ISO/IEC 24791-5:2012

Information technology — Radio frequency identification (RFID) for item management — Software system infrastructure — Part 5: Device interface

ISO/IEC 24791-5:2012 defines an interface within the Software System Infrastructure (SSI) that provides RFID system control components with low-level access to RFID interrogators for the purpose of optimizing RFID data access and control operations. This interface is designed to be modular with the ability to support multiple RFID air protocols. However, in ISO/IEC 24791-5:2012, the only RFID air protocol supported is Type C of ISO/IEC 18000-6.

Technologies de l'information — Identification de radiofr équence (RFID) pour la gestion d'élément — Infrastructure de systèmes logiciels — Partie 5: Interface de dispositif

General Information

• Status: Published
• Publication Date: 11-Dec-2012
• ICS: 35.040 - Information coding
• ICS: 35.040.50 - Automatic identification and data capture techniques
• Technical Committee: ISO/IEC JTC 1/SC 31 - Automatic identification and data capture techniques
• Drafting Committee: ISO/IEC JTC 1/SC 31/WG 4 - Radio communications
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 16-Oct-2025
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 24791-5:2025 - Information technology — Radio frequency identification for item management software system infrastructure — Part 5: Device interface
• Effective Date: 02-Dec-2023

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 24791-5
First edition
2012-12-15
Information technology — Radio
frequency identification (RFID) for item
management — Software system
infrastructure
Part 5:
Device interface
Technologies de l'information — Identification de radio fréquence
(RFID) pour la gestion d'élément — Infrastructure de systèmes logiciels
Partie 5: Interface de dispositif

Reference number
©
ISO/IEC 2012
©  ISO/IEC 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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Published in Switzerland
ii © ISO/IEC 2012 – All rights reserved

Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Conformance . 1
3  Normative references . 1
4  Terms and definitions . 2
5  Abbreviated terms . 3
6  Software System Infrastructure Architecture Overview . 3
7  UML Modeling . 4
8  Device Interface . 4
8.1  General . 4
8.2  Architecture . 4
9  LLRP Extensions Abstract Definitions . 5
9.1  General . 5
9.2  LLRP Data Types . 6
9.3  ISO15962Read Parameter . 6
9.4  ISO15962ReadResult Parameter . 8
10  LLRP Extensions Binary Encoding . 11
10.1  General . 11
10.2  ISO15962Read Parameter . 11
10.3  ISO15962ReadResult Parameter . 12
Annex A (informative) LLRP Open Source Project References . 14
Annex B (informative) UTF-8 and 8859-1 Conversion Algorithms . 15
Bibliography . 19

© ISO/IEC 2012 – All rights reserved iii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees established
by the respective organization to deal with particular fields of technical activity. ISO and IEC technical
committees collaborate in fields of mutual interest. Other international organizations, governmental and non-
governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology,
ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 24791-5 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 31, Automatic identification and data capture techniques.
ISO/IEC 24791 consists of the following parts, under the general title Information technology — Radio
frequency identification (RFID) for item management — Software system infrastructure:
 Part 1: Architecture
 Part 2: Data management
 Part 3: Device management
 Part 5: Device interface
iv © ISO/IEC 2012 – All rights reserved

