ITU‐T's Technical Reports and Specifications 671 Figure 16 – Technical workflow of matching resources up with the toponym database in the integrated management for smart sustainable cities 3.4 Interface specifications for management service There are three service technical interface specifications for management service, namely model service interface specification, data service interface specification, and event service interface specification. Only the aspects of the model service interface specification are described in detail: background, scope, and content. 3.4.1 Model service interface specification 3.4.1.1 Background In IMSSC, all departmental applications, such as urban construction, water conservancy, electric power, environmental protection, transportation, and fire‐fighting, need to be combined with concrete models. Nevertheless, research is limited to some application fields, and systems must be modified or even re‐developed when new problems appear. It will take more time and money to restrict the models' application in IMSSC [b‐Nativi]. The model service interface specification proposed in this Technical Report offers a general and unified service interface, and with the storage and invoke for the models separated from the users, the sharing, management as well as interoperability for heterogeneous models or model chains can be implemented.