# Smart City for Sustainable Development: Applied Processes from SUMP to MaaS at European Level
## 4 The European Smart City Applied Process at the Sectorial Level
### The MaaS Levels  
The MaaS paradigm may be a better solution for facing urban mobility challenges. The paradigm is enabled by emerging ICT, which allow transport operators to design, manage and realize mobility services tailored on specific travel user needs [44] using advanced energy vehicles. The ICT support operators manage information flows for historical configurations in real time. However, as with other smart solutions, MaaS requires a new state among theories, rules and implementations. In the following, transport system theories are focused on in relation to implications deriving from emerging ICT. By selecting the applications in transport systems at the urban level, the emerging ICT actually used in the city are as follows ([13; 37; 45]):  
* Internet of Things (IoT) for exchanging of data between objects;
* Big data (BD) for managing large amounts of data in real time, in terms of volumes, variety and velocity;
* Blockchain (BC) for managing transactions in value or sensitive data between decision makers;
* Artificial intelligence (AI) for making decisions between sets of alternatives. It is necessary to also recall digital twin, which can be used for virtual representation of a real-world physical system. The recalled emerging ICT are used in some transport sectors but without a systematic approach for implementing the MaaS paradigm. For making the MaaS solutions effective, it is essential to improve and enhance knowledge of the mobility phenomenon. Some authors study travelers' attitudes towards MaaS [46], but urban complexity requires improvement on theories about the transport system and their components: the supply subsystem, including transport infrastructures and services [4]; the demand subsystem, including people and business mobility needs and their travel choices [17]; and demand-supply interactions, for reproducing how people and business mobility needs are satisfied by infrastructures and services [16]. Classical Transport System Models (TSM) can be enhanced by integrating them with emerging ICT and specific energy cycles. To evolve MaaS, it is necessary to define theoretical advances that explicitly insert the emerging ICT in the TSM. ICT and TSM became parts of Decision Support Systems (DSS), which support public authorities, companies for transport system design and management. DSS enable a priori and a posteriori quantitative evaluations of sustainability goals and their achievements measured by distances from targets [13]. Recently, in the literature [16], different levels of advancements for the MaaS paradigm have been introduced (Figure 8):  
* N-MaaS (No MaaS), comprising single and separate transport systems without integration;
* MaaS 1.0 or I-MaaS, comprising a transport system with services integrated by means of an ICT platform used by operators and users (ICT MaaS); in this level, different sublevels can be identified in relation to the typology of provided services (e.g., information or financial transactions);
* MaaS 2.0 or T-MaaS, comprising I-MaaS systems enhanced by TSM that support transport system designing and management inside a DSS platform; with emerging ICT and theoretical advancements of classical TSM, it is possible to better understand the mobility phenomena;
* MaaS 3.0 or S-MaaS (Sustainable, TSM and ICT MaaS), comprising I-MaaS systems and T-MaaS enhanced transport system design and management, considering the sustainability goals and targets, recalled in the Introduction Section, by means of Space Economic Transport Interaction (SETI) models and Environmental Impact Functions (EIFs). Emerging ICT (artificial intelligence, big data, internet of things, block chain, digital twin, etc.) work for the development of DSS together with T  
Figure 8: Advancements of the MaaS paradigm. decision makers to individuate system configurations based on the mobility needs pursued by the SDGs. Different theoretical issues, regarding single components and their interactions within a unique MaaS platform remain open.