The URN “urn:iso:std:iso:19719:ed-1:v1:en,fr” denotes the first version of the first edition of ISO 19719, which is published bilingually in English and French.

For the instance property, the most practical way I’ve found of implementing this is to define a URN that encapsulates additional information regarding the error. Here is an example URN for reference. urn:companyname:api:error:protocol:badRequest:f29f57d7-e1f8-4643-b226-fa18f15e9b71

urn:x-pdf:a08d875ad57045edf70d283087a0e339 (PDF fingerprint)

This document describes a Uniform Resource Name (URN) Namespace Identification (NID) convention as prescribed by the Internet Engineering Task Force (IETF) for identifying, naming, assigning, and managing persistent resources in the legal domain.

A URI identifies a resource either by location, or a name, or both. A URI has two specializations known as URL and URN. A Uniform Resource Locator (URL) is a subset of the Uniform Resource Identifier (URI) that specifies where an identified resource is available and the mechanism for retrieving it.URL defines how the resource can be obtained. It does not have to be HTTP URL (http://), a URL can also be (ftp://) or (smb://) A Uniform Resource Name (URN) is a Uniform Resource Identifier (URI) that uses the URN scheme, and does not imply availability of the identified resource. Both URNs (names) and URLs (locators) are URIs, and a particular URI may be both a name and a locator at the same time.