<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
	xmlns:s="http://www.w3.org/TR/WD-rdf-schema#">

<!-- CORE COMMUNICATION

See human readable description at:

http://www-diglib.stanford.edu/diglib/ginf/1999/05/26-core-comm.html

-->

<s:Class rdf:ID="Message">
	<s:comment>The most general message</s:comment>
</s:Class>

<rdf:Property rdf:ID="deliveryInfo">
	<s:comment>An abstract property attached to a message.
		Extend it to provide your own delivery information.</s:comment>
	<s:domain rdf:resource="#Message"/>
</rdf:Property>

<s:Class rdf:ID="ProcessingEntity">
	<s:comment>This resource represents a service, a client etc.,
		in general, some entity able to process communication messages.</s:comment>
</s:Class>

<s:Class rdf:ID="Request">
	<s:subClassOf rdf:resource="#Message"/>
	<s:comment>A request for information</s:comment>
</s:Class>

<rdf:Property rdf:ID="to">
	<s:comment>Identifies the recipient of the message</s:comment>
	<s:subPropertyOf rdf:resource="#deliveryInfo"/>
	<s:domain rdf:resource="#Message"/>
	<s:range rdf:resource="#ProcessingEntity"/>
</rdf:Property>

<rdf:Property rdf:ID="from">
	<s:comment>Identifies the sender of the message</s:comment>
	<s:subPropertyOf rdf:resource="#deliveryInfo"/>
	<s:domain rdf:resource="#Message"/>
	<s:range rdf:resource="#ProcessingEntity"/>
</rdf:Property>

<rdf:Property rdf:ID="inReplyTo">
	<s:comment>Identifies the original request</s:comment>
	<s:subPropertyOf rdf:resource="#deliveryInfo"/>
	<s:domain rdf:resource="#Reply"/>
	<s:range rdf:resource="#Request"/>
</rdf:Property>

<s:Class rdf:ID="Reply">
	<s:subClassOf rdf:resource="#Message"/>
	<s:comment>A reply to an information request</s:comment>
</s:Class>

<s:Class rdf:ID="SuccessfulReply">
	<s:subClassOf rdf:resource="#Reply"/>
	<s:comment>A successful reply to an information request</s:comment>
</s:Class>

<!--s:Class rdf:ID="Warning">
	<s:subClassOf rdf:resource="#Reply"/>
	<s:comment>A warning. A SuccessfulReply may at the same time be an instance of Warning, too</s:comment>
</s:Class-->

<s:Class rdf:ID="Error">
	<s:subClassOf rdf:resource="#Reply"/>
	<s:comment>An error delivered to an information request</s:comment>
</s:Class>

<rdf:Property rdf:ID="errorMessage">
	<s:comment>A human readable error description</s:comment>
	<s:domain rdf:resource="#Error"/>
	<s:range rdf:resource="http://www.w3.org/TR/WD-rdf-schema#Literal"/>
</rdf:Property>

<rdf:Property rdf:ID="warning">
	<s:comment>A warning can be attached to any Message</s:comment>
	<s:domain rdf:resource="#Message"/>
</rdf:Property>

</rdf:RDF>