and 7. CII. 2001. “Radio Frequency Identification deployment risks Tagging. RFID Tagging Research Team – Research Summary”. CII Research Team. March • Elimination of unskilled labor 2001. 151. Pilot studies have proven that RFID is an 8. Zebra Technologies. 2002. “RFID: The Next effective method of reducing project activity Generation of AIDC (Automatic Identification times and saving project costs. However, project Data Collection)”. Zebra Technologies: Vernon owners and managers have not yet fully Hills, IL. comprehended the benefits of using RFID. As RFID technologies develop, the cost of RFID 9. RFID Journal Staff Writer. 2003. “The Wal-Mart equipment and software will continue to become Factor”. RFID Journal. March 2003. http:// www.rfidjournal.com/article/articleview/346/1/1/ more affordable to all industry users. In just the last four years, the price of RFID tags has 10. CII. 2003. “RFID Applications for Owners and decreased by 75%. Additionally, RFID systems Contractors”. CCI Research Team 151. ADCIC. require no maintenance and can be used repeatedly. 11. Schwartz, E. 2003. “Wireless World: RFID is About to Explode – Ten-cent Pieces of Wireless Future case studies and project RFID sampling Equipment are Being Deployed by the Billions”. are needed to increase contractor and owner InfoWorld Media Group, Inc. awareness of the potential savings of human http://www.infoworld.com/archives/emailPrint.jsp? R=printThis&A=/article/03/01/31/05wireless_1.ht resources, project-scheduling times, and project ml costs. The industry as a whole must determine today where RFID is applicable so that together 12. Roberts, S. 2002. “As RFID Vendors Prepare for they can overcome current limitations and Takeoff, Analysts Strike a Note of Caution”. produce transponders with greater read ranges, Frontline Solutions. February 2002. systems with cheaper implementation costs, and tags with increased durability for the future. 13. Thomas, D. 2002. “Now is the Time to Adopt RFID Tags (Radio frequency identification tagging)”. Reed Business Information Limited: Surry, UK. REFERENCES 14. Identec Solutions.2006. “Introduction to RFID”. 1. RFID Journal Staff Writer. 2002. “First RFID/Bar Identec Solutions: Addison, TX. Code Scanner”. RFID Journal. September 2002. http://www.identecsolutions.com/products.asp http://www.rfidjournal.com/article/articleview/78/1/ 1/%20September 15. Allen, R. 2002. “Making Industry Bigger, More Profitable, and Efficient: New Developments will 2. Liard, M.J. 2002. “Retail Automation Equipment: Add “Smarts” to Business”. Electronic Design. 21 A Vertical Market Analysis of Usage and Plans October 2002. 173-175. for Wireless, Emerging, and Traditional Technologies”. Venture Development 16. Hill, J. 2003. “Evaluating RFID? Don’t Wait for the Corporation: Natick, MA. Five-Cent Solution”. February 2003. http://www.frontlinetoday.com 3. Electronic Engineering Times Staff Writer. 2001. “Three Firms Propose a Standard for RFID”. Electronic Engineering Times. ABOUT THE AUTHORS 4. Albright, B. 2002. “Will RFID be the Answer People Want it to be?” November 2002. O. Shoewu, M.Sc., B.Sc.(Hons), MNSE, serves http://www.frontlinetoday.com as a Lecturer at the Lagos State University. He earned his M.Sc. and B.Sc. from the Lagos 5. Sabetti, A. 1994. “Applications of Radio State University and the University of Lagos in Frequency Identification (RFID)”. Texas 1992 and 1995, respectively. He is presently a Instruments Registration and Identification postgraduate student working towards a Systems, SCAN-TECH 1994. Doctoral degree in Electronics. His research interests are in the areas of electronics, 6. IIE. 2002. “Florida Airport Gets First RFID computers, and communications technology. System”. IIE Solutions. 34(7):14-14. The Pacific Journal of Science and Technology –151– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
    • O.A. Badejo, B.Sc. is presently employed by an Information Technology company in Nigeria. He studied Electronic and Computer Engineering at the Lagos State University, Epe Campus, and holds a Bachelor of Science Degree. SUGGESTED CITATION Shoewu, O. and O. Badejo. 2006. “Radio Frequency Identification Technology: Development, Application, and Security Issues”. Pacific Journal of Science and Technology. 7(2):144-152. Pacific Journal of Science and Technology The Pacific Journal of Science and Technology –152– http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)