4. Proposed architecture

software flexibility and for these reasons, an IoT platform in a Smart City environment should

1. Device agnosticism: The changes in the configuration of a device should be limited to updating the driver and at maximum the data format when adding or updating a devices, allowing hardware developers to develop their new generations of products without being

2. Device manageability: An inherent characteristic of a Smart Cities deployment is that the devices and sensors are placed at large distances in a Smart City environment, the IoT

3. Usage of open APIs: The devices and sensors present in a Smart City context inherently generate large amounts of data. It can happen that a conspicuous amount of this data remains not analyzed due to its unavailability to other users than the ones originally intended. The IoT platforms should therefore allow the access to shareable data, becoming

The data in the IoT world comes mainly from things but can also arrive in the form of metadata from users. IoT and Smart Cities are more than a sink for incoming data, data intelligence being the key concept. This implies relatively strict requirements in terms of data [13, 14]:

1. Data processing and analytics services: An IoT platform's usefulness is given by its ability to

2. Data scalability: Especially in a Smart City environment the amount of IoT data has the tendency to grow fast, for example when monitoring environmental data. The IoT platform should therefore have the necessary features in order to manage the data using

In the last decade, Travel Recommendation Systems (TRSs) have benefited from the Information Communication Technology (ICT), which has become the main source of information for the tourists, assisting them in choosing services around them [16]. As the technology makes its way into the fabric of everyday life, it become easier even for people with disabilities to take

In particular, the IoT, as an enabler technology, can offer people with disabilities the assistance and support they need to achieve a good quality of life and allows them to participate in the social and economic life. In [17], the authors propose an IoT architecture to assist people with disabilities and envision some application scenarios where such users can benefit from the IoT, such as during shopping, at school or in a domestic environment. They claim how the IoT can

platform has to include methods for the remote management of devices.

like this a true motor for future innovative applications.

process the collected data and turn it to usable information.

archiviation and culling methods, preferably fully automated.

3. Overview on the use of IoT technologies for accessible tourism

comply with following flexibility rules [15]:

34 Assistive Technologies in Smart Cities

2.3. Data requirements

advantage of TRSs.

limited by legacy or compatibility issues.

As mentioned in Section 1, in this work we introduce an IoT platform suitable for a Smart City environment and applied to the sustainable management of the tourist flow in the city of Cagliari, Sardinia's capital, which is one of the two biggest island in Italy and one of the most attractive point for tourism, especially in summer. In such a scenario, we envision that, through the use of virtualization technologies, each object in the real world is associated to its virtual counterpart in the cloud. This is a common practice in the latest IoT research efforts [24], since the virtualization of the physical devices enhances their capabilities, making the objects capable to: (i) describe their characteristics with semantic technologies in order to be able to interact with other virtual objects; (ii) identify, analyze and manage the context of the object's surroundings, taking the decision accordingly; (iii) facilitate the search and discovery of devices and services, continuously joining, moving across and leaving the network.

This approach has manifold motivations: (i) it enables objects to speak the same language at the virtual level; (ii) it enhances the service search and discovery; (iii) it decouples the service requests and the actual IoT objects which satisfy the request and (iv) it offers personalized

Using IoT for Accessible Tourism in Smart Cities http://dx.doi.org/10.5772/intechopen.77057 37

In the following paragraphs, we describe in detail the layers proposed for the architecture.

(1) Application layer: This is where user applications are deployed. Each application is composed of two interfaces: a front-end interface, which represent the access point for users or objects to interact with the system, and a back-end interface, which connects this layer to the rest of the platform and enables the application to be fulfilled by the lower layer.

(2) Service layer: At this level, service requests are analyzed and augmented with a range of facts concerning the human user, including user context, the type of disability, his/her

The Service Request Analysis (SRA) receives the query from the Application layer and interact with the User Characterization block to obtain information regarding the user and the context

In particular, the User Characterization (UC) includes all the knowledge the system has accumulated regarding each user interacting with the system and his/her preferences. This block has then the ability to complement the query with additional information so that each application is truly personalized based on the user. This is an important component in our platform because many applications in a Smart City scenario, such as the one for sustainable tourism, are characterized by personal choices: requests coming from different users can have different solutions. This is particularly true for the use case of disabled persons, posing new constraints

To have a broader view of the user, the UC block alone is not enough. This is due to the fact that the UC only accumulate static information, and does not take into account the specific situation the user is involved in. This is the role of the Context Awareness block, which considers the context in which the query has been made. For example, a tourist with a certain disability looking for a museum to visit, can receive different recommendations based on the accessibility of the structure, the time of day, the possible routes to reach it, the presence of uphills and downhills, the

