Recommendation ITU-T Y.4484 specifies the framework to support Web of Objects (WoO) ontology based semantic data interoperability of eHealth services in accordance with [ITU-T Y.4452] and [ITU-T Y.4563]. A semantic data interoperability enables the various eHealth systems to combine received information with other information resources and to process it in a manner that preserves meaning. In order to support the semantic data interoperability functions among eHealth systems, this Recommendation applies the WoO framework in [ITU-T Y.4452] and the semantic data interoperability function in [ITU-T Y.4563].