Introduction
RFID air interface technology is based on non-contact electro-magnetic communication among interrogators
and tags. RFID software systems are composed of RFID interrogators, intermediate software systems, and
applications that provide control and coordination of air interface operation, tag information exchange, and
health and performance management of system components. RFID technology is expected to increase
effectiveness in many aspects of business by further advancing the capabilities of Automatic Identification and
Data Capture (AIDC). To achieve this goal through the successful adoption of RFID technology into real
business environments, RFID devices, software systems, and business applications shall provide secure and
interoperable services, interfaces, and technologies. This is the goal of the standards defined for RFID
Software System Infrastructure (SSI), ISO/IEC 24791. The composition and operations of SSI exist in systems
that implement other RFID standards including the air interfaces described in the ISO/IEC 18000 series and
the data and interface functions defined in ISO/IEC 15962, ISO/IEC 15963, ISO/IEC 24753 and others.
The goal of this part of ISO/IEC 24791 is to define a device interface that provides RFID controlling software
with low-level access to RFID air interface hardware. This low-level access gives programmers a degree of
control over the sequencing of air protocol commands and direct access to air protocol command parameter.
Using this low-level interface, programmers can optimize RFID data access and control operations.
The interface defined by this part of ISO/IEC 24791 supports the following features:
 efficient, binary transfer syntax over TCP/IP
 access to RFID air protocol commands and command parameters
 support for optimized RFID tag access operations whereby multiple operations can be performed on a
tag with minimal tag state changes
 direct read/write access to all data on an RFID tag
 read one or more individual tag data items (encoded as defined by ISO/IEC 15962) as specified by
their OID using URN notation
 [optional] decode data items (encoded as defined by ISO/IEC 15962) into their Unicode
representation (UTF-8 encoded). Encoding data items is not supported
 support for RFID air protocol type defined by Type C of ISO/IEC 18000-6.
The interface defined in this part of ISO/IEC 24791 provides access to RFID air protocol commands and their
respective command parameters. Therefore using this interface, tag memory banks can be locked, tags can
be killed, and raw-binary RFID tag data can be accessed directly on a tag for both reading and writing. In
addition, individual data items (encoded as defined by ISO/IEC 15962) can be read by specifying each data
item’s OID. Optionally, the interrogator can decode data items read into their character string representation. If
the interrogator cannot decode a data item, then it will return the entire encoded package within which the
data item resides. In this case, it is the responsibility of higher-level software to further decode the data item.
The interface does not support RFID tag data encoding. It is the responsibility of higher-level software (i.e.,
software outside the interface defined by this part of ISO/IEC 24791 to perform data encoding (i.e., binary tag
data representation as defined by ISO/IEC 15962) that is stored on RFID tags.
This part of ISO/IEC 24791 is composed of the EPCglobal™ standard, Low Level Reader Protocol [LLRP], in
its entirety with extensions that support reading RFID tag data items that are encoded according to
ISO/IEC 15962. As does the LLRP standard, this part of ISO/IEC 24791 defines both the abstract functional
capabilities of the interrogator interface and the binary transfer syntax between the interrogator and a
controlling system device. The transfer syntax is defined to be communicated over TCP/IP.
© ISO/IEC 2012 – All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 24791-5:2012(E)

Information technology — Radio frequency identification (RFID)
for item management — Software system infrastructure
Part 5:
Device interface
1 Scope
This part of ISO/IEC 24791 defines an interface within the Software System Infrastructure (SSI) that provides
RFID system control components with low-level access to RFID interrogators for the purpose of optimizing
RFID data access and control operations. This interface is designed to be modular with the ability to support
multiple RFID air protocols. However, in this this part of ISO/IEC 24791, the only RFID air protocol supported
is Type C of ISO/IEC 18000-6.
2 Conformance
Conformance for this part of ISO/IEC 24791 shall satisfy the requirements of the EPCglobal LLRP
specification and the requirements of the LLRP extensions defined in clause 9 of this part of ISO/IEC 24791.
Clause 9 is partitioned into sub-clauses and each sub-clause includes a specific compliance requirement
paragraph. Therefore, conformance to clause 9 of this part of ISO/IEC 24791 is defined by the shall
statements of the compliance requirement paragraphs found within the sub-clauses of clause 9. The
EPCglobal LLRP specification also has specific compliance requirement paragraphs. Therefore, conformance
to the EPCglobal LLRP specification is defined by the shall statements of the compliance requirement
paragraphs found in the LLRP specification.
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 8859-1, Information technology — 8-bit single-byte coded graphic character sets — Part 1: Latin
alphabet No. 1
ISO/IEC 19762-1, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 1: General terms relating to AIDC)
ISO/IEC 19762-3, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 3: Radio frequency identification (RFID)
ISO/IEC 24791-1, Information technology — Radio frequency identification (RFID) for item management —
Software system infrastructure — Part 1: Architecture
EPCglobal™ LLRP, Low Level Reader Protocol
© ISO/IEC 2012 – All rights reserved 1

4 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 19762-1, ISO/IEC 19762-3, and
the following apply.
4.1
device interface
communications interface that provides tag data access and control operations between an RFID Interrogator
and an upstream Client
4.2
endpoint
one of two components that either implements and exposes an interface to other components or uses the
interface of another component
4.3
interrogator endpoint
component that implements and exposes the interrogator interface defined by this part of ISO/IEC 24791 to
other system components
4.4
client endpoint
component that uses the interrogator interface defined by this part of ISO/IEC 24791 to access interrogators
4.5
interface
shared boundary between two functional units, defined by various characteristics pertaining to the functions,
physical or software interconnections, signal exchanges, and other characteristics, as appropriate
4.6
interrogator controller
system component, possibly a distinct physical device, which is capable of exercising the data, control, and
management of interrogators as described in this part of ISO/IEC 24791
4.7
data set
binary representation of a data element’s identifier and its associated data value that is encoded according to
the rules defined by ISO/IEC 15962 standard access method
4.8
data item
pairing of a data element’s identifier and its associated data value that is encoded according to the rules
defined by ISO/IEC 15962, regardless of access method
4.9
encoded package
self-describing binary data from an RFID tag memory bank that, when given the memory bank’s DFSID (which
defines the ISO/IEC 15962 access method and data format), decoding software can fully decode the
individual data item(s) to extract the encapsulated data
4.10
protocol data unit
unit of information communicated between network peers
2 © ISO/IEC 2012 – All rights reserved

