URN
The "Universal Resource Name" is
currently (March 1993) under development
in the IETF. A requirements specification
is in preparation. It currently looks
as though it will be a short string
suitable for encoding in URI syntax,
for which case the "urn:" prefix
is reserved. The URN shall be encoded
precisely as defined in the (future)
URN standard, except in that:
- If the official description of the
URN syntax includes any constant
wrapper characters, then they shall
not be omitted from the URI encoding
of the URN;
- If the URN has a hierarchical nature,
then the slash delimiter shall be
used in the URI encoding;
- If the URN has a hierarchical nature,
the most significant part shall be
encoded on the left in the URI encoding;
- Any characters with reserved meanings
in the URI syntax shall be escape
encoded
These rules of course apply to any
URI scheme. It is of course possible
that the URN syntax will be chosen
such that the URI encoding will be
a 1-1 transcription.
An example might be a name such as
urn:/iana/dns/ch/cern/cn/techdoc/94/1642-3
but the reader should refer to the
latest URN drafts or specifications.