This specification defines UUIDs (Universally Unique IDentifiers) --
also known as GUIDs (Globally Unique IDentifiers) -- and a Uniform
Resource Name namespace for UUIDs. A UUID is 128 bits long and is intended to
guarantee uniqueness across space and time. UUIDs were originally used
in the Apollo Network Computing System (NCS), later in the Open Software
Foundation's (OSF's) Distributed Computing Environment (DCE), and then
in Microsoft Windows platforms.
This specification is derived from the OSF DCE specification with the
kind permission of the OSF (now known as "The Open Group"). Information
from earlier versions of the OSF DCE specification have been incorporated
into this document. This document obsoletes RFC 4122.