Working towards the next version of the SWIM Supporting Material
Working towards the next version of the SWIM Supporting Material
Guidance
IETF RFC 3986 is available at https://tools.ietf.org/html/rfc3986. It details the generic syntax for uniform resource identifiers (URIs). The standard gives the following examples of URI schemes:
- ftp://ftp.is.co.za/rfc/rfc1808.txt
- http://www.ietf.org/rfc/rfc2396.txt
- ldap://[2001:db8::7]/c=GB?objectClass?one
- mailto:[email protected]
- news:comp.infosystems.www.servers.unix
- tel:+1-816-555-1212
- telnet://192.0.2.16:80/
- urn:oasis:names:specification:docbook:dtd:xml:4.1.2
The ATM Information Reference Model uses the urn scheme.
The specification accepts that not all information definitions adopt the IETF RFC 3986 approach. Therefore it permits other ways to ensure a concept is uniquely identifiable. This means the requirement can be satisfied by ensuring the concept can be identified by being unique within its namespace. In effect the identifier becomes the namespace plus the concept name.
Verification Support
Completeness
Check that either:
- Each concept has a unique identifiers in accordance with IETF RFC 3986.
or
- Each concept can be uniquely identified through some other mechanism e.g. by being uniquely named in a namespace.
Examples
The example below shows how an identifier can be embedded into an XML schema. It makes use of the "id" attribute within the XML schema definition language.
A complete example is available at: complete example.
<xs:element name="status" id="abcd"/>