Following a standards-based numbering system and proper RAIN tag encoding processes, ensures that every item is uniquely identifiable.
RAIN RFID supports two fundamental numbering systems – one specified by GS1 and the other specified by ISO. Within RAIN tag encodings, these numbering systems are differentiated based on the value of the T-bit (ISO/IEC 18000-63 numbering system identifier Toggle bit). The T-bit is a singular bit located in the PC Word portion of Memory Bank 01. Setting the T-bit to 0₂ denotes that the GS1 numbering system is in use; setting the T-bit to 1₂ denotes that the ISO numbering system is in use.
Each numbering system further comprises a set of encoding schemes. GS1 specifies EPC (Electronic Product Code) schemes (see GS1 TDS), whereas ISO specifies UIIs (Unique Item Identifiers) using AFIs (Application Family Identifiers), DIs (Data Identifiers), and DSFIDs (Data Storage Format Identifiers) as registered in the Data Constructs Register.
There are several ISO encoding schemes (UII) dedicated for RAIN technology. These are listed and registered here:
- General landing page: AIM Global Registration Authority
- Registration Authority ISO/IEC 15961: Data Constructs Register
The RAIN Alliance-managed ISO encodings schemes are:
- RAIN Alliance-Issued CIN with Free-Form Encoding Schemes (BINARY and TEXT) – Version 2025-12-15
- RAIN URI Identifier – Version 2025-12-15
- RAIN Free-Form Encoding Schemes (BINARY and TEXT) – Version 2025-12-15
ISO encoding schemes (AFI & DSFID) best practices
The RAIN industry shipped more than 52.8 billion RAIN tag chips/ICs globally in 2024. With the expectation that the industry will connect trillions of items in the coming years, the RAIN Alliance provides an extended set of RAIN tag encoding options to:
- ensure a complete set of encoding schemes for all RAIN enabled applications;
- ensure open, globally unique identification;
- ensure non-interference between RAIN applications;
- provide interoperability between barcodes and RAIN RFID; and
- establish a clear migration path for non-compliant encodings to become compliant.
Adopting the registered RAIN encodings schemes and the RAIN Alliance best practices ensures that organisations can reliably identify, locate, and authenticate the items of interest across diverse applications and environments.
Who needs standards-based numbering systems?
Everyone and every system which uses RAIN technology.
Why do we need standards-based numbering systems?
RAIN tags must each have unique and properly encoded identification numbers so that individual items can be identified, located, and authenticated. If RAIN tag data is not uniquely and properly formatted during the encoding process, unwanted items may be read. This is known as tag noise.
For example:
- Without unique numbers: A postal service tracks the packages traveling through its facility by tagging each box. If a box of apparel arrives with items that are tagged with a numbering system similar to that of the postal service, then there is potential for duplicate numbers to appear for each item.
- Without proper encoding: A marathon clocks runners’ times at the finish line using tagged race bibs. If a delivery truck full of tagged items is parked near the finish line, and those tags are not correctly encoded using a standards-based numbering system, then the marathon may not be able to read all of the runner’s tags before they move past the finish line due to interference with tags in the delivery truck.
Following a standards-based numbering system ensures unique and proper RAIN tag encoding, which in turn enables effective and efficient filtering of your and others’ tags. This means that you read only your tags of interest, ensuring the success of both your and others’ deployments.
How can I drive encoding best practices?
The RAIN Alliance is calling on its members and partners to commit to using encoding best practices for the success of all RAIN deployments.
- Use a RAIN Alliance-issued Company Identification Number (CIN): Apply Here.
- Educate yourself and your partners in proper tag encoding: RAIN Alliance members can learn about the existing standards-based numbering systems and share this knowledge with your partners. For example, a RAIN Alliance member commits to publicizing encoding resources to their partner network; or a tag converters’ operations team participates in a RAIN Alliance-hosted webinar; or a standards organization includes additional, intuitive information about encoding.
- Make sure your reader reports tags read correctly: Please see the RAIN Alliance Reader Interface Guide (RCI)