URI assigned to a thing by an ISO standard

David Leal

versions 0.3 — 2007-10-15

Foreword

At the meeting of ISO TC184/SC4 in Ibusuki in July 2007, the Industrial Data on the Web ad hoc group proposed a procedure for defining a URI which is assigned to a thing by an ISO standard. Clause 1 of this document describes the proposed procedure.

Clause 2 of this document describes some consequences of the procedure for HTTP GET access over the Web.

NOTE The consequences need to be reviewed with care. It is proposed that the HTTP URIs will be under the domain controlled by the secretariat of the ISO technical committee responsible for the standard. As a consequence, the secretariat of the ISO technical committee will have control of the representation of an HTTP URI.

1 Proposal for a URI assigned to a thing by an ISO standard

1.1 Why define a URI

An ISO standard may assign a URI to a thing so that it can be refered to as a Web resource.

The ISO standard may need to define the URI in accordance with a URI scheme.

NOTE Exceptionally, an ISO standard may assign a URI to a thing, which has already been defined and which is already being used to refer to the thing.

1.2 HTTP URI or URN

A URI can be one of:

NOTE Some people support the use of a URN for a thing defined in an ISO standard, because such a thing cannot be obtained by an HTTP GET and hence an HTTP URI is inappropriate

Some people support the use of a HTTP URI for a thing defined in an ISO standard, because a representation of the thing can be obtained by an HTTP GET, and hence an HTTP URI is useful.

1.3 Person readable or non-person readable URI back end

A URI can be structured with:

A back end can be:

NOTE Some people support the use of a URI back end which is a label in a natural language for a thing defined in an ISO standard, because such a label is memorable.

Some people support the use of a URI back end which is not a label in a natural language for a thing defined in an ISO standard, because the label for a thing in a natural language may be changed whilst the identity of the thing persists.

1.4 Choices of URI

Because of the choices described in clauses 1.2 and 1.3, there are four styles of URI which can be assigned to a thing by an ISO standards.

EXAMPLE An example of each of the choices of URI style for identification of "widget" defined in ISO/TS 12345-6 is as follows:

In this example, the domain http://www.tc123-sc4.org is controlled by the secretariat of ISO TC123/SC4.

An ISO standard may assign more than one URI to a thing. The URIs assigned to a thing may be in different styles.

1.5 Structure of a URI

A URI assigned to a thing by an ISO standard shall either:

1.6 Technical committee defined part of a URI

The technical committee defined part of a URI is all that follows the tech. This can be defined by an ISO standard as required.

For an HTTP URI the technical committee defined part may contain a fragment identifier, separated by a #.

In an equivalent URN, the # is replaced by a :.

EXAMPLE The following HTTP URI contains a fragment identifier:

The equivalent URN is:

NOTE The use of fragment identifiers affects the response of an HTTP GET and the caching on the client side. They can be used if this make the access to the representations of a number of related resources more convenient.

1.7 Specification of the edition of a standard

The edition of a standard shall not be specified in a URI assigned to a thing by an ISO standard.

NOTE 1 The edition is not specified in the URI assigned to a thing by an ISO standard because a subsequent edition of the standard may also assign a URI to the same thing.

NOTE 2 The assignment of a URI to a thing by an ISO standard remains even after the standard has been withdrawn. This is because archived data may use this URI for refer to the thing.

2 Consequences of the proposal for HTTP access

2.1 Response to an HTTP GET

The representation of an HTTP URI can be retrieved by an HTTP GET.

NOTE 1 It is probably not appropriate for an ISO standard to standardise the reepresentation of a URI which is assigned to a thing by an ISO standard. As specified in clause 1.5, the secretariat of the ISO technical committee will control the domain.

A representation may provide information to the user community which is deemed to be useful by the secretariat of the ISO technical committee.

It is not necessary to provide a representation.

The representation may change from time to time

NOTE 2 The representation can contain information about how to purchase the standard which assigns the URI. The representation contain content taken from the international standard, if this has been agreed with ISO Central Secretariat.

2.2 URI resolver

The secretariat of an ISO technical committee may provide a resolver for a URI assigned by an ISO standard as a web service.

EXAMPLE The following URIs are assigned to a thing by ISO/TS 12345-6:

The secretariat for ISO TC123/SC4 provides a resolver for each of these URIs. The resolver is implemented as a REST web service, so that an HTTP GET access can be made to each of:

In each case the representation is exactly the same as that obtained by an HTTP GET access to either of:

NOTE Some people believe that the use of a resolver clarifies that:

Some people think that the use of resolvers is an unnecessary complication.

2.3 Web services provided by the secretariat

A URI resolver is a simple web service. Additional web services may be defined by the secretariat of an ISO technical committee.

NOTE Web services may provide:

EXAMPLE For the object identified by urn:iso:std:iso:ts:12345:-6:tech:things:widget the secretariat may provide the following REST web services:

The RDF/OWL graph of information could specify that "widget" is an owl:Class, and that it is a sub-class of "blabla", as follows:

<?xml version="1.0"?>

<rdf:RDF
   xmlns:rdf  ="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
   xmlns:rdfs ="http://www.w3.org/2000/01/rdf-schema#"
   xmlns:owl  ="http://www.w3.org/2002/07/owl#"
>

 <owl:Class rdf:about="http://www.tc123-sc4.org/ts/12345/-6/tech/things/widget">
  <rdfs:subClassOf rdf:resource="http://www.tc123-sc4.org/ts/12345/-6/tech/things/blabla"/>
 </owl:Class>

<rdf:RDF>

A robust web service would ensure that an HTTP GET would return the same for each of the following HTTP URIs:

Some people regard the first of these URIs as the most useful.

Some people regard the last of these URIs as the most "correct".

2.4 Web services provided by non-ISO organisations

A non-ISO organisation can provide a resolver and other web services for a URI assigned to a thing by an ISO standard.

The web services provded by the non-ISO organisation can be similar to, or even much better than, the web services provided by the secretariat of the technical committee, provided that ISO copyright is respected.

EXAMPLE 1 The Blabla Installers Association has a resolver which gives provides information for its members. Installation guidelines for a widget are provided by an HTTP GET to one of:

EXAMPLE 2 The Wuhan Blabla Company has a resolver which gives provides information for its customers. A description of a widget in Farsi is provided by an HTTP GET to one of: