RFID Standards An RFID system can utilize a few standards. The problem has been that there is no one universally accepted standard. Competing standards have been one of the more difficult issues for RFID, and as a result, most RFID applications have been closed systems. Standards and specifications may be set at the international, national, industry or trade association level, and individual organizations may term their own specifications as standard. Many industry standards and specifications set by individual organizations are based on international standards to make implementation and support easier and to provide a wider choice of available products. Standards can be applied to include the format and content of the codes placed on the tags, the protocols and frequencies that will be used by the tags and readers to transmit the data, the security and tamper-resistance of tags on packaging and freight containers, and applications use. The two largest drivers for RFID today are Wal-Mart and the Department of Defense (DOD). Both have issued mandates for their top suppliers to use RFID technology when shipping products to their distribution centers. They are both looking to accomplish the same thing, but have a slightly different long-term outlook. The ISO (International Standards Organization) and the EPC Global have both been leading figures in this debate. The ISO has their 18000 standard and the EPC Global Center has introduced the EPC standard. Wal-Mart has decided to use the EPC standard, where the DOD wants to use the EPC for general purposes, but use the ISO standard for air interface. This is putting a lot of pressure on the ISO and EPC to come to some kind of an agreement. EPC standard for air interface is not compatible with the ISO 18000 UHF (Part 6) standard. Both, the EPC and ISO 18000 (Part6) standards, deal with the tracking of merchandise through the supply chain. This is Wal-Mart s and the Department of Defense s primary focus at this time. The ISO 18000 (Part 6) standard only deals with air interface protocols, whereas the EPC standard also includes data structure. The desire is for these two protocols not to be mutually exclusive. There are several evolutions to the EPC standard. Class 1-Generation 1 is the current version of EPC. It is not backward compatible with Class 0. Generation 2 was hoped to be backward compatible with Class 0 but merging with the ISO 18000 standard will be difficult, if not impossible. Wal-Mart has said it will support both Class 0 and 1 but wants to settle on Class 1 Generation 2 when it is finalized. The EPC standard was developed for carton and pallet tracking within the supply chain. The finalization of EPC Class1 Gen2 is expected October 2004.
EPC Standards: What is EPC? The Auto-ID Center has proposed a new Electronic Product Code as the next standard for identifying products. The goal is not to replace existing bar code standards, but rather to create a migration path for companies to move from established standards for bar codes to the new EPC. To encourage this evolution, we have adopted the basic structures of the Global Trade Item Number (GTIN), an umbrella group under which all existing bar codes fall. There's no guarantee that the world will adopt the EPC, but the proposal already has the support of the Uniform Code Council and EAN International, which are the two main bodies that oversee international bar code standards. Other national and international trade groups and standards bodies are working together. The Auto-ID Center at MIT has been driving towards development of a standard specification for item level tagging in the consumer goods industry called the Electronic Product Code (EPC). This has led to a new group called EPCglobal, a joint venture between the Uniform Code Council (UCC) and EAN International, which maintain the U.P.C./EAN bar code system among others. As stated in the name, a primary goal of EPCglobal is to make the final EPC standard an official global standard. The current thrust of EPCglobal is known as UHF Generation 2 (UHF Gen 2), a Write Once Read Many tag with more memory (96 bits vs. 64 bits) than preceding Class 0 and Class 1 tags. UHF Gen 2 will also provide a bridge to the eventual Class 2 High Memory full Read Write tag. Prior to UHF Gen 2, Class 0 and Class 1 were being utilized for EPC, but they were not interoperable. Consequently, a retailer utilizing an EPC solution such as Wal-Mart would need different RFID readers to read different tags or force all of their suppliers into one technology. UHF Gen 2 will merge the Class 0 and Class 1 standards for a global, interoperable EPC standard. EPC Tag Classes: Currently, several classes of tags fall under the EPCglobal umbrella. The difference between Class 0 and Class 1 is in the data structure and operation. Class 0 tags are read only. Class 1 tags are one-time writeable. The EPC standards call for 5 classes of tags over time. The following table outlines the roadmap for the EPC tag class type: EPC Class Type Features Tag Type Class 0 Read Only Passive (64 bit only) Class 1 Write Once, Read Many (WORM) Passive (96 bit min.) Class 2 (Gen2) Read/ Write Passive (96 bit min.) Class 3 Read/Write with battery power to Semi-Active enhance range Class 4 Read/Write active transmitter Active