Finally, since an application is composed of one or more services, there is the need of a Decomposer, which collect the information obtained by the other blocks in this layer and decide which atomic tasks (sensing, actuation, computational) are needed to fulfill the query. Then, it

(3) Virtualization Layer: This layer is responsible for virtualizing the sensor (& actuation) data for any service needs, which is stored in a related database. Objects and devices of the real world are represented digitally in this level in the form of Virtual Objects (VOs) and their

To overcome the limited capabilities of the IoT objects, in the virtual world the VOs enhance their capabilities and enable them to perform additional operations. White canes, i.e. canes for

distance from other museums or the number of people in the queue waiting to visit it.

profile, the preferences in terms of PoI categories and security policies.

in the SRA that have to be taken into account when solving the query.

forward a group of subqueries for the Virtualization Layer.

offered services are described in terms of semantics.

experience to users based on their own needs and traits.

in which the query has been made.

#### 4.1. Proposed architecture

The proposed platform relies on the Cloud IoT architecture [25], named Lysis, organized on four distinct levels (Figure 1). Service discovery and information exchange do not need objects to be in vicinity of each other, since they take place in the virtual world through the exploit of social relations.

In the following the four levels as described in details: the highest level is the Application Layer in which user-oriented applications are deployed; the Service Layer is responsible to receive the application requests and map them to the atomic services available in the lower layer; this layer is the Virtualization Layer, which interfaces directly with the real world and enhances objects' functionalities; the last level is the Real World Layer, containing the real physical devices of the Smart City. Two additional cross-layers are needed to manage the quality requirements of the applications and to ensure that every communication takes place in a trustworthy and secure way, according to the previously listed requirements.

Figure 1. Cloud-based IoT architectural solution.

This approach has manifold motivations: (i) it enables objects to speak the same language at the virtual level; (ii) it enhances the service search and discovery; (iii) it decouples the service requests and the actual IoT objects which satisfy the request and (iv) it offers personalized experience to users based on their own needs and traits.

In the following paragraphs, we describe in detail the layers proposed for the architecture.

virtual counterpart in the cloud. This is a common practice in the latest IoT research efforts [24], since the virtualization of the physical devices enhances their capabilities, making the objects capable to: (i) describe their characteristics with semantic technologies in order to be able to interact with other virtual objects; (ii) identify, analyze and manage the context of the object's surroundings, taking the decision accordingly; (iii) facilitate the search and discovery

The proposed platform relies on the Cloud IoT architecture [25], named Lysis, organized on four distinct levels (Figure 1). Service discovery and information exchange do not need objects to be in vicinity of each other, since they take place in the virtual world through the exploit of

In the following the four levels as described in details: the highest level is the Application Layer in which user-oriented applications are deployed; the Service Layer is responsible to receive the application requests and map them to the atomic services available in the lower layer; this layer is the Virtualization Layer, which interfaces directly with the real world and enhances objects' functionalities; the last level is the Real World Layer, containing the real physical devices of the Smart City. Two additional cross-layers are needed to manage the quality requirements of the applications and to ensure that every communication takes place in a trustworthy and secure

of devices and services, continuously joining, moving across and leaving the network.

4.1. Proposed architecture

36 Assistive Technologies in Smart Cities

way, according to the previously listed requirements.

Figure 1. Cloud-based IoT architectural solution.

social relations.


The Service Request Analysis (SRA) receives the query from the Application layer and interact with the User Characterization block to obtain information regarding the user and the context in which the query has been made.

In particular, the User Characterization (UC) includes all the knowledge the system has accumulated regarding each user interacting with the system and his/her preferences. This block has then the ability to complement the query with additional information so that each application is truly personalized based on the user. This is an important component in our platform because many applications in a Smart City scenario, such as the one for sustainable tourism, are characterized by personal choices: requests coming from different users can have different solutions. This is particularly true for the use case of disabled persons, posing new constraints in the SRA that have to be taken into account when solving the query.

To have a broader view of the user, the UC block alone is not enough. This is due to the fact that the UC only accumulate static information, and does not take into account the specific situation the user is involved in. This is the role of the Context Awareness block, which considers the context in which the query has been made. For example, a tourist with a certain disability looking for a museum to visit, can receive different recommendations based on the accessibility of the structure, the time of day, the possible routes to reach it, the presence of uphills and downhills, the distance from other museums or the number of people in the queue waiting to visit it.

Finally, since an application is composed of one or more services, there is the need of a Decomposer, which collect the information obtained by the other blocks in this layer and decide which atomic tasks (sensing, actuation, computational) are needed to fulfill the query. Then, it forward a group of subqueries for the Virtualization Layer.

