About Tag Data Translation

EPC Tag Data Translation v1.0 provides a machine-readable framework for representing the formats and encoding/decoding rules for the Electronic Product Code (EPC) identifiers, that are defined normatively in EPCglobal Tag Data Standards
The EPC is a flexible and extensible framework for assigning unique identifiers to objects, assets and locations. It already supports GS1 identifiers that are widely used in many industry sectors, especially in logistics, retail and FMCG. The EPC also supports a general-purpose general identifier (GID) and identifiers for suppliers to the US Department of Defense.

In the EPC Network architecture, EPC identifiers are usually represented as pure-identity Uniform Resource Identifiers (URI) strings when they are included within messages that are exchanged between organizations, such as in the queries and responses to EPC Information Services.

For encoding in low-cost radio-frequency identification (RFID) tags, a more compact binary encoding is used, in which the EPC identifier is represented in as little as 64 or 96 bits of information.
The EPCglobal Tag Data Standard also defines a tag-encoding URI that contains the same information as the binary encoding, but in a more readable format - and including the detail about the length (in bits) of the EPC identifier within the RFID tag and the 'fast filter' value that is also encoded in the tag for most EPC identifier schemes.
It also defines how existing identifiers (in particular the GS1 identifiers) can be encoded as an Electronic Product Code (EPC).

Tag Data Translation provides a way to future-proof the EPC Network by making it easy for hardware and software to handle new EPC identifier schemes, as they are introduced.
This is achieved through the use of TDT definition files, represented in XML, which can be used to validate that an EPC is correctly formatted, or to encode/decode it into one of its other representations, as required. Click here for an example of a TDT definition file.
The structure and interpretation of the TDT definition files is explained in the Tag Data Translation standard.

Dr Mark Harrison (Cambridge Auto-ID Lab) served as co-chair of the EPCglobal Tag Data Translation work group during 2004-2006 and was a major contributor to the EPCglobal Tag Data Translation 1.0 standard

Together with his former colleague, Dr James Brusey, he has also written some Tag Data Translation software in Java and contributed this to the Fosstrak open source software project for track and trace using the EPC Network standards

TDT v1.0 was ratified on 21st January 2006 and supported the EPC identifiers that were defined at that time in TDS v1.1 r1.27.

An updated version of TDT (v1.4) is currently under preparation within the EPCglobal community. This will provide some additional clarifications, support for GS1 Application Identifiers - and include updated TDT definition files for all EPC identifiers defined in TDS v1.4

You can download our Tag Data Translation software from the Fosstrack open source project.

Please contact mark.harrison@cantab.net for further details