An Overview of the ISO RFID Data Protocol & Library Applications Paul Chartier Project Editor ISO/IEC 15961 &

1. An Overview of the ISO RFID Data Protocol & Library Applications Paul Chartier Project Editor ISO/IEC 15961 & 15962 June 2006

2. A Basic Question: “Why Standards?” • BSI defines standardisation as the process of “establishing and applying an agreed set of solutions intended for repeated application, directed at benefits for stakeholders and balancing their diverse interests.” • The library community has developed and adopted a broad variety of standards • - but not yet for RFID

3. Some Benefits of RFID Standards • Specifies the rules for components to be fit for purpose • Establishes interoperability of RFID devices • Establishes compatibility between library systems but still supports flexible applications • Avoids systems clash with other applications - given that RFID tags on library items move around the community • Stakes a claim for library systems so that other RFID systems do not corrupt library applications • Provides a better chance of migration as technology improvements are made

4. RFID SystemThe Generic Model RFID Tag Data content Application protocol Air interface APPLICATION

5. RFID StandardsTypes of Standard • Technology - air interface defines what it does • Conformance & Performance compares actual devices with standards • “Middleware” protocols how data and instructions are processed • Data content how business data is supported • Applications making it work for a specific sector

6. ISO RFID StandardsAir Interface Standards Various aspects can be covered, but key are: • The air interface: frequency, modulation, bit encoding • Anticollision • the ability to almost simultaneously address a number of tags unambiguously • not always a requirement • Commands and responses that address memory in terms of blocks (or words, or pages)

7. Tag ArchitectureISO/IEC 18000-3 Mode 1 • Single memory • Can emulate a UII by placing this first • Separate TID and System Info (inc AFI) • Block size & number of blocks can vary

8. An RFID Implementation Based Only on the Air interface

9. Implications of the Application Working at the Air interface Level • Memory map has to be pre-defined for encoding • New data requires a new “message” or memory map rule • Need to understand the memory map to read data • Need to use RFID air interface commands • Data might not be encoded most efficiently • Data might not be encoded most efficiently, especially variable length and optional data

10. APPLICATION PROTOCOL STANDARDS Data Protocol • The Data Protocol addresses data handling between the application and the RF tag • ISO/IEC 15961 Data protocol - application interface: • defines the application commands and responses • uses object identifiers to define all data types • ISO/IEC 15962 Data protocol - data encoding rules • efficient encoding of object identifiers • common data compaction

11. RFID Data ProtocolPositioning ISO/IEC 15961 & 15962

12. RFID Data ProtocolOverview • The Data Protocol fills a gap in communications • Business issues are addressed by the Application Interface • This generates commands and processes responses • The encoding rules convert the data in the commands into efficient encoding on the RF tag

13. RFID Data ProtocolISO/IEC 15961 Application Interface Application Family Data Format Access Method • Generated based on ASN.1 • Abstract syntax • Transfer encoding

14. RFID Data Protocol ISO/IEC 15961 Object Identifiers • Object identifiers used for selective read / write • Based on ISO/IEC 9834-1 established rules and structures • ISO/IEC 9834-1 allows systems to define objects to any level of granularity - just need an object ID • A typical object identifier: 1 0 15961 127 13 • The Hierarchical structure ensures uniqueness of objects • Therefore, possible to encode different data, including closed system objects with no risk of corruption • Extension techniques make the system totally expandable

15. ISO/IEC JTC1/SC31 Logical Tag Structure

16. ISO/IEC Air Interface & Data ProtocolSystem Information • This provides a protocol level - not data - method for managing the interface between application and RF tag, and includes: • Application Family: to enable a subset of RF tags to be in the communication channel • Data Format: to specify the interpretative nature of the encoded bytes on the RF tag • Access Method: to create a logical structure of the bytes encoded on the RF tag

17. ISO/IEC Air Interface & Data ProtocolSystem Information: Application Family • There is a real need to manage the transactions across the air interface • with large population of tags • where there is a risk of different types of tag being present • To be compatible with smart card rules (SC17), RFID for Item Management has to co-manage some codes • Application Family codes are allocated to focus on a meaningful subset within the system, thus excluding RF tags from other systems

18. The AFIA Tool for Efficient Communications

19. The AFI: A Powerful Tool to Select Only Relevant Tags Reader

20. RFID Data ProtocolISO/IEC 15962 Data Encoding Rules Consider this like a bar code encoder, but common to many RF tags Each different air interface has its own Tag Driver, determining precise mapping rules

21. ISO/IEC 15962Data Compaction Schemes • The ISO/IEC 15962 process looks, on a case by case basis of each data object, at the byte encoding on the RF tag • It selects the most efficient encoding scheme from the alternatives (the most efficient scheme is at the top of this list) • Integer: encodes number as binary • Numeric: 4 bits per digit • 5-bit: uppercase alphabetic • 6-bit: uppercase alphabetic, numeric, etc • 7-bit: all ISO 646 (US ASCII) • Octet: unaltered 8-bit • It also preserves user-defined data and supports UTF-8 for international character sets

22. ISO/IEC 15962Logical Memory • A software representation of the RF tag memory • Structured by extracting the system information from the RF tag • Structure • width = block (or codeword) size • length = number of blocks (or codewords)

23. RFID Data ProtocolRevisions to ISO/IEC 15961 & 15962 • 15961-1: 15961 (pub October 2004) needs to be simplified with respect to the data constructs topics New application commands for 18000-6C and sensors • 15961-2: Rules for new Registration Authority for AFIs and other data constructs • 15961-3: Specification of data constructs • 15962: New encoding and data mapping processes for 18000-6C and sensors

24. ISO/IEC 15961Data Constructs • Application Family Identifier (AFI): Used to manage selection across air interface • Data Format: A “shorthand” code to truncate the encoding of long Object Identifiers • Object Identifier for UII - Register of key traceability codes • Object Identifier for other item-attendant data - Register of OID structure for other data

25. Library CommunityData Constructs Process - with SC31 • EDItEUR has made initial request for registration, with the understanding that the application was incomplete • The assignment of data constructs for libraries is accepted • Additional information required for: • Object Identifier for primary code • Object Identifier structure for additional data objects • JTC1/SC31 WG4 has a procedure that can approve the registration and assign the AFI and Data Format • The data constructs will be published and maintained on the web

26. Library CommunityData Constructs - within the Sector • Define data objects (e.g. ISIL, ISBN) • Specify data objects • format (e.g. alphanumeric, numeric, UTF-8) • fixed or variable length • fixed or maximum length • Specify relative-OID value • Extend and revise with no constraints from SC31/WG4

27. Thank you for your attention paul.chartier@praxisconsultants.co.uk