# Towards Crowdsourcing Internet of Things (Crowd-IoT): Architectures, Security and Applications
###### Abstract  
Crowdsourcing can play an important role in the Internet of Things (IoT) applications for information sensing and gathering where the participants are equipped with geolocated devices. Mobile crowdsourcing can be seen as a new paradigm contributing to the development of the IoT. They can be merged to form a new and essential platform in crowdsourcing IoT paradigm for data collection from different sources and communication mediums. This paper presents a comprehensive survey for this new Crowdsourcing IoT paradigm from four different perspectives: (1) Architectures for Crowd-IoT; (2) Trustworthy, Privacy and Security for Crowd-IoT; (3) Resources, Sharing, Storage and Energy Considerations for Crowd-IoT; and (4) Applications for Crowd-IoT. This survey paper aims to increase awareness and encourage continuing developments and innovations from the research community and industry towards the Crowdsourcing IoT paradigm. crowdsourcing Internet of Thing (IoT); crowdsourcing IoT; mobile sensing; social sensing; collaborative sensing +
Footnote †: journal: _Future Internet_  
gives a survey on crowdsourcing for disaster applications). However, there is currently no comprehensive survey or review paper on crowdsourcing IoT and edge crowdsourcing to our best knowledge. This paper aims to fill the gap in this survey area and give valuable insights into the research area. This paper first discusses the background knowledge on the traditional and mobile crowdsourcing paradigm and highlights representative crowdsourcing platforms. Next, the paper focuses on IoT and reviews the existing crowdsourcing architecture literature related to IoT, including crowdsourcing for the Social IoT. The centralized architectures and layered structures for crowdsourcing IoT are discussed. A new crowdsourcing Internet of Things (Crowd-IoT) architecture is proposed. The proposed architecture has seven layers. These layers are Identification Layer, Crowd Object Layer, Communication/Network Layer, Middleware Layer, Crowd Computation Layer, Application/User Layer, Security, Privacy, and Trust Layer. The Crowd-IoT preserves the advantages from the advancement of IoT and mobile technologies while offering specific processing and computation of the crowd data. In centralized architectures, the server interacts with participants after receiving the tasks from requesters. For a large number of connected users and multiple interactions, the large volume of sensing data creates significant computational overheads f1 or the conventional crowdsourcing platform. Furthermore, conventional crowdsourcing techniques cannot meet the requirements for time-sensitive IoT tasks due to unforeseen delays and variations in response time. An approach termed edge computing attempts to use the current and surrounding infrastructures, components, or devices for information processing and return it to the cloud. Edge and Fog computing approaches provide an alternative to improving conventional crowdsourcing platforms. Edge and Fog are emerging technologies for IoT applications that can meet the requirements for computational, storage, and distributed access amongst the users and the Internet. On the one hand, many edge or fog nodes, e.g., base stations, routers, and so on, are flexible to be deployed close to users in IoT. On the other hand, the sensed or collected data can be utilized by adversaries to perform hostile attacks and inferences. Despite the importance of crowdsourcing, the privacy issue is an issue for large-scale deployment of crowdsourcing applications. One of the reasons is that task requestors or owners and users may fully trust the crowdsourcing server. For the participants, the tasks and sensing data may contain private information such as point of interest, location, and so on. On the other hand, the task requestors may inadvertently reveal private information such as their daily routine when they release the tasks. Thus, it is essential to keep the sensing tasks unknown to the server.