## Introduction back to ToC

SAREF is a reference ontology for IoT created in close interaction with the industry during a study requested by the European Commission in 2015 and subsequently transferred into an ETSI Technical Specification. SAREF contains core concepts that are common to several IoT domains and, to be able to handle specific data elements for a certain domain, dedicated extensions of SAREF can be created. Each domain can have one or more extensions, depending on the complexity of the domain. As a reference ontology, SAREF serves as the means to connect the extensions in different domains. The document "SmartM2M; Smart Appliances; SAREF extension investigation (ETSI TR 103 411) specifies the rationale and methodology used to create, publish and maintain the SAREF extensions.

This document presents the implementation of the SAREF extension for the smart city domain which based on a limited set of use cases and from available existing data models. This work has been developed in the context of the STF 534 which was established with the goal to create SAREF extensions for the domains of Smart Cities, Smart Industry & Manufacturing, and Smart AgriFood.

### Namespace declarations

Table 1: Namespaces used in the document
s4city | <https://w3id.org/def/saref4city#>
saref | <https://w3id.org/saref#>
xsd | <http://www.w3.org/2001/XMLSchema#>
rdfs | <http://www.w3.org/2000/01/rdf-schema#>
rdf | <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
owl | <http://www.w3.org/2002/07/owl#>
terms | <http://purl.org/dc/terms/>
dc | <http://purl.org/dc/elements/1.1/>