NEPOMUK Message Ontology
extends the NEPOMUK Information Element framework into the domain of
messages. Kinds of messages covered by NMO include Emails and instant
messages. This document gives an overview of NMO and describes its
classes and properties.
This document arose from
the work of the Task-Force ontologies within the NEPOMUK project.
This document is a DRAFT made available by the Nepomuk Consortium for
discussion only. This document is a work in progress and may be
updated, replaced, or rendered obsolete by other documents at any time.
This document is a part
in a set of seven documents, which together comprise the complete
specification of the Nepomuk Information Element Ontology Framework.
These are: NIE,
NFO,
NCO,
NMO,
NCAL,
NEXIF,
NID3.
Introduction
Messages - the domain of
the Nepomuk Message Ontology (NMO) form a large part of
the body of data available on a desktop. The user sends them, receives
them, forwards them to other users, stores them and recalls them when
they are needed. They are almost never self contained, always refering
to something - to events, people, organizations, projects, activities,
anything the user might be interested in. The purpose of NMO is to
bring messages to the world of ontologies so that these links can be
made explicit.
The Concept of a Message
The concept of a message in everyday english is broad. The
Thesaurus.com website
lists 'message' under 36 different meanings. NMO had to limit itself to
a familiar domain of electronic communication. In NMO a message is a
finite sequence of bytes containing arbitrary information exchanged
between a sender and at least one receiver. Notice the difference
between definitions of a Message and a File - the presence of at least
one sender and receiver, and the absence of the requirement about
durability. Of course it doesn't exclude the possibility of a file
interpreted as a message (e.g. a .eml file).
Even with these limitations, a taxonomy of messages can be defined.
Subconcepts may include an Email, a message sent with an instant
messaging application, an SMS, a voice message, a forum private message
etc.
A message can have multiple receivers. It can be sent to multiple
Contacts. A mailing list is treated as one contact, since the message
itself is sent to one email address. The fact that it is forwarded to
other people is not expressed in the byte sequence that comprises the
message and therefore falls beyond the scope of NIE. Blog posts and
forum posts are not considered Messages in the NMO sense. This
statement may seem arbitrary at first. In the case of a forum post, the
actual Message according to the NMO definition (and the overall notion
of nie:DataObject) is the HTTP packet generated by the browser and
received by the Web Server. It is usually hardly relevant for a typical
user. There are other ontologies, better suited towards description of
blogs and forums, most notably SIOC.
Description of a Message
The most important information about each Message is the sender,
receiver and the dates. NMO provides properties to express this
information. The choice of those properties has been inspired by header
fields found in emails, but they are definitely applicable to other
kinds of messages too. The nmo:references property
(\ref{nmo:references}) can be used to express relations in dialogues.
It would link an answer with the message it refers to.