The chip manufacturer can only program the Class 0 tag; the Class 1 Version 1 tag can be programmed on the factory floor. While functionally equivalent under the EPCglobal classification system, Class 0 and Class 1 use different hardware technologies to implement the Identity tag functionality. Class 0 tags are programmed when they are manufactured (referred to as Read-Only or R/O ), assuring uniqueness of the tag ID. Class 1 tags can be programmed once, referred to as Write Once, Read Many or WORM, by the user, providing operational flexibility. Class 0 and Class 1 tags also use different protocols, or air interfaces to communicate. So, while both Identity tag implementations perform the required functions, they cannot communicate with each other. Tags of both classes can coexist in an environment, but require readers that speak their language to be identified. EPC code structure The EPC is a number made up of a header and three sets of data. The header identifies the EPC's version number, allowing for different lengths or types of EPC later on. The second part of the number identifies the EPC Manager, most likely the manufacturer of the product. The third, called object class, refers to the exact type of product, most often the Stock Keeping Unit (SKU). The fourth is the serial number unique to the item, which can tell us, for example, exactly to which 330 ml can of Diet Coke we are referring. This makes it possible to quickly find products that might be nearing their expiration date. Example of EPC 01.115A1D7.28A1E6.421CBA30A
The 96 bits contained on the tag are known as the electronic product code (EPC), a unique naming scheme for objects containing the following parts: ISO Standards: The International Organization for Standardization (ISO) is based in Geneva, and its standards carry the weight of law in some countries. All ISO standards are required to be available for use around the world, so users of ISO RFID standards will not have to worry if their systems comply with the different regulations on frequencies and power output for each country where they do business. The ISO is very active in developing RFID standards for supply chain operations and is nearing completion on multiple standards to identify items and different types of logistics containers. ISO Standards for Proximity Cards: ISO 14443 for proximity cards and ISO 15693 for vicinity cards both recommend 13.56 MHz as its carrier frequency. These standards feature a thinner card, higher memory space availability and allow numerous cards in the field to be read almost simultaneously using anti-collision, bit masking and time slot protocols. ISO 14443 proximity cards offer a maximum range of only a few inches. It is primarily utilized for financial transactions such as automatic fare collection, bankcard activity and high security applications. These applications prefer a very limited range for security. ISO 15693 vicinity cards, or Smart Tags, offer a maximum usable range of out to 28 inches from a single antenna or as much as 4 feet using multiple antenna elements and a high performance reader system. ISO Standards for RFID Air interface. The ISO 18000 series is a set of proposed RFID specifications for item management that could be ratified as standards during 2004. The series includes different specifications that cover all popular frequencies, including 135KHz, 13.56 MHz, 860-930 MHz and 2.45 GHz. 18000 1 Part 1 Generic Parameters for Air Interface Communication for Globally Accepted Frequencies 18000 - Part 2: Parameters for Air Interface Communications below 135 KHz o ISO standard for Low Frequency 18000 - Part 3: Parameters for Air Interface Communications at 13.56 MHz o ISO standard for High Frequency o Read \ Write capability 18000 - Part 4: Parameters for Air Interface Communications at 2.45 GHz o ISO standard for Microwave Frequency
o Read \ Write capability 18000 - Part 5: Parameters for Air Interface Communications at 5.8 GHz 18000 - Part 6: Parameters for Air Interface Communications at 860 930 MHz o ISO standard for UHF Frequency o Read \ Write capability o Targeted for same markets as EPC standards. 18000 Part 7: Parameters for Air Interface Communications at 433.92 MHz o Manifest tag for Department of Defense (DOD) Note: In the UHF arena, the EPC standard for air interface is not compatible with the ISO 18000 UHF (Part 6) standard. The ISO 18000 (Part 6) standard only deals with air interface protocols, whereas the EPC standard also includes data structure. The desire is for these two protocols not to be mutually exclusive. ISO Standards for Animal Identification ISO 11748 / 11785: Standard for Animal Identification ISO Supply Chain Standards These are used to identify different types of logistics containers and packaging, in addition to individual items. ISO 17358 - Application Requirements, including Hierarchical Data Mapping ISO 17363 - Freight Containers ISO 17364 - Returnable Transport Items ISO 17365 - Transport Units ISO 17366 - Product Packaging ISO 17367 - Product Tagging (DoD) ISO 10374.2 - RFID Freight Container Identification