5 Abbreviated terms
For the purposes of this part of ISO/IEC 24791, the symbols and abbreviated terms given in ISO/IEC 19762-1,
ISO/IEC 19762-3, and the following apply.
AIDC
Automatic Identification and Data Capture
DSFID
Data Storage Format Identifier
LLRP
Low Level Reader Protocol
RF
Radio Frequency
SSI
Software System Infrastructure
UML
Unified Modeling Language
6 Software System Infrastructure Architecture Overview
ISO/IEC 24791-1 defines the architecture for the Software System Infrastructure. The basic relationship
among the interfaces and implementations of the Software System Infrastructure is depicted in Figure 1 —
Architecture Overview including Relationships to other RFID Standards.

Figure 1 — Architecture Overview including Relationships to other RFID Standards
© ISO/IEC 2012 – All rights reserved 3

The Data Interface, Device Interface, and Device Management each provide one or more interfaces that allow
a client to communicate with a service-providing implementation, either within the same computing device or
across a network. These client and service implementations are consistently referred to as Client Endpoints
and Services Endpoints, respectively, and in general, the Client Endpoint accesses the capabilities provided
by the Services Endpoint. It is the responsibility of the specific standard to define the formats, procedures,
operations, and conformance requirements of each interface.
7 UML Modeling
Although Figure 1 provides a general overview of the relationship between the interfaces and implementations
in the SSI, Unified Modeling Language (UML) is used in the remainder of the document to graphically
represent the organization and operation of the Device Interface and implementations so that a precise and
common understanding of the relationships among the components can be defined.
UML is a very rich language, but for simplicity only the Physical Diagram subset of the language is used to
represent the architecture of the Software System Infrastructure. Physical diagrams, comprised of Component
Diagrams and Deployment Diagrams, represent the relationships among the functions and the interfaces
provided by the SSI architectural elements as well as how these functions might exist in standards compliant
solutions, respectively. Refer to ISO/IEC 24791-1 for a more complete description how UML is used in this
part of ISO/IEC 24791.
8 Device Interface
8.1 General
This clause describes the device interface defined by this part of ISO/IEC 24791 in terms of the overall
software system infrastructure described in ISO/IEC 24791-1. Annex A of this part of ISO/IEC 24791 provides
further references to several open sources projects that offer software libraries and utilities supporting this
device interface.
8.2 Architecture
As defined in ISO/IEC 24791-1, the Device Interface defines data and control operation between the Device
Interface Services Endpoint on an RFID interrogator and the Client Endpoint typically on a different physical
device. A Device Interface component exposes an interface as represented in Figure 2 — Device Interface
Representation whereby a Device Interface Services Endpoint provides services to a Device Interface Client
Endpoint over an interface binding as specified in clause 10 of this part of ISO/IEC 24791, ISO/IEC 24791-5.
The Client and Services Endpoints may exist in a single device or may be accessed across a network.
24791-5
Device Interface
Services Endpoint
Figure 2 — Device Interface Representation
4 © ISO/IEC 2012 – All rights reserved