(3) Virtualization Layer: This layer is responsible for virtualizing the sensor (& actuation) data for any service needs, which is stored in a related database. Objects and devices of the real world are represented digitally in this level in the form of Virtual Objects (VOs) and their offered services are described in terms of semantics.

To overcome the limited capabilities of the IoT objects, in the virtual world the VOs enhance their capabilities and enable them to perform additional operations. White canes, i.e. canes for blind or visually impaired people, wheelchair but also museums, parks or busses can communicate among them without any problem at this level even if they all use different communication technologies: simple technologies, such as RFID tags and NFC, can be attached to Points of Interest (PoIs) to enhance the visiting experience of tourists by interpreting information about the environment and making choices accordingly, for example by pushing additional information regarding the PoI to users [26].

the adoption of virtual counterparts, in order to monitor the overall level of the applications, both from a communication point of view (Quality of Service) and from a user point

Using IoT for Accessible Tourism in Smart Cities http://dx.doi.org/10.5772/intechopen.77057 39

This section presents an accessible solution designed on top of the IoT platform presented in the previous section, aiming to provide useful information to tourists in general, with particular attention to the ones with special needs. The application has been developed for the cruise ship tourists who land in the city of Cagliari, but it could be applied to many Western European tourist destinations, regardless of the means of arrival (i.e. plane, train, or ship).

When arriving in Cagliari, many cruise ship tourists, often prefer to take a walking tour rather than taking an organized tour. After getting off the cruise ship, these people have to spend too much time to get the needed information about programming their visit. And time is a very critical aspect for cruise ship tourists, due to the limited number of hours the cruise ship usually stays at the call port. This aspect gets worse for disabled people, depending on the type and degree of disability. In the case of mobility disability, for instance, a destination like Cagliari, where reaching the most important attractions require a lot of walking uphill, due to the natural and geographical features of the city, many tourists are constrained to limit their visit to the areas around the port. Instead, with some detailed information about accessible routes in the city, more tourists could reach all the attractions of interest within walking distance of the port getting a better experience from their visit. This is why we designed and developed a mobile application dedicated to generic tourists and specifically adapted to accessible tourism. In case of physical impairments, this mobile application is capable to optimize visits to specific mobility user needs. In this work we adopt the paradigm of people

In the recent years, tourism experiences of people with disabilities have largely been a research key topic [27]. Research results have been focused on accessible tourism and accommodation preferences [5]. Most of the available tools are based on web sites for travel planning with focus on inclusive tourism such as Tur4All (https://www.tur4all.com/) and Jaccede.com (https://www.jaccede.com/). Specific tools face just single aspects of the problem. LinkedQR [28] is a tool to improve the collaboration between QR codes and Linked Data, through mobile and Web technologies. Nevertheless, the role of IoT in tourism is expected to create innovative

There is a lack of tools specifically designed for everyone and able to perform specific outcomes for disabled. Our application addresses this challenge, following the paradigm of whole-of-life to tourism, considering that 30% of a population will have access requirements

of view (Quality of Experience), a quality manager is still needed.

inclusion and universal access to information and tourism assets.

5. Proposed accessible tourism solution

5.1. Cruise tourism

experiences for consumers [29].

at some stage during their life [4].

To activate a new VO, the system has to find a match between the possible VO templates and the information (metadata) provided by the physical device; such information comprehends: objects' characteristics; objects' location; resources, services, and quality parameters provided by objects. When a match is found, a new instance of the object is created (i.e. the web server representing the VO itself), which run in the Virtual Object Execution Space (VOES), where all the instances of VOs run.

Each VO has two interfaces: the first one enables the VO to create a standardized communication procedure with the physical object; this way, the VO can communicate with the object using a set of different protocols based on the situation at hand. The other interface allows the VO to "speak" with all the other VOs in the VOES; thank to this, it is possible even for physical objects with have different communication technologies to communicate among them and become interoperable at the virtual level.

The VO registry stores a semantic description for each active VOs in the VOES, in the form of metadata, which is then used every time there is the need to search for a particular VO.

This metadata is particularly useful in the case of accessible tourism, where the information regarding the different objects available for people with disability needs to be described with the correct metadata in order to be easily discoverable; this is the case for example of busses with a platform for tourists in a wheelchair or of museums which provide audio guides for visually impaired tourists.

When the Search and Discovery Engine is activated by the upper layers, it search in the VO registry to find any potential available VO that can match the query, i.e. any VO whose metadata can match the services required.


the adoption of virtual counterparts, in order to monitor the overall level of the applications, both from a communication point of view (Quality of Service) and from a user point of view (Quality of Experience), a quality manager is still needed.
