RFC 1737 (rfc1737) - Page 2 of 7
Functional Requirements for Uniform Resource Names
Alternative Format: Original Text Document
RFC 1737 Requirements for Uniform Resource Names December 1994
become more and more important. This activity of discovering and
utilizing resources can be broken down into those activities where
one of the primary constraints is human utility and facility and
those in which human involvement is small or nonexistent. Human
naming must have such characteristics as being both mnemonic and
short. Humans, in contrast with computers, are good at heuristic
disambiguation and wide variability in structure. In order for
computer and network based systems to support global naming and
access to resources that have perhaps an indeterminate lifetime, the
flexibility and attendant unreliability of human-friendly names
should be translated into a naming infrastructure more appropriate
for the underlying support system. It is this underlying support
system that the Internet Information Infrastructure Architecture
(IIIA) is addressing.
Within the IIIA, several sorts of information about resources are
specified and divided among different sorts of structures, along
functional lines. In order to access information, one must be able
to discover or identify the particular information desired,
determined both how and where it might be used or accessed. The
partitioning of the functionality in this architecture is into
uniform resource names (URN), uniform resource characteristics (URC),
and uniform resource locators (URL). A URN identifies a resource or
unit of information. It may identify, for example, intellectual
content, a particular presentation of intellectual content, or
whatever a name assignment authority determines is a distinctly
namable entity. A URL identifies the location or a container for an
instance of a resource identified by a URN. The resource identified
by a URN may reside in one or more locations at any given time, may
move, or may not be available at all. Of course, not all resources
will move during their lifetimes, and not all resources, although
identifiable and identified by a URN will be instantiated at any
given time. As such a URL is identifying a place where a resource
may reside, or a container, as distinct from the resource itself
identified by the URN. A URC is a set of meta-level information
about a resource. Some examples of such meta-information are: owner,
encoding, access restrictions (perhaps for particular instances),
cost.
With this in mind, we can make the following statement:
o The purpose or function of a URN is to provide a globally unique,
persistent identifier used for recognition, for access to
characteristics of the resource or for access to the resource
itself.
Sollins & Masinter