The Device Interface is responsible for supporting and exercising the capabilities provided by the RFID air
protocols to achieve the tag and sensor access goals of an RFID software system. In order to achieve this
goal, the standards provided for the data, control, and management functions at this level in the Software
System Infrastructure are air-protocol aware and capable of fully exercising specific features of the supported
air protocol standards. Equivalently, it is not a goal to provide a single, abstract interrogator interface that
provides a common interface regardless of the specific air protocol in use. Doing so would reduce the ability of
the software systems to access the specific features provided by existing and future air protocols.
The Device Interface supports requests for, and communication of, tag information between the Services
Endpoint on RFID interrogators and the Client Endpoint on upstream devices. The data functions include
capabilities such as reading, writing, filtering, and the reporting of tag and sensor data. Synchronous, event-
based, and externally triggered operation may be supported for access requests.
The control functions in the architecture provide an interface for the Device Interface Client to exercise specific
control over the access operations on an interrogator. This control is specific to each air protocol and is
intended to provide the necessary capabilities to allow for software system, interrogator, and RF environment
optimization. The control function of the Device Interface also supports the delivery of system, interrogator, tag,
and RF environment data from the Services Endpoint to the Client Endpoint. This data can be used by
implementations to provide the control required to achieve the desired system goals.
9 LLRP Extensions Abstract Definitions
9.1 General
ISO/IEC 24791-5 directly references and therefore utilizes the complete structure, definitions, formats, and
procedures of the EPCglobal Low Level Reader Protocol (LLRP) specification [LLRP] with the addition of
extensions that provide support for reading and decoding RFID Type C of ISO/IEC 18000-6 tag data formatted
and operated upon according to ISO/IEC 15962. If an implementation of this part of ISO/IEC 24791 is unable
to decode a tag data object, then it shall transfer to the client endpoint the raw, binary contents of the entire
data set (i.e., the data object and its associated header data such as precursor and length fields).
Tag data may be encoded according to ISO/IEC 15962 to represent different character sets (e.g., the default
ISO/IEC 8859-1, or UTF-8, or application defined). Tag data encoded as UTF-8 (compaction code 111) is
fully compatible with this part of ISO/IEC 24791, and is transferred “as-is”. It is the responsibility of the client
application to convert this UTF-8 data to other character sets if needed. Tag data found to be encoded as
application defined (compaction code 000) cannot be decoded by an implementation of this part of
ISO/IEC 24791 and as such, it shall be transferred as raw, binary data. Tag data that is encoded with no
directory, directory, or tag data profile access methods and with the following compaction codes (001, 010,
011, 100, and 101) when decoded have the same single byte value on the tag and in UTF-8 format. If the
compaction scheme is declared as Octet encoded (compaction code 110) then the encoding on the tag shall
need to be converted to UTF-8 if any byte value is in the range between 80 to FF . An example of the
h h
conversion algorithm is given in Appendix B.
The remainder of this part of ISO/IEC 24791 defines the ISO/IEC 24791-5 extensions to LLRP. This clause
provides an abstract definition of interface parameters used to request and return decoded tag data. Clause
10 defines the transfer syntax details required to implement these interface parameters.
When referencing the EPCglobal LLRP specification, it will be helpful to understand that there are several
EPCglobal terms that are synonymous with ISO/IEC terms. The following list enumerates EPCglobal terms
with definitions using ISO/IEC terminology:
 EPC (Electronic Product Code)
identifier corresponding to the ISO/IEC unique item identifier (UII) as defined by air protocol interface Type
C of ISO/IEC 18000-6 when memory bank 01 bit 17 is zero
2 h
 EPC Memory Bank
equivalent to the UII memory bank as defined by air protocol interface Type C of ISO/IEC 18000-6
© ISO/IEC 2012 – All rights reserved 5

 Class 1, Gen 2 (C1G2)
equivalent to the air protocol interface, Type C, as defined in ISO/IEC 18000-6
 Reader
equivalent to an interrogator as defined in ISO/IEC 19762-3
The ISO/IEC 15962 RFID tag data encoding rules are defined in terms of data items that represent a pairing
of the data item identifier (OID) and its associated data value. Data items, as defined by ISO/IEC 15962 rules,
include data encoded as either packed objects or concatenated data sets (i.e., two different access methods
defined by ISO/IEC 15962).
This part of ISO/IEC 24791 extends LLRP for the purpose of providing a Client endpoint with the following
specific capabilities:
a) request an Interrogator to search a tag for one or more specific OIDs and to report back to the Client the
occurrences of each OID as it is found on the tag;
b) request an Interrogator to report all OIDs found on a tag;
c) request an Interrogator to check for duplicate occurrences of one or more OIDs on a tag and return the
number of instances found;
d) request for either raw or decoded data to be returned for each OID returned in the response to a
particular request.
The following sub-sections provide abstract definitions of LLRP extensions designed to satisfy these
capabilities. Clause 10 provides the binary transfer syntax definition for these extensions.
The LLRP extensions defined in this part of ISO/IEC 24791 correspond to the section titled Access Operation
of the LLRP specification which defines air-protocol-specific access-operation parameters (e.g., Read, Write,
Kill, Lock, etc.). These extensions define a new LLRP access-operation parameter and four new supporting
parameters. The following sub-sections define these new LLRP parameters as they apply to Type C of
ISO/IEC 18000-6.
9.2 LLRP Data Types
LLRP includes definitions of abstract data field types. For this part of ISO/IEC 24791, these data field types
are extended with one additional field type:
ObjectIdentifier – This field type is used to represent Object Identifiers (OID) as defined by ISO/IEC 15961-1.
An Object Identifier is as a character string that is structured following the URN syntax rules defined by
RFC 3061.
9.3 ISO15962Read Parameter
9.3.1 General
This parameter, ISO15962Read, is an extension to LLRP. It is an access-operation parameter that supports
reading one or more ISO/IEC 15962 data items from a specified memory bank on an RFID tag. The results of
this access operation are reported with an associated ISO15962ReadResult parameter (see 9.4).
This access operation requires that the Interrogator is capable of parsing data encoded on the tag only
enough to locate one or more encoded data items given a list of one or more object identifiers (OIDs).
Although the Client may request decoded data from the Interrogator, the Interrogator is not required to support
the ability to decode tag data and it may return the raw binary-encoded data as it is read directly from the tag.
In this case, it is the responsibility of the Client software to decode this binary data. If the Interrogator does
return raw binary dat
...