Hi Jean, I have completed the exercise of translating to XML the example in the document (compose.pdf). There is one XML that describes the mixins specific for the provider (example.xml), and the xml document that describes the entities that implement the example in the document (occi-monitoring-example.xml). They are uploaded in the "monitoring" branch. I have left your comments in the occi-monitoring-example.xml complaining about the fact that mixin attributes "melt" into the resource in a completely opaque way. On my side, I add that it is also impossible to characterize an attribute with any sort of semantic (in my case, input, control, metric). About the occi.xsd document: -) line 113: amyURI instead of anyURI -) the attribute type <xs:complexType name="attributeType"> <xs:sequence> <xs:element name="value" type="xs:anyURI" minOccurs="0" maxOccurs="unbounded"> </xs:element> </xs:sequence> <xs:attribute name="name" type="xs:string"></xs:attribute> <xs:attribute name="value" type="xs:string"></xs:attribute> </xs:complexType> The two attributes are ok (name+value) but the unbounded sequence of URIs puzzles me: what is its meaning exactly. And, overall, this is not the "attribute" as defined in the core model, upper right corner of fig. 2: this is represented as the "attributeSpecType", right? Is there a relationship between the two? I guess no. Also: I have not found an easy way to test the example: do you have an inexpensive suggestion for me? Bye! Augusto PS: ah, is there interest regarding XMPP? -- Augusto Ciuffoletti Dipartimento di Informatica Università di Pisa 56100 - Pisa (Italy)