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is there any available hierarchical URN scheme that can use URLs or domain names as "prefixes"?

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Stasik
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  • A URN is always going to start with urn: and is not going to be hierarchical. It might be better if you could explain in more detail what you are really asking for and why - how would you use such a URN scheme? When you say prefix do you mean something other than the "urn:" at the start? What would it be like to use a URL as a "prefix"? – barefootliam Apr 05 '16 at 03:47
  • @barefootliam, why can not i have something like urn:stackoverflow.com:question:36411988 to give an id to this question, without saying how to reach it (stackoverflow.com domain name is used to ensure uniqueness) – Stasik Apr 05 '16 at 06:24

2 Answers2

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All URN Namespace Identifiers (NID) are registered here: http://www.iana.org/assignments/urn-namespaces

As it wouldn’t be feasible to create a URN NID for every domain name, it would probably be a single NID with the domain name in the Namespace Specific String (NSS). For example, urn:example:com:stackoverflow:…, urn:example:org:wikipedia:….

The problem with this approach is that domain name ownership and/or the content accessible from the corresponding URLs can change over time, but URNs should always refer to the same entity.

There doesn’t seem to be a URN NID for this purpose.

You didn’t describe your use case, but maybe the tag URI scheme can help. It solves the problem of changing domain ownership and of changing content, but only the domain owner (whether previous owners or the current one) may mint new tag URIs. For example, Stack Overflow might generate the following Tag URI for your question:

tag:stackoverflow.com,2015:36411988
Community
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unor
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Yes, there is a URN namespace that uses domain names as a prefix, since 2005!

It is the FDC URN Namespace, which is of the following form:

urn:fdc:<domain_name>:<date>:<id>

Examples given in the spec:

urn:fdc:example.com:2002:A572007
urn:fdc:example.net:200406:ivr:51089
urn:fdc:example.org:20010527:img089322-038
Jean Hominal
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